essay on development can be a threat to nature

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Destruction of nature is as big a threat to humanity as climate change.

By Michael Le Page

Farming and housing occupies large amounts of land globally

Steve Proehl/Getty

We are destroying nature at an unprecedented rate, threatening the survival of a million species – and our own future, too. But it’s not too late to save them and us, says a major new report.

“The evidence is incontestable. Our destruction of biodiversity and ecosystem services has reached levels that threaten our well-being at least as much as human-induced climate change.”

With these words chair Robert Watson launched a meeting in Paris to agree the final text of a major UN report on the state of nature around the world – the biggest and most thorough assessment to date, put together by 150 scientists from 50 countries.

The report, released today, is mostly grim reading. We humans have already significantly altered three-quarters of all land and two-thirds of the oceans. More than a third of land and three-quarters of freshwater resources are devoted to crops or livestock.

Around 700 vertebrates have gone extinct in the past few centuries. Forty per cent of amphibians and a third of coral species, sharks and marine mammals look set to follow.

Less room for wildlife

Preventing this is vital to save ourselves, the report says. “Ecosystems, species, wild populations, local varieties and breeds of domesticated plants and animals are shrinking, deteriorating or vanishing,” says one of the the report’s authors, Josef Settele. “This loss is a direct result of human activity and constitutes a direct threat to human well-being in all regions of the world.”

The main reason is simple. Our expanding farms and cities are leaving less room for wildlife. The other major causes are the direct exploitation of wildlife such as hunting, climate change, pollution and the spread of invasive species. Climate change is set to become ever more destructive.

Read more: Is life on Earth really at risk? The truth about the extinction crisis

But we can still turn things around, the report says. “Nature can be conserved, restored and used sustainably while simultaneously meeting other global societal goals through urgent and concerted efforts fostering transformative change,” it states.

It also says that where land is owned or managed by indigenous peoples and local communities, there has been less destruction and sometimes none at all.

The aim of the report, by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), is to provide an authoritative scientific basis for international action . The hope is that it will lead to the same pressure for action as the latest scientific report by the Intergovernmental Panel on Climate Change (IPCC), on limiting warming to 1.5°C.

“Good knowledge is absolutely essential for good governance,” says Watson, who chaired the IPCC from 1997 to 2002 . “I’m optimistic that this will make a difference.”

Bioenergy threat

But the challenge is immense. All countries except the US have ratified the 1992 UN Convention of Biodiversity and are supposed to be conserving biodiversity and promoting its sustainable use.

Despite this, more than 80 per cent of the agreed international targets for 2020 will not be met, says the report. In fact, as of 2016, half the signatory countries hadn’t yet drawn up plans on how to meet the targets .

The problem isn’t just our focus on economic growth regardless of the impact on the natural world. Current plans for reducing carbon dioxide emissions to net-zero to limit climate change rely heavily on bioenergy, which requires a lot of land. This will accelerate species loss as well as threatening food and water security, says the report.

Read more: Rewilding: Can we really restore ravaged nature to a pristine state?

In fact, the bioenergy push is already causing harm. For instance, rainforests are being cut down in Indonesia and Malaysia to grow palm oil to make biodiesel for cars in Europe .

Transforming our civilisation to make it more sustainable will require more connected thinking, the report says. “There’s a very fragmented approach,” says Watson. “We’ve got to think about all these things in a much more holistic way.”

For instance, there are ways of tackling climate change that will help biodiversity too, such as persuading people to eat less meat and planting more trees. But the devil is in the detail – artificial plantations would benefit wildlife far less than restoring natural forests.

Some of the solutions set out in the report may not be welcome to all. In particular, it effectively calls for wealthy people to consume less, suggesting that changing the habits of the affluent may be central to sustainable development worldwide.

Read more: Half the planet should be set aside for wildlife – to save ourselves

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Humans Are Speeding Extinction and Altering the Natural World at an ‘Unprecedented’ Pace

By Brad Plumer

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WASHINGTON — Humans are transforming Earth’s natural landscapes so dramatically that as many as one million plant and animal species are now at risk of extinction, posing a dire threat to ecosystems that people all over the world depend on for their survival, a sweeping new United Nations assessment has concluded.

The 1,500-page report, compiled by hundreds of international experts and based on thousands of scientific studies, is the most exhaustive look yet at the decline in biodiversity across the globe and the dangers that creates for human civilization. A summary of its findings , which was approved by representatives from the United States and 131 other countries, was released Monday in Paris. The full report is set to be published this year.

Its conclusions are stark. In most major land habitats, from the savannas of Africa to the rain forests of South America, the average abundance of native plant and animal life has fallen by 20 percent or more, mainly over the past century. With the human population passing 7 billion, activities like farming, logging, poaching, fishing and mining are altering the natural world at a rate “unprecedented in human history.”

At the same time, a new threat has emerged: Global warming has become a major driver of wildlife decline , the assessment found, by shifting or shrinking the local climates that many mammals, birds , insects, fish and plants evolved to survive in. When combined with the other ways humans are damaging the environment, climate change is now pushing a growing number of species, such as the Bengal tiger , closer to extinction.

As a result, biodiversity loss is projected to accelerate through 2050, particularly in the tropics, unless countries drastically step up their conservation efforts.

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Facts about the nature crisis

What you need to know about the nature crisis

We are experiencing a dangerous decline in nature and humans are causing it:

• We are using the equivalent of 1.6 Earths to maintain our current way of life and ecosystems cannot keep up with our demands. (Becoming Generation Restoration, UNEP)
• One million of the world’s estimated 8 million species of plants and animals are threatened with extinction. (IPBES)
• 75 percent of the Earth’s land surface has been significantly altered by human actions, including 85 percent of wetland areas. (IPBES)
• 66 percent of ocean area is impacted by human activities, including from fisheries and pollution. (IPBES)
• Close to 90% of the world’s marine fish stocks are fully exploited, overexploited or depleted. (UNCTAD)
• Our global food system is the primary driver of biodiversity loss with agriculture alone being the identified threat 24,000 of the 28,000 species at risk of extinction. (Chatham House and UNEP)
• Agricultural expansion is said to account for 70% of the projected loss of terrestrial biodiversity. (CBD)

From 7-19 December 2022, countries met in Montreal for  COP15  to strike a landmark agreement to guide global actions on biodiversity.  The Kunming-Montreal Global Biodiversity Framework lays out an ambitious plan that addresses the key drivers of biodiversity loss and puts us on the path to halt and reverse nature loss by 2030. See  UNEP’s COP-15 page  for more information and the latest updates.

What are the impacts of nature loss and degradation

Nature loss has far-reaching consequences. Damaged ecosystems exacerbate climate change, undermine food security and put people and communities at risk. 

• Around 3.2 billion people, or 40 percent of the global population, are adversely affected by land degradation.
• Up to $577 billion in annual global crop production is at risk from pollinator loss.
• 25 percent of global greenhouse gas emissions are generated by land clearing, crop production and fertilization.
• Development is putting animals and humans in closer contact increasing the risk of diseases like COVID-19 to spread. About 60 percent of human infections are estimated to have an animal origin. 
• 100-300 million people are at increased risk of floods and hurricanes because of coastal habitat loss. 
• Declines in nature and biodiversity at current trajectories will undermine progress toward 35 out of 44 of the targets of SDGs related to poverty, hunger, health, water cities, climate, oceans and land.

What do we need to do to halt and reverse nature loss?

We only have until the end of the decade to bend the curve on nature and biodiversity loss. Transformational change is possible if we start now at every level from local to global. Actions that should be taken include:

• The UN Biodiversity Conference (COP 15) in Montreal later this year must culminate in a clearly defined, ambitious Post-2020 Global Biodiversity Framework that is matched by finances and accountability mechanisms to achieve the framework’s targets. Read more about COP 15 .
• Investments in nature-based solutions will need to at least triple by 2030 if the world is to meet its climate change, biodiversity and land degradation targets. Explore UNEP’s State of Finance for Nature report and watch the video.
• Preventing the large-scale collapse of nature will require effective conservation of more of our land, inland waters and oceans, as well as the world delivering on its current commitment to restore at least one billion hectares of degraded land in the next decade. Learn about the UN Decade on Ecosystem Restoration.
• Agriculture has altered the face of the planet more than any other human activity. We need to transform our food systems to become more sustainable and resilient in order to reverse environmental degradation, restore ecosystems and ensure food and nutritional security. Read about food system impacts on nature and biodiversity.
• Governments must assign a financial value on the services that nature provides to people so that environmental action can be prioritized in policy and investment decisions. Read the IPBES new report for how assigning values to nature can help address biodiversity loss.
• Tax structures and subsidies should be reformed to incentivize sustainable production and ensure that environmental degradation no longer pays. This joint FAO-UNDP-UNEP report calls for governments to rethink the way agriculture is subsidized and supported.
• Corporations should put sustainability at the heart of decision making and focus on new sustainable business models to meet society’s needs in ways less impactful on the environment. UNEP’s Global Environment Outlook for Business briefs provide roadmaps that business can follow to address our environmental challenges.
• All financial players should align their business strategies with global and national sustainability goals including the SDGs, the Paris Agreement and the upcoming Biodiversity Framework. Read more about how to catalyze action across the financial system .

Related Sustainable Development Goals

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Climate change: a threat to human wellbeing and health of the planet. taking action now can secure our future.

BERLIN, Feb 28 – Human-induced climate change is causing dangerous and widespread disruption in nature and affecting the lives of billions of people around the world, despite efforts to reduce the risks. People and ecosystems least able to cope are being hardest hit, said scientists in the latest Intergovernmental Panel on Climate Change (IPCC) report, released today.

“This report is a dire warning about the consequences of inaction,” said Hoesung Lee, Chair of the IPCC. “It shows that climate change is a grave and mounting threat to our wellbeing and a healthy planet. Our actions today will shape how people adapt and nature responds to increasing climate risks.”

The world faces unavoidable multiple climate hazards over the next two decades with global warming of 1.5°C (2.7°F). Even temporarily exceeding this warming level will result in additional severe impacts, some of which will be irreversible. Risks for society will increase, including to infrastructure and low-lying coastal settlements.

The Summary for Policymakers of the IPCC Working Group II report,  Climate Change 2022: Impacts, Adaptation and Vulnerability was approved on Sunday, February 27 2022, by 195 member governments of the IPCC, through a virtual approval session that was held over two weeks starting on February 14.

Urgent action required to deal with increasing risks

Increased heatwaves, droughts and floods are already exceeding plants’ and animals’ tolerance thresholds, driving mass mortalities in species such as trees and corals. These weather extremes are occurring simultaneously, causing cascading impacts that are increasingly difficult to manage. They have exposed millions of people to acute food and water insecurity, especially in Africa, Asia, Central and South America, on Small Islands and in the Arctic.

To avoid mounting loss of life, biodiversity and infrastructure, ambitious, accelerated action is required to adapt to climate change, at the same time as making rapid, deep cuts in greenhouse gas emissions. So far, progress on adaptation is uneven and there are increasing gaps between action taken and what is needed to deal with the increasing risks, the new report finds. These gaps are largest among lower-income populations. 

The Working Group II report is the second instalment of the IPCC’s Sixth Assessment Report (AR6), which will be completed this year.

“This report recognizes the interdependence of climate, biodiversity and people and integrates natural, social and economic sciences more strongly than earlier IPCC assessments,” said Hoesung Lee. “It emphasizes the urgency of immediate and more ambitious action to address climate risks. Half measures are no longer an option.”

Safeguarding and strengthening nature is key to securing a liveable future

There are options to adapt to a changing climate. This report provides new insights into nature’s potential not only to reduce climate risks but also to improve people’s lives.

“Healthy ecosystems are more resilient to climate change and provide life-critical services such as food and clean water”, said IPCC Working Group II Co-Chair Hans-Otto Pörtner. “By restoring degraded ecosystems and effectively and equitably conserving 30 to 50 per cent of Earth’s land, freshwater and ocean habitats, society can benefit from nature’s capacity to absorb and store carbon, and we can accelerate progress towards sustainable development, but adequate finance and political support are essential.”

Scientists point out that climate change interacts with global trends such as unsustainable use of natural resources, growing urbanization, social inequalities, losses and damages from extreme events and a pandemic, jeopardizing future development.

“Our assessment clearly shows that tackling all these different challenges involves everyone – governments, the private sector, civil society – working together to prioritize risk reduction, as well as equity and justice, in decision-making and investment,” said IPCC Working Group II Co-Chair Debra Roberts.

“In this way, different interests, values and world views can be reconciled. By bringing together scientific and technological know-how as well as Indigenous and local knowledge, solutions will be more effective. Failure to achieve climate resilient and sustainable development will result in a sub-optimal future for people and nature.”

Cities: Hotspots of impacts and risks, but also a crucial part of the solution

This report provides a detailed assessment of climate change impacts, risks and adaptation in cities, where more than half the world’s population lives. People’s health, lives and livelihoods, as well as property and critical infrastructure, including energy and transportation systems, are being increasingly adversely affected by hazards from heatwaves, storms, drought and flooding as well as slow-onset changes, including sea level rise.

“Together, growing urbanization and climate change create complex risks, especially for those cities that already experience poorly planned urban growth, high levels of poverty and unemployment, and a lack of basic services,” Debra Roberts said.

“But cities also provide opportunities for climate action – green buildings, reliable supplies of clean water and renewable energy, and sustainable transport systems that connect urban and rural areas can all lead to a more inclusive, fairer society.”

There is increasing evidence of adaptation that has caused unintended consequences, for example destroying nature, putting peoples’ lives at risk or increasing greenhouse gas emissions. This can be avoided by involving everyone in planning, attention to equity and justice, and drawing on Indigenous and local knowledge.

A narrowing window for action

Climate change is a global challenge that requires local solutions and that’s why the Working Group II contribution to the IPCC’s Sixth Assessment Report (AR6) provides extensive regional information to enable Climate Resilient Development.

The report clearly states Climate Resilient Development is already challenging at current warming levels. It will become more limited if global warming exceeds 1.5°C (2.7°F). In some regions it will be impossible if global warming exceeds 2°C (3.6°F). This key finding underlines the urgency for climate action, focusing on equity and justice. Adequate funding, technology transfer, political commitment and partnership lead to more effective climate change adaptation and emissions reductions.

“The scientific evidence is unequivocal: climate change is a threat to human wellbeing and the health of the planet. Any further delay in concerted global action will miss a brief and rapidly closing window to secure a liveable future,” said Hans-Otto Pörtner.

For more information, please contact:

IPCC Press Office, Email: [email protected]   IPCC Working Group II:  Sina Löschke,  Komila Nabiyeva: [email protected]

Notes for Editors

Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change

The Working Group II report examines the impacts of climate change on nature and people around the globe. It explores future impacts at different levels of warming and the resulting risks and offers options to strengthen nature’s and society’s resilience to ongoing climate change, to fight hunger, poverty, and inequality and keep Earth a place worth living on – for current as well as for future generations. 

Working Group II introduces several new components in its latest report: One is a special section on climate change impacts, risks and options to act for cities and settlements by the sea, tropical forests, mountains, biodiversity hotspots, dryland and deserts, the Mediterranean as well as the polar regions. Another is an atlas that will present data and findings on observed and projected climate change impacts and risks from global to regional scales, thus offering even more insights for decision makers.

The Summary for Policymakers of the Working Group II contribution to the Sixth Assessment Report (AR6) as well as additional materials and information are available at https://www.ipcc.ch/report/ar6/wg2/

Note : Originally scheduled for release in September 2021, the report was delayed for several months by the COVID-19 pandemic, as work in the scientific community including the IPCC shifted online. This is the second time that the IPCC has conducted a virtual approval session for one of its reports.

AR6 Working Group II in numbers

270 authors from 67 countries

• 47 – coordinating authors
• 184 – lead authors
• 39 – review editors
• 675 – contributing authors

Over 34,000 cited references

A total of 62,418 expert and government review comments

(First Order Draft 16,348; Second Order Draft 40,293; Final Government Distribution: 5,777)

More information about the Sixth Assessment Report can be found  here .

Additional media resources

Assets available after the embargo is lifted on Media Essentials website .

Press conference recording, collection of sound bites from WGII authors, link to presentation slides, B-roll of approval session, link to launch Trello board including press release and video trailer in UN languages, a social media pack.

The website includes  outreach materials  such as videos about the IPCC and video recordings from  outreach events  conducted as webinars or live-streamed events.

Most videos published by the IPCC can be found on our  YouTube  channel. Credit for artwork

About the IPCC

The Intergovernmental Panel on Climate Change (IPCC) is the UN body for assessing the science related to climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 to provide political leaders with periodic scientific assessments concerning climate change, its implications and risks, as well as to put forward adaptation and mitigation strategies. In the same year the UN General Assembly endorsed the action by the WMO and UNEP in jointly establishing the IPCC. It has 195 member states.

Thousands of people from all over the world contribute to the work of the IPCC. For the assessment reports, IPCC scientists volunteer their time to assess the thousands of scientific papers published each year to provide a comprehensive summary of what is known about the drivers of climate change, its impacts and future risks, and how adaptation and mitigation can reduce those risks.

The IPCC has three working groups:  Working Group I , dealing with the physical science basis of climate change;  Working Group II , dealing with impacts, adaptation and vulnerability; and  Working Group III , dealing with the mitigation of climate change. It also has a  Task Force on National Greenhouse Gas Inventories  that develops methodologies for measuring emissions and removals. As part of the IPCC, a Task Group on Data Support for Climate Change Assessments (TG-Data) provides guidance to the Data Distribution Centre (DDC) on curation, traceability, stability, availability and transparency of data and scenarios related to the reports of the IPCC.

IPCC assessments provide governments, at all levels, with scientific information that they can use to develop climate policies. IPCC assessments are a key input into the international negotiations to tackle climate change. IPCC reports are drafted and reviewed in several stages, thus guaranteeing objectivity and transparency. An IPCC assessment report consists of the contributions of the three working groups and a Synthesis Report. The Synthesis Report integrates the findings of the three working group reports and of any special reports prepared in that assessment cycle.

About the Sixth Assessment Cycle

At its 41st Session in February 2015, the IPCC decided to produce a Sixth Assessment Report (AR6). At its 42nd Session in October 2015 it elected a new Bureau that would oversee the work on this report and the Special Reports to be produced in the assessment cycle.

Global Warming of 1.5°C , an IPCC special report on the impacts of global warming of 1.5 degrees Celsius above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty  was launched in October 2018.

Climate Change and Land , an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems  was launched in August 2019, and the  Special Report on the Ocean and Cryosphere in a Changing Climate  was released in September 2019.

In May 2019 the IPCC released the  2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories , an update to the methodology used by governments to estimate their greenhouse gas emissions and removals.

In August 2021 the IPCC released the Working Group I contribution to the AR6, Climate Change 2021, the Physical Science Basis

The Working Group III contribution to the AR6 is scheduled for early April 2022.

The Synthesis Report of the Sixth Assessment Report will be completed in the second half of 2022.

For more information go to  www.ipcc.ch

Related Content

Remarks by the ipcc chair during the press conference to present the working group ii contribution to the sixth assessment report.

Monday, 28 February 2022 Distinguished representatives of the media, WMO Secretary-General Petteri, UNEP Executive Director Andersen, We have just heard …

February 2022

Fifty-fifth session of the ipcc (ipcc-55) and twelfth session of working group ii (wgii-12), february 14, 2022, working group report, ar6 climate change 2022: impacts, adaptation and vulnerability.

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What are the threats to nature?

There’s no mystery about why nature is under threat. The assault on the natural world comes from all directions but especially from harmful human activity. 

For thousands of years much of human civilisation and advancement has come at the expense of other species and our environment.   

Not everyone has been responsible. Many cultures have always lived in step with nature. Many have understood that their lives today and tomorrow are entwined with having vibrant, abundant nature .

But in the main, humans have found clever ways to lay waste to the Earth and to push countless species to the edge of existence.

But we can use our supreme brain power and, if needed, self-interest. There is enough evidence of nature’s decline  – and our knowledge of how we could put things right is becoming ever more sophisticated.

It is time to put human ingenuity to use in truly cleverer ways.

Habitat loss: getting out of the habit

For nature to thrive, not just survive, we now need to transform how land is used. This includes how we farm, how we live in cities, our use and re-use of energy and materials and how we tackle poverty without undermining nature.

First, let’s get the C-word out of the way. We can’t entirely predict how things will play out, but climate change is already affecting nature in the UK and globally – see our nature and climate article for more.

Apart from climate change, the main threat to nature starts with habitat loss. This is the number one threat to the diversity of species and to the healthy functioning of the natural systems we rely on for water, food, materials and more of the things we often take for granted. These natural systems are often referred to as eco-systems.

Habitat loss is not an activity in itself. You won’t see a company HQ or a warehousing somewhere with a ‘Habitat Loss “‘R” Us’ neon sign. But habitat is being lost all of the time because it has become implicit in how our economy, stock markets and businesses work and profit from a long list of daily activities we have grown used to as normal. For instance: 

• How we farm land for food and others crops in intensive industrial ways is affecting wildlife and the quality of soils and water.
• The way we clear forests for timber, to grow palm oil and to make way for farming and cattle ranching.
• Mining for minerals and for fossil fuels is fundamentally dirty and destructive on land and, increasingly, at sea.
• Construction of leisure resorts, roads and dams all too often harms nature and turns beauty spots into tourist hotspots or industrial zones which then bring pollution and over-use of water.

Destroying nature for profit

It is unlikely that you will see any of this damage reflected in the price of goods in the shops. It is also rare for any of these true costs to appear in company annual reports or the FTSE or Dow Jones indices.

But make no mistake, the real costs are being passed on to someone somewhere.

Some in business, finance and government now realise that nature’s decline represents as much of a rising risk for investors as the funding of oil, coal and gas. Most such fossil fuels can never be burned if we’re to stay within safe global temperatures.

Meanwhile, the circulation of money between companies, banks, pension funds, insurance companies, and even by governments using our taxes, is driving nature’s demise.

It's doing so by funding destructive development and operations: dams harming entire rivers, road schemes cutting across fragile nature zones, oil palm plantations replacing rainforests and mining and oil and gas operations polluting and scarring landscapes and sea beds.

Some funds also find their way to corrupt regimes, black markets and hired hands who oppress and even murder people who seek to defend nature, land and livelihoods.

Indeed, the huge flows of money behind these and other activities could be the main driver of nature's decline.

Threats to nature globally

Species have been disappearing at 50-100 times the natural rate. Current trends indicate that 34,000 plant and 5,200 animal species now face extinction. This includes 1 in 8 of the world's bird species.     The world’s forests are home to many species but about 45% of the planet’s original forests have been cleared. This has happened mostly during the past century. Replanting trees can help, depending on how it’s done. But forests are still being lost especially in the tropics and other biodiversity hotspots.

Biodiversity loss in Borneo

Borneo is one of the globe's most precious nature hotspots. But here the creep of oil-palm plantations means a fifth of rainforests have been cleared to produce palm oil – that’s used as an ingredient in biscuits, cakes, margarine and other processed foods.

Not all trees are the same. The new oil-palm plantations cannot support the rich and diverse range of plants, insects and animals in a naturally diverse rainforest. Borneo’s altered landscape may look lush and green but it’s no longer supporting as many species. One sign of a healthy natural ecosystem is a wide range of predators. Borneo is losing predators such as mongoose, otters, civets and sun bears. For now the Monitor lizards rule.

Loss of coral reefs and mangroves

Coral reefs are among the richest of ecosystems. Some 10% of the world’s reefs have been destroyed by direct damage and by pollution. A third of remaining reefs face bleaching and collapse in the coming 10-20 years.

Australia’s Great Barrier Reef is dying. The cause is a combination of dumping of waste, and land clearances for development and sugar cane plantations which mean soils and pesticides run off into the sea.

This is self-inflicted harm. The reef has been estimated to be worth AU$52 billion to Australia’s communities and businesses. The loss of the reef as a tourist attraction will affect 90% of those.

Similarly, half of the world’s coastal mangroves have been lost to development and damage. Their loss ruins vital nursery habitats for countless species and undermines mangroves’ vital role in lessening the effects of storm surges.

Threats to UK nature

Are you ready for this? Nature is also in trouble in the UK. In the past 50 years more than half of our wild species have declined. If the prime minister told parliament that 56% of the nation’s assets had declined, it would be front page news for weeks.

Litter, pollution and nature

Even if you don’t live near the sea the chances are that the beaches you might like to visit are littered with stuff that was first discarded in your street. Much of the litter dropped in towns and on roads gets washed or blown into rivers to eventually reach the sea.

Plastic pollution and nature

Plastic gets everywhere. It comes in many hazardous shapes and sizes – from single-use drinks bottles to packaging for toys, cosmetics and food.

Turtles mistake plastic bags for jelly fish and eat them. This blocks their systems and causes them to starve.

Even clothes now contain tiny plastic fibres that get washed into soils, waters and wildlife when we do the laundry. Those and other plastics can harm wildlife – and even end up in the fish and seafood we eat.

Building, development and nature

The growth and design of our towns and cities drives inefficient, wasteful use of land. Too many roads and infrastructure schemes are still being routed through precious habitats. The new high speed rail link (HS2) threatens more than 90 irreplaceable ancient woodlands.

Chemicals and nature

The widespread use of artificial pesticides and herbicides is just one reason why current farming methods are a main driver of nature’s decline in the UK.

It is claimed that we need intensive farming to feed the world. But that looks absurd when so much nature is harmed and about a third of food that is grown is wasted in the supply chain, or dumped by consumers.

Invasive species

The health of natural systems is also threatened when invasive non-native species take over from native species.

For example, Himalayan balsam is a lovely plant when it’s in the Himalayas. But in the UK it dominates river banks and crowds out other plants needed by bees, birds and other UK wildlife. Invasive creatures such as the Harlequin ladybird and Asian hornet also prey on native species.

Of course, change is unavoidable. And competition between species is part of the natural order of things. Some species do just go extinct – their time is up.

The question is whether this is happening naturally and in a way that maintains a healthy diversity of species. Or is human activity hastening nature’s decline to such an extent that it will no longer furnish us with the fundamentals for a healthy life – clean air, water, food, and a stable climate?

Naturally-occurring forest fires help regenerate forests. But fires caused by a carelessly-discarded cigarette are not the same.

The benefits of protecting nature

There is no silver-bullet solution to halting and then reversing nature’s decline. Turning things around will require lots of actions by lots of players.

The United Nations’ Global Biodiversity Outlook report is clear that “continuing with … our present patterns of behaviour, consumption, production and economic incentives will not allow us to realise the vision of a world with ecosystems capable of meeting human needs into the future.”

The report adds that ending threats to nature would

• reduce hunger and poverty
• improve human health
• support sustainable supplies of energy, food and clean water
• combat desertification and land degradation
• reduce our vulnerability to natural and climate change-related disasters.

That sounds like a great deal. Besides which, healthy nature is a prize in itself.

Changing the way we live

It’s not inevitable that nature must suffer for us all to make a living. It makes no sense to allow an economy to surge at the expense of nature. If anything, it’s a false promise: our economy and quality of life ultimately depend on a healthy, functioning environment.

The good news is that many millions of people are making it their business to push companies and governments to change their practices and policies, to switch investments from fossil fuels to clean energy and, for example, help bees and pollinators.

Other clever people are exploring ways to make life on Mars possible in case we drop the ball we call home.

Friends of the Earth would rather the rest of us focused on making all life on Earth possible. We have the brains, we have the means and each of us can play a part in making this happen. 

Why not join us to help us give nature a better chance?

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How do humans affect biodiversity?

Humanity impacts the planet's biodiversity in multiple ways, both deliberate and accidental. The biggest threat to biodiversity to date has been the way humans have reshaped natural habitats to make way for farmland, or to obtain natural resources, but as climate change worsens it will have a growing impact on ecosystems.

The main direct cause of biodiversity loss is land use change (primarily for large-scale food production) which drives an estimated 30% of biodiversity decline globally. Second is overexploitation (overfishing, overhunting and overharvesting) for things like food, medicines and timber which drives around 20%. Climate change is the third most significant direct driver of biodiversity loss, which together with pollution accounts for 14%. Invasive alien species account for 11%. 

Some models predict that climate change will become the primary cause of biodiversity decline in the coming decades. The impact of all the main drivers of biodiversity loss is accelerating and, as a consequence, so is the pace of biodiversity decline.

Growing demand for natural resources due to the increasing human population, more rapidly increasing per capita consumption and changing consumption patterns has meant that ever more natural habitat is being used for agriculture, mining, industrial infrastructure and urban areas.

Key areas of human activity causing biodiversity loss include:

• Deforestation. Tropical rainforests are particularly rich in biodiversity and are being destroyed
• Habitat loss through pervasive, incremental encroachment such as that caused by urban sprawl
• Pollution such as that associated with widespread pesticide use and overuse of fertiliser which are 6 and 12 times greater than they were before 1961 respectively
• It is estimated that half of the species at risk are threatened by agriculture
• Water use in some of the largest water catchments in the world where dams and irrigation reduce water flows
• Hunting and the over-exploitation of species such as in wild capture fisheries but also for wildlife trade
• Spread of invasive species and diseases through trade and travel 
• Climate change, as warming and changing rainfall patterns alters species ranges and the underlying water and chemical cycles which define current ecosystems 
• Pollution from plastic waste although its long-term effects on biodiversity are far from clear

For more on this issue visit: Amazonia’s future: Eden or degraded landscapes? | Royal Society ; Preserving global biodiversity requires rapid agricultural improvements | Royal Society ; and Past and future decline and extinction of species | Royal Society

Climate change and biodiversity

Human activities are changing the climate. Science can help us understand what we are doing to habitats and the climate, but also find solutions.

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Perspectives

The Science of Sustainability

Can a unified path for development and conservation lead to a better future?

October 13, 2018

• A False Choice
• Two Paths to 2050
• What's Possible
• The Way Forward
• Engage With Us

The Cerrado may not have the same name recognition as the Amazon , but this vast tropical savannah in Brazil has much in common with that perhaps better-known destination. The Cerrado is also a global biodiversity hotspot, home to thousands of species only found there, and it is also a critical area in the fight against climate change, acting as a large carbon pool.

But Brazil is one of the two largest soy producers in the world—the crop is one of the country’s most important commodities and a staple in global food supplies—and that success is placing the Cerrado in precarious decline. To date, around 46% of the Cerrado has been deforested or converted for agriculture.

Producing more soy doesn’t have to mean converting more native habitat, however. A new spatial data tool is helping identify the best places to expand soy without further encroachment on the native landscapes of the Cerrado. And with traders and bankers working together to offer preferable financing to farmers who expand onto already-converted land, Brazil can continue to produce this important crop, while protecting native habitat and providing more financial stability for farmers.

The Cerrado is just one region of a vast planet, of course, but these recent efforts to protect it are representative of a new way of thinking about the relationship between conservation and our growing human demands. It is part of an emerging model for cross-sector collaboration that aims to create a world prepared for the sustainability challenges ahead.

Is this world possible? Here, we present a new science-based view that says “Yes”—but it will require new forms of collaboration across traditionally disconnected sectors, and on a near unprecedented scale.

Download a PDF version of this feature. Click to see translated versions of this page.

I.  A False Choice

Many assume that economic interests and environmental interests are in conflict. But new research makes the case that this perception of development vs. conservation is not just unnecessary but actively counterproductive to both ends. Achieving a sustainable future will be dependent on our ability to secure both thriving human communities and abundant and healthy natural ecosystems.

The Nature Conservancy partnered with the University of Minnesota and 11 other organizations to ask whether it is possible to achieve a future where the needs of both people and nature are advanced. Can we actually meet people’s needs for food, water and energy while doing more to protect nature? 

The perception of development vs. conservation is not just unnecessary, but actively counterproductive to both ends.

To answer this question, we compared what the world will look like in 2050 if economic and human development progress in a “business-as-usual” fashion and what it would look like if instead we join forces to implement a “sustainable” path with a series of fair-minded and technologically viable solutions to the challenges that lie ahead.

In both options, we used leading projections of population growth and gross domestic product to estimate how demand for food, energy and water will evolve between 2010 and 2050. Under business-as-usual, we played out existing expectations and trends in how those changes will impact land use, water use, air quality, climate, protected habitat areas and ocean fisheries. In the more sustainable scenario, we proposed changes to how and where food and energy are produced, asking if these adjustments could result in better outcomes for the same elements of human well-being and nature. Our full findings are described in a peer-reviewed paper— “An Attainable Global Vision for Conservation and Human Well-Being” —published in  Frontiers in Ecology and the Environment .

These scenarios let us ask, can we do better? Can we design a future that meets people’s needs without further degrading nature in the process?

Our answer is “yes,” but it comes with several big “ifs.” There is a path to get there, but matters are urgent—if we want to accomplish these goals by mid-century, we’ll have to dramatically ramp up our efforts now. The next decade is critical.

Furthermore, changing course in the next ten years will require global collaboration on a scale not seen perhaps since World War II. The widely held impression that economic and environmental goals are mutually exclusive has contributed to a lack of connection among key societal constituencies best equipped to solve interconnected problems—namely, the public health, development, financial and conservation communities. This has to change.

The good news is that protecting nature and providing water, food and energy to a growing world do not have to be either-or propositions. Our view, instead, calls for smart energy, water, air, health and ecosystem initiatives that balance the needs of economic growth and resource conservation equally. Rather than a zero-sum game, these elements are balanced sides of an equation, revealing the path to a future where people and nature thrive together.

II. Two Paths to 2050

This vision is not a wholesale departure from what others have offered. A number of prominent scientists and organizations have put forward important and thoughtful views for a sustainable future; but often such plans consider the needs of people and nature in isolation from one another, use analyses confined to limited sectors or geographies, or assume that some hard tradeoffs must be made, such as slowing global population growth, taking a reduction in GDP growth or shifting diets off of meat. Our new research considers global economic development and conservation needs together, more holistically, in order to find a sustainable path forward.

What could a different future look like? We’ve used as our standard the United Nations’ Sustainable Development Goals (SDGs), a set of 17 measures for “a world where all people are fed, healthy, employed, educated, empowered and thriving, but not at the expense of other life on Earth.” Our analysis directly aligns with ten of those goals. Using the SDGs as our guideposts, we imagine a world in 2050 that looks very different than the one today—and drastically different from the one we will face if we continue in business-as-usual fashion.

A sustainable future is possible.

To create our assessment of business-as-usual versus a more sustainable path, we looked at 14 measurements including temperature change, carbon dioxide levels, air pollution, water consumption, food and energy footprints, and protected areas.

Over the next 30 years, we know we’ll face rapid population growth and greater pressures on our natural resources. The statistics are sobering—with 9.7 billion people on the planet by 2050, we can expect a 54 percent increase in global food demand and 56 percent increase in energy demand. While meetings these growing demands and achieving sustainability is possible, it is helpful to scrutinize where the status quo will get us.

The World Health Organization, World Economic Forum and other leading global development organizations now say that air pollution and water scarcity—environmental challenges—are among the biggest dangers to human health and prosperity. And our business-as-usual analysis makes clear what many already fear: that human development based on the same practices we use today will not prepare us for a world with nearly 10 billion people.

To put it simply, if we stay on today’s current path, we risk being trapped in an intensifying cycle of scarcity—our growth opportunities severely capped and our natural landscapes severely degraded. Under this business-as-usual scenario, we can expect global temperature to increase 3.2°C; worsened air pollution affecting 4.9 billion more people; overfishing of 84 percent of fish stocks; and greater water stress affecting 2.75 billion people. Habitat loss continues, leaving less than 50 percent of native grasslands and several types of forests intact.

However, if we make changes in where and how we meet food, water and energy demands for the same growing global population and wealth, the picture can look markedly different by mid-century. This “sustainability” path includes global temperature increase limited to 1.6°C—meeting Paris Climate Accord goals—zero overfishing with greater fisheries yields, a 90 percent drop in exposure to dangerous air pollution, and fewer water-stressed people, rivers and agricultural fields. These goals can be met while natural habitats extend both inside and outside protected areas. All signatory countries to the Aichi Targets meet habitat protection goals, and more than 50 percent of all ecoregions’ extents remain unconverted, except temperate grasslands (of which over 50 percent are already converted today).

Behind the Science

Discover how TNC and its partners developed the models for 2050.

III. What's Possible

Achieving this sustainable future for people and nature is possible with existing and expected technology and consumption, but only with major shifts in production patterns. Making these shifts will require overcoming substantial economic, social and political challenges. In short, it is not likely that the biophysical limits of the planet will determine our future, but rather our willingness to think and act differently by putting economic development and the environment on equal footing as central parts of the same equation.

Climate, Energy and Air Quality

Perhaps the most pressing need for change is in energy use. In order to both meet increased energy demand and keep the climate within safe boundaries, we’ll need to alter the way we produce energy, curtailing emissions of carbon and other harmful chemicals.

Under a business-as-usual scenario, fossil fuels will still claim a 76 percent share of total energy in 2050. A more sustainable approach would reduce that share to 13 percent by 2050. While this is a sharp change, it is necessary to stanch the flow of harmful greenhouse gases into the atmosphere.

The reduction in carbon-based energy could be offset by increasing the share of energy from renewable sources to 54 percent and increasing nuclear energy to one third of total energy output—delivering a total of almost 85 percent of the world’s energy demand from non-fossil-fuel sources.

Additionally, we will only achieve the full extent of reduced climate impacts if we draw down existing carbon from the atmosphere. This can be done through greater investment in carbon capture and storage efforts, including natural climate solutions—land management strategies such as avoiding forest loss, reforestation, investments in soil health and coastal ecosystem restoration.

The net benefit of these energy redistribution efforts is twofold. First, they lower the rate at which greenhouse gases are flowing into the air—taking atmospheric carbon projections down to 442 parts per million, compared to business-as-usual estimates that put the level closer to 520 ppm.

Second, these energy source shifts would create a marked decline in particulate air pollution. Our models show that the higher fossil fuel use in the business-as-usual scenario is likely to expose half the people on the planet to poorer air quality by 2050. Under the sustainable scenario, that figure drops to just 7 percent of the world’s inhabitants, thanks to lower particulate emissions from renewable and nuclear energy sources.

Case Studies: 

• Forests That Fight Climate Change: Brazil’s Serra da Mantiqueira region demonstrates how reforestation can tackle climate change, improve water supplies, and increase incomes in rural communities.  Learn More
• Can Trees Be a Prescription for Urban Health?:  Conservationists, community organizations and public health researchers joined forces to plant trees in Louisville, Kentucky and monitor their impact on air quality and residents’ health.  Learn More

Food, Habitat and City Growth

Meeting the sustainable targets we propose requires a second front on land to shift how we use available real estate and where we choose to conduct necessary activities. Overall, the changes we include in our more sustainable view allow the world to meet global food, water and energy demands with no additional conversion of natural habitat for those needs—an outcome that is not possible under business as usual.

While transitioning away from fossil fuels is essential to meet climate goals, new renewable energy infrastructure siting will present land-use challenges. Renewable energy production takes up space, and if not sited well it can cause its own negative impacts on nature and its services to people. In our more sustainable path, we address this challenge by preferencing the use of already converted land for renewables development, lessening the impact of new wind and solar on natural habitat. We also exclude expansion of biofuels, as they are known to require extensive land area to produce, causing conflicts with natural habitat and food security.

Perhaps most encouraging, we show that it is possible to meet future food demands on less agricultural land than is used today. Notably, our scenario keeps the mix of crops in each growing region the same, so as not to disrupt farmers’ cultures, technologies, capacity or existing crop knowledge. Instead, we propose moving which crops are grown where within growing regions, putting more “thirsty” crops in areas with more water, and matching the nutrient needs of various crops to the soils available.

Unlike some projections used by others, for this scenario we left diet expectations alone, matching meat consumption with business-as-usual expectations. If we were able to reduce meat consumption, especially by middle- and high-income countries where nutritional needs are met, reducing future agricultural land, water and pollution footprints would be even easier.

Meanwhile, on the land protection front, our analysis is guided by the Convention on Biological Diversity, the leading global platform most countries have signed. Each signatory country has agreed to protect up to 17 percent of each habitat type within its borders. While many countries will fall short of this goal under business as usual, it can be achieved in our more sustainable option.

By making changes in food, water and energy use, we can better protect nearly all habitat types.

We acknowledge 17 percent is an imperfect number, and many believe more natural habitat is needed to allow the world’s biodiversity to thrive. Looking beyond protected areas, we see additional differences in the possible futures we face. Our more sustainable option retains 577 million hectares more natural habitat than business as usual, much of it outside of protected areas. Conservation has long focused on representation—it is not only important to conserve large areas, but to represent different kinds of habitat. Under business as usual, we will lose more than half of several major habitat types by mid-century, including temperate broadleaf and mixed forests, Mediterranean forest, and temperate grassland. Flooded and tropical grasslands approach this level of loss as well.

But with the proposed shifts in food, water and energy use, we can do better for nearly all habitats in our more sustainable scenario. The one exception is temperate grasslands, a biome that has already lost more than 50 percent of its global extent today. In all, the more sustainable scenario shows a future that would be largely compatible with emerging views that suggest protecting half of the world’s land system.

 Case Study:

• Managing Sprawling Soy:  A partnership between businesses and nonprofit groups in Brazil will help farmers plant soy in the areas where it is has the smallest impact on natural habitats.  Learn More

Drinking Water, River Basins and Fisheries

Water presents a complex set of challenges. Like land, it is both a resource and a habitat. Fresh water resources are dwindling while ocean ecosystems are overburdened by unregulated fishing and pollution. Business-as-usual projections estimate that 2.75 billion people will experience water scarcity by 2050 and 770 water basins will experience water stress. Africa and Central Asia in particular would see fewer water stressed basins in the sustainable scenario.

Changes in energy sources and food production (see above sections) would lead to significant water savings by reducing use of water as a coolant in energy production and by moving crops to areas where they need less irrigation. Thanks to these changes, our more sustainable option for the future would relieve 104 million people and biodiversity in 25 major river basins from likely water stress.

Meanwhile, in the seas, we find an inspiring possibility for fisheries. Continuing business-as-usual fisheries management adds further stress to the oceans and the global food system as more stocks decline, further diminishing the food we rely on from the seas. But more sustainable fisheries management is possible, and our projections using a leading fisheries model shows that adopting sustainable management in all fisheries by mid-century would actually increase yield by over a quarter more than we saw in 2010.

And, while we know that aquaculture is a certain element of the future of fish and food, many questions remain about precisely how this industry will grow, and how it can be shaped to be a low-impact part of the global food system. Given these unknowns, we kept aquaculture growth the same in both our views of the future.

 Case Studies:

• Cities and Farmers Find Common Ground on Water: Smarter agricultural practices in the Kenya’s Upper Tana River Watershed are resulting in better yields for farmers and more reliable water supplies for the city of Nairobi.  Learn More
• Technology Offers a Lifeline for Fish:  A new mobile application being piloted in Indonesia is helping fill a crucial gap in fisheries management—providing accurate data about what species are being caught where.  Learn More

IV.  The Way Forward

This analysis does not represent a panacea for the growing need for economic development across the planet or for the environmental challenges that are ahead. But it does provide an optimistic viewpoint and an integrated picture that can serve as a starting point for discussion.

Our goal is to apply new questions—and ultimately new solutions—to our known problems. We present one of many possible paths to a different future, and we welcome like-minded partners and productive critics to share their perspectives with us. We encourage people from across society to join the conversation, to fill gaps where they exist, and to bring other important considerations to our attention. Most of all, we call on the development (e.g. energy, agriculture, infrastructure), health, and financial communities—among others—to work with us to find new ways of taking action together.

Ultimately, by illustrating a viable pathway to sustainability that serves both the needs of economic and environmental interests—goals that many have long assumed were mutually exclusive—we hope to inspire the global community to engage in the difficult but necessary social, economic and political dialogue that can make a sustainable future a reality.

Protecting nature and providing water, food and energy to the world can no longer be either-or propositions. Nature and human development are both central factors in the same equation. We have at our disposal the cross-sector expertise necessary to make informed decisions for the good of life on our planet, so let’s use it wisely. Our science affirms there is a way.

Join us as we chart a new path to 2050 by helping people and nature thrive—together.

Testimonials

Opportunities to Engage

Designing strategies to address global challenges for people and nature requires integration of diverse bodies of evidence that are now largely segregated. As actors across the health, development and environment sectors pivot to act collectively, they face challenges in finding and interpreting evidence on sector interrelationships, and thus in developing effective evidence-based responses.

Learn more about these emerging coalitions that offer opportunities to engage and connect with shared resources.

Bridge Collaborative

The Bridge Collaborative unites people and organizations in health, development and the environment with the evidence and tools to tackle the world’s most pressing challenges. Learn More

Science for Nature and People Partnership

SNAPP envisions a world where protecting and promoting nature works in concert with sustainable development and improving human well-being. Learn More

Wicked Econ Fest

Wicked Econ Fests are workshops between leading economics, finance, conservation and policy experts to tackle specific, decision-driven challenges. Learn More

Global Insights

Check out our latest thinking and real-world solutions to some of the most complex challenges facing people and the planet today. Explore our Insights

• Security Council

Climate Change ‘Biggest Threat Modern Humans Have Ever Faced’, World-Renowned Naturalist Tells Security Council, Calls for Greater Global Cooperation

Climate change is a “crisis multiplier” that has profound implications for international peace and stability, Secretary-General António Guterres told the Security Council today, amid calls for deep partnerships within and beyond the United Nations system to blunt its acute effects on food security, natural resources and migration patterns fuelling tensions across countries and regions.

Throughout the morning, the Council’s high-level open debate on climate and security heard from a range of influential voices, including naturalist David Attenborough, who called climate change “the biggest threat to security that modern humans have ever faced”.  In video remarks telecast at the outset, he warned that concentrations of carbon dioxide currently in the atmosphere have not been equalled for millions of years.

“If we continue on our current path, we will face the collapse of everything that gives us our security,” he said:  food production, access to fresh water, habitable ambient temperature and ocean food chains.  The poorest — those with the least security — are certain to suffer.  “Our duty right now is surely to do all we can to help those in the most immediate danger.”

While the world will never return to the stable climate that gave birth to civilization, he said that, if Governments attending the twenty-sixth Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC) in November recognize climate change as a global security threat, “we may yet act proportionately — and in time”.

Climate change can only be dealt with by unparalleled levels of global cooperation, he said.  It will compel countries to question economic models, invent new industries and recognize the moral responsibility that wealthy nations have to the rest of the world, placing a value on nature that “goes far beyond money”.  He challenged the international community to finally create a stable, healthy world where resources are equally shared and where — for the first time in history — people “come to know what it feels like to be secure”.

Mr. Guterres echoed those calls, describing the climate emergency as “the defining issue of our time”.  Noting that the last decade was the hottest in human history, he said wildfires, cyclones, floods and droughts are now the new normal.  “These shocks not only damage the environment on which we depend, they also weaken our political, economic and social systems,” he said.

Indeed, where climate change dries up rivers, reduces harvests, destroys critical infrastructure and displaces communities, it exacerbates the risks of conflict, he said.  A study by the Stockholm International Peace Research Institute found that 8 of the 10 countries hosting the largest multilateral peace operations in 2018 were in areas highly exposed to climate change.

The impact is greatest where fragility and conflict have weakened coping mechanisms, he said, where people depend on natural capital for their livelihoods and where women — who bear the greatest burden of the climate emergency — do not enjoy equal rights.  He highlighted examples in Afghanistan, where reduced harvests have pushed people into poverty, leaving them susceptible to recruitment by armed groups, and across West Africa and the Sahel, where changes in grazing patterns have fostered conflict between pastoralists and farmers.  In some Pacific small island nations, entire communities have been forced to relocate.

“The forced movement of larger numbers of people around the world will clearly increase the potential for conflict and insecurity,” he observed.  He called for greater efforts to address climate‑related security risks, starting with a focus on prevention, and creating a global coalition committed to achieving net-zero emissions by mid-century.  The United Nations is asking companies, cities and financial institutions to prepare credible decarbonization plans.

In addition, immediate actions are needed to protect countries from increasingly frequent and severe climate effects.  He urged donors and multilateral and national development banks to increase the share of adaptation and resilience finance to at least 50 per cent of their climate finance support.  Developed countries, too, must keep their pledge to channel $100 billion annually to the global South.  “They have already missed the deadline of 2020,” he acknowledged.

Above all, he called for embracing a concept of security that places people at its centre, stressing that COVID-19 has laid bare the devastation that non‑traditional security threats can cause on a global scale.  In all such efforts, it will be essential to build on the strengths of the Security Council, Peacebuilding Commission, international financial institutions, regional organizations, civil society, the private sector, academia and others.

Issuing a call to action, Nisreen Elsaim, Chair of the Youth Organization on Climate Change and the United Nations Youth Advisory Group, said young people around the globe are watching the Security Council as it grapples with climate change.  Each of the organ’s four meetings on the issue — in 2007, 2011, 2018 and 2019 — have referenced serious climate-related security risks in Somalia, Darfur, West Africa and the Sahel, Mali and the Lake Chad Basin.  “Science has forecasted many more countries will join this list if we did not take the right measures now, and if we did not start adaptation specially in Africa,” she said, adding that, in her country, “we are living in continuous insecurity due to many factors that put Sudan on the top of the list when it comes to climate vulnerability”.

She recalled that, in a 2018 Council resolution on Sudan, members recognized the adverse effects of climate change, ecological changes and natural hazards on the situation in Darfur, focusing specifically on drought, desertification, land degradation and food insecurity.  “Human survival, in a situation of resources degradation, hunger, poverty and uncontrolled climate migration, will make conflict an inevitable result,” she said.  Moreover, climate-related emergencies cause major disruptions in access to health, life-saving sexual and reproductive health services, and result in loss of livelihoods and drive displacement and migration.  They also increase the risk of gender-based violence and harmful practices and force young people to flee in search of a decent life.

Welcoming the Council’s recent deployment of a new special political mission, the United Nations Integrated Transition Assistance Mission in the Sudan (UNITAMS), she said it has a historic opportunity to speak to the root causes of the conflict.  Climate change and youth participation is mentioned twice in the Mission’s mandate, and climate change challenges are included in the 2020 Juba Peace Agreement.  Emphasizing that young people must be part of the solution, she declared:  “We are the present, we have the future, let’s not repeat previous generations’ lapse.”

In the ensuing dialogue, Heads of State and Government, along with ministers and other senior officials described national actions to attenuate the negative impact of climate change and offered their views on the related security risks.  Some pressed the Council to broaden its thinking about non-traditional security threats.  Several — including leaders from Kenya and Niger — stressed that the link between climate and conflict could not be more evident, while others explored the ability of Governments to meet people’s basic needs, and still others cast doubt on the assertion that the relationship between climate and conflict is causal, instead pointing to political and economic factors that are known to drive tensions.

Boris Johnson, Prime Minister of the United Kingdom and Council President for February, speaking in his national capacity, said the Council, while imperfect, has been willing to lead the way in confronting threats to international security.  “That is exactly what climate change represents,” he said, acknowledging that, while there are some who disagree, these cynics “could not be more wrong”.  While the causes of climate change may not sit within the Council’s traditional purview, its effects most certainly do.  He asked delegates to consider the young man forced onto the road when his once‑fertile home becomes a desert — one of the 16 million people displaced by weather-related disasters each year — who becomes easy prey for violent extremists, or the girl who drops out of school because her daily search for water takes her away from her family — and into the sights of the human traffickers.

“If such scenes were triggered by the actions of some despotic warlord or internecine conflict, few would question this Council’s right to act or its duty to do so,” he assured.  “This is not a subject from which we should shy away.”  The world must move from 51 billion metric tons of greenhouse‑gas emissions each year to net zero, so that the increase in global temperatures remains within manageable levels.  For its part, the United Kingdom Parliament passed a law committing to net zero by 2050, he said, drawing attention to his pledge that the nation would slash emissions by 68 per cent by 2030.  He urged the Council to act, “because climate change is a geopolitical issue every bit as much as an environmental one”, stressing that, if it is to succeed in maintaining peace and security worldwide, it must galvanize and support the United Nations family of agencies into a swift and effective response.

Kaïs Saïed, President of Tunisia , agreed with Ms. Elsaim that the world must listen to youth on climate change.  More broadly, humans — and not money — must be placed at the centre of the issue.  Voicing support for the Secretary-General’s 2021 priorities, especially his efforts to galvanize Member States to confront the multiple impacts of climate change, he described it as ironic that humans are, at the same time, the phenomenon’s drivers and its greatest victims.  “It is no one’s right to […] to commit all of humanity to death,” he stressed, noting that Council resolution 2532 (2020) confirmed that insecurity can be driven by a multitude of factors, not just armed conflict.  One such driver is the deepening poverty and resource scarcity resulting from a changing climate, particularly in Africa.  Climate factors often prolong conflict and create conditions conducive to deprivation, exclusion, terrorism and organized crime.

Calling on the Council to adopt a new, more comprehensive approach and for sufficient resources for all specialized agencies related to climate change, he underlined the need for early warning systems and better prevention strategies.  Noting that the COVID-19 pandemic and other recent crises have once again revealed the need for States to strengthen their solidarity, he emphasized the need for prompt action while stressing that the burden borne by States must be differentiated based on their degree of responsibility for causing the crisis.  Moreover, mitigation cannot be at the expense of developing countries, he said.

Uhuru Kenyatta, President of Kenya , said that new approaches to investment by the public and private sector need to reach the countries and regions worst hit by climate change.  Persistent droughts, constant sea‑level rise and increasingly frequent extreme weather patterns are reversing economic growth and development gains achieved over decades.  The result is increased fragility to instability and armed conflict that then come to the attention of this Security Council.  The implementation of the Council’s mandate to maintain global peace and security will only get more difficult with time if climate change remains on its present course.  Rather than wait for a future tipping point, we must redouble the efforts to direct all the resources and multilateral frameworks of our rules-based international order to mitigate the effects of climate change.  While the bulk of this work is happening outside the Council, no body with such a strong mandate should step aside from this challenge.

The climate-security nexus is already impacting Africa.  “Listen to us Africans when we tell you that the link is clear, its impact tangible and the need for solutions urgent,” he said.  Making recommendations, he said that the Council must do more when crafting mandates for conflict resolution and post-conflict resolution to ensure they dovetail with the efforts to deploy climate change mitigation and adaptation measures.  In this regard, he applauded Council resolutions 2349 (2017) and 2502 (2019), respectively on Lake Chad and the Democratic Republic of the Congo, that have integrated measures to address the impact of climate change.  The 15-member organ can also act strongly against illicit financial outflows, illicit resource exploitation, terrorism financing and money‑laundering in the most fragile regions in Africa.  Doing so immediately boosts the resources available to Governments to undertake climate change mitigation and offer the public services and goods needed to consolidate and protect peace.

Brigi Rafini, Prime Minister of Niger , agreed that the impact of climate change on peace and security is increasingly evident, stressing that water scarcity exacerbated by climate change could see gross domestic product (GDP) in the Sahel fall by 6 per cent and hunger increase 20 per cent by 2050.  Climate change has increased competition for diminished land and water resources, ramping up tensions between livestock owners and others.  He underscored the collective responsibility to tackle this existential challenge, stressing that “climate change and land degradation are no longer purely environmental matters”.  Rather, they are part of a broader view that links environmental goals with those for economic and social development, and the pursuit of international peace and stability.

“We need to consider climate change as a threat to peace and security,” he said, urging the Council to shore up its understanding of impact on security and to systematically consider climate change in its resolutions pertaining to specific country and regional contexts.  In such efforts, it should rely on the advisory role of the Peacebuilding Commission, and the Informal Expert Group on Climate and Security, co-chaired by Niger and Ireland.  The appointment of a Special Envoy of the Secretary-General for Climate and Security likewise will raise the profile of this dimension within the Council’s work.

Nguyễn Xuân Phúc, Prime Minister of Viet Nam , said the Earth’s recent calamities have placed great burdens on the political and socioeconomic life of many countries, causing unemployment and poverty, creating instability and exacerbating current conflicts.  Against that backdrop, the Council should galvanize the international community’s collective efforts with an approach that is balanced between traditional and non-traditional security challenges.  That includes addressing the root causes of conflicts such as poverty, inequality, power politics and unilateral interference and coercion.

Calling for strict adherence to the Charter of the United Nations and international law, he said the 2030 Agenda for Sustainable Development, the United Nations Framework Convention on Climate Change (UNFCCC) and the Paris Agreement on climate change must guide the way, and greater resources are needed to support developing countries, least developed countries, small island developing States and landlocked countries.  The Council should also enhance its early warning capacity, bolster its mediation and conflict prevention roles, work more closely with regional organizations and fully respect States’ sovereignty and national ownership.  Noting that Viet Nam is among the six countries most severely affected by climate change, he outlined various national efforts to address the challenge while requesting more international assistance.

Erna Solberg, Prime Minister of Norway , emphasized that climate change is redefining the global security landscape.  “We must rethink and adapt the Council’s approaches to peacebuilding and sustaining peace in three ways,” she said.  First, the Council needs better information on climate-related security risks.  International research networks and the informal expert group will be important in that regard.  Norway has helped establish a Nordic-Baltic expert network.  Second, the Council should discuss climate risks in specific country contexts, based on country reporting and briefings.  The United Nations must be at the forefront of preventive diplomacy.  To achieve sustainable solutions, peace diplomacy must be climate-sensitive, and climate action must be conflict‑sensitive.  Third, it is imperative to strengthen partnerships within and beyond the United Nations system, including with affected States and regional organizations.  The active participation of diverse groups, including women and youth, is also vital.

The national security communities in many countries have understood the security risks posed by climate change, she continued.  While climate change can lead to hard security challenges, there are no hard security solutions.  The first line of defence is ambitious climate action.  It must begin with the full implementation of the Paris Agreement and 2030 Agenda.  Climate action depends on multilateral cooperation.  By shouldering a common responsibility to counter climate change, the Council will be better prepared to maintain international peace and stability.

Ralph E. Gonsalves, Prime Minister and Minister for Foreign Affairs of Saint Vincent and the Grenadines , emphasizing that the Council has a responsibility to address the consequences of climate change, said a failure to do so would be, in part, “an abdication of our duty”.  It is time for the organ to seriously consider drafting a resolution on the matter and to map out a coherent approach, aiming for a working consensus.  Affirming UNFCCC’s role as the primary body for dealing with climate change and the Paris Agreement as a major part of the rules-based international system, he said the Council should play its role without encroaching on the work of UNFCCC’s inclusive decision-making body.  It should also engage with the Peacebuilding Commission and the General Assembly on climate and security risks that touch on issues of humanitarian support, sustainable development, health pandemics, peace and security.

Stressing that the first step to prevent or contain climate-security risks is for the major, and historical, emitters to fulfil — and indeed exceed — the commitments made in the Paris Agreement, he underlined the principle of common but differentiated responsibility.  Climate change is an existential threat that disproportionately affects the most vulnerable, especially small island developing States such as Saint Vincent and the Grenadines.  “It has become distressingly commonplace for an entire year’s [gross domestic product] to be washed away by a hurricane overnight, even as we are hindered by a lack of a sufficient inclusion, on favourable terms, into the global financial architecture,” he said.  Citing the many natural hazards in Haiti, in particular, he also drew attention to the Sahel region and the battle for dwindling resources.  However, no country is immune to such human-made challenges and all must stand in solidarity, with the Council paying close attention to climate change as it crafts its mandates, he said.

Kaja Kallas, Prime Minister of Estonia , said 7 of the 10 countries most vulnerable and least prepared to deal with climate change host a United Nations peacekeeping operation or a special political mission — a fact the Council cannot ignore.  She expressed support for the statement to be delivered by Germany’s Foreign Minister on behalf of like-minded countries pointing the way forward for the Council, stressing that “we need to acknowledge that the climate emergency can pose a danger to peace — and we must make it a part of our security policy planning and discussions here”.  She pressed the Council to “do more” to fully

aspects of its work, noting that the Secretary-General must receive a mandate to collect data and coordinate policy to this aim.

Among other efforts, she said that Estonia cooperates with small island States and least developed countries in green technology solutions and know-how transfer.  The Government also recently launched the Data for the Environment Alliance, a coalition of State and non-State actors that will support the United Nations Environment Programme (UNEP) in developing a global environmental data strategy by 2025.

Simon Coveney, Minister for Foreign Affairs and Defence of Ireland , said that climate change has many complex impacts, not least on international peace and security, the very business of this Council.  Climate change is already causing upheaval, affecting peace and security and the stability of societies.  Pointing out that the relationship between climate and security works in complex ways, he said political instability undermines efforts to build climate resilience, and the impact of climactic shocks is compounded when institutions are strained.  Ireland is proud to join the Weathering Risk Project to help guide action at the Security Council and beyond, and is keen to understand better not just how climate change contributes to insecurity but how climate action can build peace.  Ireland chairs the Informal Expert Group of Member States on this topic, together with Niger, also partnering with Nauru and Germany, as Chairs of the Group of Friends on Climate and Security.

Ireland’s core message today is that the inclusion of climate in Council discussions and actions will strengthen conflict prevention and support peacebuilding efforts.  Stressing the need to ensure the full, equal and meaningful participation of women and youth in decision-making processes related to climate issues and the management of natural resources, he declared:  “But, in listening to and understanding the concerns and insights of future generations, we cannot abrogate our responsibility to provide leadership today”.

Marcelo Ebrard Casaubón, Minister for Foreign Affairs of Mexico , said the COVID-19 pandemic has revealed that international peace and security can no longer be viewed through a single lens, but must also consider multiple drivers of insecurity.  Food insecurity, water scarcity and droughts — all exacerbated by climate change — have reached severe levels in several regions of the world.  Pledging Mexico’s support to the next Conference of Parties to the UNFCCC in Glasgow, later in 2021, he said climate change requires a comprehensive global response with a focus on ecosystem preservations.  Mexico recently submitted its own national plan in that arena, which is coupled with a focus on prevention and adaptation, as well as efforts to reduce inequality and strengthen communities.  Stressing that all efforts must be taken in line with the 2030 Agenda, he welcomed the Council’s creation of an informal group to monitor the links between climate and peace and security as a timely measure.  Underlining the importance of ensuring sustainable peacebuilding and protecting livelihoods, he agreed with the Secretary-General that post-pandemic recovery efforts are an opportunity to “build back better” and build more egalitarian, adaptable societies.

Emmanuel Macron, President of France , said protecting the environment has, in recent years, meant recognizing climate change as a peace and security issue.  Of the 20 countries most affected by conflict in the world, 12 are also severely impacted by climate change, he said, spotlighting the impacts of desertification, the increase in forced migration and agricultural challenges — all of which have resulted in such fallout as the advent of climate refugees and growing conflicts over land and water.  Endorsing the initiative to address such matters under the auspices of the Council, he echoed calls for the appointment of a United Nations Special Envoy for Climate Security, as well as for an annual Secretary-General’s report with relevant recommendations.

Recognizing that the effects of climate change are unfairly distributed worldwide, he recalled his recent call for France’s contribution to the Green Climate Fund to be increased to one third of its total.  France strongly supports the creation of a “Great Green Wall” in Africa, which aims to restore 250 million hectares of land for agriculture, create 10 million green new jobs and sequester carbon.  He also pledged France’s commitment to accelerating the preservation of biodiversity, while calling for strengthened dialogue between the African Union and the United Nations on climate and security.  Turning to the Pacific, where many nations are struggling to implement mitigation measures, he called for additional international support and an easing of geopolitical tensions across the region.

Prakash Javadekar, Minister for Environment, Forests and Climate Change of  India , recalled the global democratic effort to take climate action in a nationally determined manner, based on the principle of common but differentiated responsibility and respective capabilities.  He cautioned the Council against building a parallel climate track where such principles are “brushed aside”.  Noting that there is no common, widely accepted methodology for assessing the links between climate change, conflict and fragility, he said fragility and climate impact are highly context‑specific.  In fragile contexts, where Governments struggle to provide basic services, emergency conditions are largely driven by political violence disrupting harvests and aid supplies, rather than by climate factors alone.  “A complete picture of climate vulnerability only emerges with an assessment of the State’s capacity to be the primary responder to interrelated environmental, social, economic and security dynamics,” he said.  While climate change does not directly cause violent conflict, its interaction with other social, political and economic factors can exacerbate conflict drivers.  He called for the building of robust governance structures at local, national and regional levels to address climate‑ and fragility-related risks, pressing donor countries to provide greater financial, technological and capacity-building assistance to help fragile States enact adaption and mitigation strategies.

John F. Kerry, Special Presidential Envoy for Climate of the United States , thanked European and other countries for their leadership on climate change during what he described as the United States “inexcusable absence” from the debate over the past four years.  Though climate change is indeed an existential threat, the world has yet to adequately respond to it.  Noting that the question of climate change is no longer one for debate, he declared:  “The evidence, the science, is screaming at us.”  Many of the world’s regions most impacted by climate change are also projected to become future conflict hotspots.  Therefore, the issue must feature in all of the Council’s work and reporting.  Emphasizing that President Joseph R. Biden understands that “we do not have a moment to waste”, he cited his new coordinated, whole-of-Government approach which aims to elevate the issue and put the United States on the path to sustainability that can never be reversed by any future President or demagogue.

Addressing climate change will require every country to step up and boost their level of ambition, he said, noting that the world’s largest carbon emitters bear the greatest responsibility.  First and foremost will be the need to reduce the use of coal globally.  “Inaction comes with a far higher price tag than action,” he said, stressing that, not since the industrial revolution has there been such potential to build back better in every part of the globe.  Just by doing nothing, humanity will march forward in what is tantamount to a mutual suicide pact, he warned, spotlighting the importance of the climate summit to be hosted by President Biden in the coming weeks, as well as the Conference of Parties to the UNFCCC to be held in Glasgow later in 2021.  The United States will also work with like-minded countries in the Council, he said, urging Member States to begin treating climate change as the security crisis that it is.

Xie Zhenhua, Special Envoy for Climate Change of China , said that, even as global climate governance enters a new and crucial phase, the spread of COVID-19 poses serious threats to the global response.  Given the differences in historical responsibility and development levels between States, he underscored the principle of common but differentiated responsibility and urged developed nations to lead the way.  In building back after the pandemic, countries should respect nature, protect biodiversity, champion green lifestyles and “avoid old paths of giving without taking” from the Earth.  In that context, he described climate change as a development issue, urging the international community to support developing nations, least developed countries and small island developing States in implementing mitigation and adaptation measures.

“We need to stay committed to multilateralism,” he stressed, underlining the importance of UNFCCC and the Paris Agreement as the main channels for those critical discussions.  Any role to be played by the Security Council on climate change must fall under its purview, he added.  Outlining China’s commitment to fulfilling its responsibilities under the Paris Agreement, he spotlighted its recently announced plan to have national CO 2 emissions peak before 2030 and to achieve carbon neutrality prior to 2060.  He also pointed out that the country’s forest cover has been rising steadily for many years, that it leads the world in green power generation and that it tops the list of clean energy patents registered.

The representative of the Russian Federation agreed that addressing climate change requires a global approach that is coordinated, targeted at reducing emissions and implementing effective adaptation measures, especially through UNFCCC.  Noting that the Council has discussed climate change on several occasions, he said the issue is often presented as a fundamental threat to stability and as a root cause of problems, particularly in Africa, with warnings about the increasing risks of conflict.  While he agreed that climate change can exacerbate conflict, he questioned whether it is the root cause of violence.  “There are serious doubts,” he said.  The connection between climate and conflict can be examined only in certain countries and regions.  Discussing it in the global context is not relevant.  “Not all conflicts are threats to international peace and security,” he explained.  In addition, considering climate as a root cause of security issues distracts from the true root causes, and thus, hinders solutions.  Political and socioeconomic factors, which have a greater influence on conflict risk, cannot be ignored, he said, pointing out that COVID-19 has exacerbated inequalities within and between countries and sparked an uptick in hunger — including in countries that were already in conflict.  He urged donors to address the problem of “green protectionism”, seen in their refusal to exchange technology that would allow others to adapt.   While discussing climate issues in the Council is seen as beneficial, the “real work” of improving coordination of international activities would be better accomplished in the General Assembly, the Economic and Social Council and UNFCC.  Conflicts — in and of themselves — reduce the ability of States to adapt to climate change, he said, explaining that the increased security risks in the Sahel are, in fact, caused by countries pursuing regime change in Libya.

Lazarus McCarthy Chakwera, President of Malawi , speaking for the least developed countries, said building resilience to mitigate the security risks associated with climate change must begin with reflections on COVID-19, as Governments have relegated many other priorities in the quest to fight the virus.  Describing the impact of the nexus between climate change and security is “indiscriminate and consequential”, he said water scarcity, desertification and cyclones all foster competition for resources, and in the process, turn people into climate refugees.  Least developed countries bear the brunt of these phenomena, despite that their emissions are 30 times lower than those of high‑income countries.  Stressing that recovery from the coronavirus must be aligned with efforts to limit global temperature rise to 1.5°C, he pressed developed countries to approach the 2021 UNFCC meeting with more ambition than in years past, as their current commitments to cut emissions remain “woefully inadequate”.  They must fulfil their pledges to provide $100 billion in climate financing annually, answer the call to earmark 50 per cent of financing in the Green Climate Fund for adaptation, especially in least developed countries, and to meaningfully transfer climate‑friendly technologies to help least developed countries accelerate their green development efforts.

Gaston Alphonso Browne, Prime Minister and Minister for Finance and Corporate Governance of Antigua and Barbuda , spoke on behalf of the Alliance of Small Island States, declaring:  “Make no mistake […] climate change’s existential threat to our own survival is not a future consideration, but a current reality.”  For the past 30 years, the Alliance has been the single most consistent advocate on climate, he said, highlighting the often-overlooked threats faced by small island developing States.  He urged the international community to simultaneously plan and operationalize a system to address inevitable loss and damage which uproot peace and security of small island developing States.  Equitable solutions are needed to systematically address difficult issues, such as climate change displacement, including the treatment of climate refugees, and loss of territory. For the past three decades, small island and low-lying States have been sounding the alarm, sending the SOS distress signal.  They are losing their territories, populations, resources and very existence due to climate change.  The Secretary-General recently stated:  “Without nature’s help, we will not thrive or even survive[…] For too long, we have been waging a senseless and suicidal war on nature.”  Sadly, small island developing States continue to be the front line for this war.  “Our appeal for the Council is to take this threat very seriously before it is too late,” he said.

Heiko Maas, Federal Minister for Foreign Affairs of Germany , speaking for the Group of Friends of Climate and Security, said those countries are united by the common belief that climate change is the fundamental challenge of our time.  The poorest and most vulnerable are suffering the most, with entire islands at risk of disappearing.  “We are putting their future, their safety and their well‑being at risk if we don’t act,” he stressed, calling for concerted efforts by the United Nations in making climate change its top priority.  Agreeing with other speakers that the issue has major implications for peace and security, he said it therefore belongs firmly on the Council’s agenda.  In July 2020, the Nauru delegation presented the organ with a plan of action, including calling for the appointment of a Special Envoy on Climate and Security; regular reporting to the Council; climate‑sensitive peacebuilding; and more cooperation with civil society, regional and national actors on climate-related security risks.  Now, it is time for the Council to adopt a strong resolution reflecting each of those points, he said.

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The Nature vs. Nurture Debate

Genetic and Environmental Influences and How They Interact

Verywell / Joshua Seong

• Definitions
• Interaction
• Contemporary Views

Nature refers to how genetics influence an individual's personality, whereas nurture refers to how their environment (including relationships and experiences) impacts their development. Whether nature or nurture plays a bigger role in personality and development is one of the oldest philosophical debates within the field of psychology .

Learn how each is defined, along with why the issue of nature vs. nurture continues to arise. We also share a few examples of when arguments on this topic typically occur, how the two factors interact with each other, and contemporary views that exist in the debate of nature vs. nurture as it stands today.

Nature and Nurture Defined

To better understand the nature vs. nurture argument, it helps to know what each of these terms means.

• Nature refers largely to our genetics . It includes the genes we are born with and other hereditary factors that can impact how our personality is formed and influence the way that we develop from childhood through adulthood.
• Nurture encompasses the environmental factors that impact who we are. This includes our early childhood experiences, the way we were raised , our social relationships, and the surrounding culture.

A few biologically determined characteristics include genetic diseases, eye color, hair color, and skin color. Other characteristics are tied to environmental influences, such as how a person behaves, which can be influenced by parenting styles and learned experiences.

For example, one child might learn through observation and reinforcement to say please and thank you. Another child might learn to behave aggressively by observing older children engage in violent behavior on the playground.

The Debate of Nature vs. Nurture

The nature vs. nurture debate centers on the contributions of genetics and environmental factors to human development. Some philosophers, such as Plato and Descartes, suggested that certain factors are inborn or occur naturally regardless of environmental influences.

Advocates of this point of view believe that all of our characteristics and behaviors are the result of evolution. They contend that genetic traits are handed down from parents to their children and influence the individual differences that make each person unique.

Other well-known thinkers, such as John Locke, believed in what is known as tabula rasa which suggests that the mind begins as a blank slate . According to this notion, everything that we are is determined by our experiences.

Behaviorism is a good example of a theory rooted in this belief as behaviorists feel that all actions and behaviors are the results of conditioning. Theorists such as John B. Watson believed that people could be trained to do and become anything, regardless of their genetic background.

People with extreme views are called nativists and empiricists. Nativists take the position that all or most behaviors and characteristics are the result of inheritance. Empiricists take the position that all or most behaviors and characteristics result from learning.

Examples of Nature vs. Nurture

One example of when the argument of nature vs. nurture arises is when a person achieves a high level of academic success . Did they do so because they are genetically predisposed to elevated levels of intelligence, or is their success a result of an enriched environment?

The argument of nature vs. nurture can also be made when it comes to why a person behaves in a certain way. If a man abuses his wife and kids, for instance, is it because he was born with violent tendencies, or is violence something he learned by observing others in his life when growing up?

Nature vs. Nurture in Psychology

Throughout the history of psychology , the debate of nature vs. nurture has continued to stir up controversy. Eugenics, for example, was a movement heavily influenced by the nativist approach.

Psychologist Francis Galton coined the terms 'nature versus nurture' and 'eugenics' and believed that intelligence resulted from genetics. Galton also felt that intelligent individuals should be encouraged to marry and have many children, while less intelligent individuals should be discouraged from reproducing.

The value placed on nature vs. nurture can even vary between the different branches of psychology , with some branches taking a more one-sided approach. In biopsychology , for example, researchers conduct studies exploring how neurotransmitters influence behavior, emphasizing the role of nature.

In social psychology , on the other hand, researchers might conduct studies looking at how external factors such as peer pressure and social media influence behaviors, stressing the importance of nurture. Behaviorism is another branch that focuses on the impact of the environment on behavior.

Nature vs. Nurture in Child Development

Some psychological theories of child development place more emphasis on nature and others focus more on nurture. An example of a nativist theory involving child development is Chomsky's concept of a language acquisition device (LAD). According to this theory, all children are born with an instinctive mental capacity that allows them to both learn and produce language.

An example of an empiricist child development theory is Albert Bandura's social learning theory . This theory says that people learn by observing the behavior of others. In his famous Bobo doll experiment , Bandura demonstrated that children could learn aggressive behaviors simply by observing another person acting aggressively.

Nature vs. Nurture in Personality Development

There is also some argument as to whether nature or nurture plays a bigger role in the development of one's personality. The answer to this question varies depending on which personality development theory you use.

According to behavioral theories, our personality is a result of the interactions we have with our environment, while biological theories suggest that personality is largely inherited. Then there are psychodynamic theories of personality that emphasize the impact of both.

Nature vs. Nurture in Mental Illness Development

One could argue that either nature or nurture contributes to mental health development. Some causes of mental illness fall on the nature side of the debate, including changes to or imbalances with chemicals in the brain. Genetics can also contribute to mental illness development, increasing one's risk of a certain disorder or disease.

Mental disorders with some type of genetic component include autism , attention-deficit hyperactivity disorder (ADHD), bipolar disorder , major depression , and schizophrenia .

Other explanations for mental illness are environmental. This includes being exposed to environmental toxins, such as drugs or alcohol, while still in utero. Certain life experiences can also influence mental illness development, such as witnessing a traumatic event, leading to the development of post-traumatic stress disorder (PTSD).

Nature vs. Nurture in Mental Health Therapy

Different types of mental health treatment can also rely more heavily on either nature or nurture in their treatment approach. One of the goals of many types of therapy is to uncover any life experiences that may have contributed to mental illness development (nurture).

However, genetics (nature) can play a role in treatment as well. For instance, research indicates that a person's genetic makeup can impact how their body responds to antidepressants. Taking this into consideration is important for getting that person the help they need.

Interaction Between Nature and Nurture

Which is stronger: nature or nurture? Many researchers consider the interaction between heredity and environment—nature with nurture as opposed to nature versus nurture—to be the most important influencing factor of all.

For example, perfect pitch is the ability to detect the pitch of a musical tone without any reference. Researchers have found that this ability tends to run in families and might be tied to a single gene. However, they've also discovered that possessing the gene is not enough as musical training during early childhood is needed for this inherited ability to manifest itself.

Height is another example of a trait influenced by an interaction between nature and nurture. A child might inherit the genes for height. However, if they grow up in a deprived environment where proper nourishment isn't received, they might never attain the height they could have had if they'd grown up in a healthier environment.

A newer field of study that aims to learn more about the interaction between genes and environment is epigenetics . Epigenetics seeks to explain how environment can impact the way in which genes are expressed.

Some characteristics are biologically determined, such as eye color, hair color, and skin color. Other things, like life expectancy and height, have a strong biological component but are also influenced by environmental factors and lifestyle.

Contemporary Views of Nature vs. Nurture

Most experts recognize that neither nature nor nurture is stronger than the other. Instead, both factors play a critical role in who we are and who we become. Not only that but nature and nurture interact with each other in important ways all throughout our lifespan.

As a result, many in this field are interested in seeing how genes modulate environmental influences and vice versa. At the same time, this debate of nature vs. nurture still rages on in some areas, such as in the origins of homosexuality and influences on intelligence .

While a few people take the extreme nativist or radical empiricist approach, the reality is that there is not a simple way to disentangle the multitude of forces that exist in personality and human development. Instead, these influences include genetic factors, environmental factors, and how each intermingles with the other.

Schoneberger T. Three myths from the language acquisition literature . Anal Verbal Behav . 2010;26(1):107-31. doi:10.1007/bf03393086

National Institutes of Health. Common genetic factors found in 5 mental disorders .

Pain O, Hodgson K, Trubetskoy V, et al. Identifying the common genetic basis of antidepressant response . Biol Psychiatry Global Open Sci . 2022;2(2):115-126. doi:10.1016/j.bpsgos.2021.07.008

Moulton C. Perfect pitch reconsidered . Clin Med J . 2014;14(5):517-9 doi:10.7861/clinmedicine.14-5-517

Levitt M. Perceptions of nature, nurture and behaviour . Life Sci Soc Policy . 2013;9:13. doi:10.1186/2195-7819-9-13

Bandura A, Ross D, Ross, SA. Transmission of aggression through the imitation of aggressive models . J Abnorm Soc Psychol. 1961;63(3):575-582. doi:10.1037/h0045925

Chomsky N. Aspects of the Theory of Syntax .

Galton F. Inquiries into Human Faculty and Its Development .

Watson JB. Behaviorism .

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Environmental Issues Essay for Students and Children

500+ words essay on environmental issues.

The environment plays a significant role to support life on earth. But there are some issues that are causing damages to life and the ecosystem of the earth. It is related to the not only environment but with everyone that lives on the planet. Besides, its main source is pollution , global warming, greenhouse gas , and many others. The everyday activities of human are constantly degrading the quality of the environment which ultimately results in the loss of survival condition from the earth.

Source of Environment Issue

There are hundreds of issue that causing damage to the environment. But in this, we are going to discuss the main causes of environmental issues because they are very dangerous to life and the ecosystem.

Pollution – It is one of the main causes of an environmental issue because it poisons the air , water , soil , and noise. As we know that in the past few decades the numbers of industries have rapidly increased. Moreover, these industries discharge their untreated waste into the water bodies, on soil, and in air. Most of these wastes contain harmful and poisonous materials that spread very easily because of the movement of water bodies and wind.

Greenhouse Gases – These are the gases which are responsible for the increase in the temperature of the earth surface. This gases directly relates to air pollution because of the pollution produced by the vehicle and factories which contains a toxic chemical that harms the life and environment of earth.

Climate Changes – Due to environmental issue the climate is changing rapidly and things like smog, acid rains are getting common. Also, the number of natural calamities is also increasing and almost every year there is flood, famine, drought , landslides, earthquakes, and many more calamities are increasing.

Above all, human being and their greed for more is the ultimate cause of all the environmental issue.

Get the huge list of more than 500 Essay Topics and Ideas

How to Minimize Environment Issue?

Now we know the major issues which are causing damage to the environment. So, now we can discuss the ways by which we can save our environment. For doing so we have to take some measures that will help us in fighting environmental issues .

Moreover, these issues will not only save the environment but also save the life and ecosystem of the planet. Some of the ways of minimizing environmental threat are discussed below:

Reforestation – It will not only help in maintaining the balance of the ecosystem but also help in restoring the natural cycles that work with it. Also, it will help in recharge of groundwater, maintaining the monsoon cycle , decreasing the number of carbons from the air, and many more.

The 3 R’s principle – For contributing to the environment one should have to use the 3 R’s principle that is Reduce, Reuse, and Recycle. Moreover, it helps the environment in a lot of ways.

To conclude, we can say that humans are a major source of environmental issues. Likewise, our activities are the major reason that the level of harmful gases and pollutants have increased in the environment. But now the humans have taken this problem seriously and now working to eradicate it. Above all, if all humans contribute equally to the environment then this issue can be fight backed. The natural balance can once again be restored.

FAQs about Environmental Issue

Q.1 Name the major environmental issues. A.1 The major environmental issues are pollution, environmental degradation, resource depletion, and climate change. Besides, there are several other environmental issues that also need attention.

Q.2 What is the cause of environmental change? A.2 Human activities are the main cause of environmental change. Moreover, due to our activities, the amount of greenhouse gases has rapidly increased over the past few decades.

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A cloak of smog gives Fresno, California, a hazy look. Smog, a hybrid of the words "smoke" and "fog," is caused when sunlight reacts with airborne pollution, including ash, dust, and ground-level ozone.

Urban Threats

Urbanization spurs a unique set of issues to both humans and animals.

The promise of jobs and prosperity, among other factors, pulls people to cities. Half of the global population already lives in cities, and by 2050 two-thirds of the world's people are expected to live in urban areas. But in cities two of the most pressing problems facing the world today also come together: poverty and environmental degradation.

Poor air and water quality, insufficient water availability, waste-disposal problems, and high energy consumption are exacerbated by the increasing population density and demands of urban environments. Strong city planning will be essential in managing these and other difficulties as the world's urban areas swell.

• Intensive urban growth can lead to greater poverty, with local governments unable to provide services for all people.
• Concentrated energy use leads to greater air pollution with significant impact on human health.
• Automobile exhaust produces elevated lead levels in urban air.
• Large volumes of uncollected waste create multiple health hazards.
• Urban development can magnify the risk of environmental hazards such as flash flooding .
• Pollution and physical barriers to root growth promote loss of urban tree cover.
• Animal populations are inhibited by toxic substances, vehicles, and the loss of habitat and food sources.
• Combat poverty by promoting economic development and job creation.
• Involve local community in local government.
• Reduce air pollution by upgrading energy use and alternative transport systems.
• Create private-public partnerships to provide services such as waste disposal and housing.
• Plant trees and incorporate the care of city green spaces as a key element in urban planning.

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• ENVIRONMENT AND CONSERVATION
• AIR POLLUTION
• URBAN PLANNING
• WASTE MANAGEMENT

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How to reduce human-caused environmental changes

The diversity on Earth aids the health and quality of human life. It provides the food we eat, the clothes we wear, and the air we breathe. But what do we do to serve the Earth? Human impact makes the environment less able to sustain life due to “human-induced rapid environmental changes.” There is no way to escape the effect we have, but there are ways to lessen it in order to protect the beauty of Earth and the many species that inhabit it.

Biology professor Blaine Griffen shares solutions to the five main drivers of human-induced rapid environmental changes:

1. Overexploitation of resources

Let’s take it back to the basics and reduce, reuse, and recycle. Recycling is the most familiar of the three solutions, but we should turn our focus to the other two to achieve the greatest positive impact. Learn how to reuse everyday items. DIY culture has promoted the ability to repurpose almost anything. Utilize the internet to find out what you can do. Reducing is effective economically and environmentally. One way we can reduce is by being extra cautious about the overexploitation of water. Don’t keep your water running and cut down on lawn sprinkler systems.

2. Habitat destruction

We are part of the ecosystem that we live in, so we must support it. The humans vs. nature predicament has never been a productive one and leads to a destructive mindset. Changing this mindset can lead you to be more mindful and respectful of hiking trails, your camping footprint, and nature in general. We are meant to enjoy the beauty of nature, but we should not feel entitled to abuse it.

3. Invasive species

Invasive species prove their destructive nature by causing extinctions, competing with other species, and reducing diversity in the ecosystems they invade, but they also cost the US economy approximately 120 billion dollars per year. Three easy combative measures we can take against invasive species include, never releasing pets into the environment, cleaning boats after removing them from the water, and planting native species in your yard.

4. Pollution

Whether it is trash, chemicals, or light, the whole Earth suffers from pollution, and, luckily, we can alleviate the problem through simple efforts.

Some solutions include:

• Avoiding excess use of pesticides and fertilizer. Following instructions helps to avoid infecting ground water and causing pollution. 
• Picking up litter so it isn’t ingested by animals or infecting waterways.
• Minimizing the use of outside lights. 
• Learning to enjoy nature quietly.  

5. Climate change

Broad scale problems like climate change aren’t easily solved, but simple efforts make a difference. Consider your modes of transportation, electricity use, and the benefits of buying locally. Making choices that consider the climate change problem are healthy for the planet and you.

We need to abandon the feeling of hopelessness we may feel in regards to environmental problems. We must work together to have the power to make change, otherwise nothing will get better.

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• Review Article
• Published: 13 October 2021

Infectious disease in an era of global change

• Rachel E. Baker   ORCID: orcid.org/0000-0002-2661-8103 1 , 2 ,
• Ayesha S. Mahmud 3 ,
• Ian F. Miller   ORCID: orcid.org/0000-0002-2673-9618 1 , 4 ,
• Malavika Rajeev 1 ,
• Fidisoa Rasambainarivo 1 , 2 , 5 ,
• Benjamin L. Rice 1 , 6 ,
• Saki Takahashi 7 ,
• Andrew J. Tatem 8 ,
• Caroline E. Wagner 9 ,
• Lin-Fa Wang   ORCID: orcid.org/0000-0003-2752-0535 10 , 11 ,
• Amy Wesolowski 12 &
• C. Jessica E. Metcalf 1 , 13  

Nature Reviews Microbiology volume  20 ,  pages 193–205 ( 2022 ) Cite this article

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• Infectious diseases
• Policy and public health in microbiology

The twenty-first century has witnessed a wave of severe infectious disease outbreaks, not least the COVID-19 pandemic, which has had a devastating impact on lives and livelihoods around the globe. The 2003 severe acute respiratory syndrome coronavirus outbreak, the 2009 swine flu pandemic, the 2012 Middle East respiratory syndrome coronavirus outbreak, the 2013–2016 Ebola virus disease epidemic in West Africa and the 2015 Zika virus disease epidemic all resulted in substantial morbidity and mortality while spreading across borders to infect people in multiple countries. At the same time, the past few decades have ushered in an unprecedented era of technological, demographic and climatic change: airline flights have doubled since 2000, since 2007 more people live in urban areas than rural areas, population numbers continue to climb and climate change presents an escalating threat to society. In this Review, we consider the extent to which these recent global changes have increased the risk of infectious disease outbreaks, even as improved sanitation and access to health care have resulted in considerable progress worldwide.

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Introduction.

In premodern times, colonization, slavery and war led to the global spread of infectious diseases, with devastating consequences (Fig.  1a ). Human diseases such as tuberculosis, polio, smallpox and diphtheria circulated widely, and before the advent of vaccines, these diseases caused substantial morbidity and mortality. At the same time, animal diseases such as rinderpest spread along trade routes and with travelling armies, with devastating impacts on livestock and dependent human populations 1 . However, in the past two decades, medical advances, access to health care and improved sanitation have reduced the overall mortality and morbidity linked to infectious diseases, particularly for lower respiratory tract infections and diarrhoeal disease (Fig.  1d ). The swift development of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine speaks to the efficacy of modern science in rapidly countering threats from emerging pathogens. Nevertheless, infectious disease burden remains substantial in countries with low and lower-middle incomes, while mortality and morbidity associated with neglected tropical diseases, HIV infection, tuberculosis and malaria remain high. Moreover, deaths from emerging and re-emerging infections, in comparison with seasonal and endemic infections, have persisted throughout the twenty-first century (Fig.  1c ). This points to a possible new era of infectious disease, defined by outbreaks of emerging, re-emerging and endemic pathogens that spread quickly, aided by global connectivity and shifted ranges owing to climate change (Fig.  1d ).

a | Examples of epidemic periods associated with different eras of human transportation (land, maritime and air travel) are shown. Overland trade networks and war campaigns are thought to have contributed to multiple epidemics in the Mediterranean in late classical antiquity (green), beginning with the Antonine plague, which reportedly claimed the life of the Roman emperor Lucius Verus 125 , 126 , 127 , 128 . Maritime transportation (red and grey) leading to European contact with the Americas and the subsequent Atlantic slave trade resulted in the importation of Plasmodium falciparum malaria and novel viral pathogens 129 . In modern times, air travel (purple) resulted in the importation of severe acute respiratory syndrome (SARS) coronavirus to 27 countries before transmission was halted 130 . b | In recent years, increases in air travel, trade and urbanization at global (left) and regional (right) scales have accelerated, indicating ever more frequent transport of people and goods between growing urban areas (source World Bank ). c | Log deaths from major epidemics in the twenty-first century (source World Health Organization ). d | Disability-adjusted life years lost from infectious diseases (source Our World in Data ). MERS, Middle East respiratory syndrome; NTD, neglected tropical disease.

Here, we review how recent anthropogenic climatic, demographic and technological changes have altered the landscape of infectious disease risk in the past two decades. In terms of climate change, we consider both the influence of recent warming and projected future changes. For demographic change, we include trends such as urbanization (Fig.  1b ), population growth, land-use change, migration, ageing and changing birth rates. For technological changes, we primarily consider advances that enable cheaper, faster global travel and trade (Fig.  1b ), as well as improved health care. We do not explicitly address economic change; however, economic changes, including economic development, are crucial drivers of these three factors: climate, demography and technology. We also do not explicitly discuss natural drivers of pathogen evolution or biological processes unless they interact with human-driven global change.

New infections chart a pathway beginning with emergence, followed by local-scale transmission, movement beyond borders and possible global-scale spread. Global changes may differentially affect the risk of emergence, the dynamics of disease within a local population and the global spread of diseases between populations. We provide an overview of each step, first considering features of recent global change that have altered the risks of spillover of viral, fungal, bacterial and apicomplexan (malaria) infections into human populations, then detailing how spread within human populations, driven by the seasonal dynamics of transmission, may be impacted by global change, of relevance to both emergent and established pathogens. Finally, we consider changes to the drivers of global spread, focusing in particular on travel, migration and animal and plant trade.

Pathogen emergence into human populations

Recent decades have seen repeated pathogen emergence from wild or domestic animal reservoirs into human populations, from HIV-1 and HIV-2, to the 1918 influenza virus, to Middle East respiratory syndrome coronavirus, to SARS-CoV-2 (refs 2 , 3 , 4 ). For a novel pathogen to become a threat to human populations, first, contact between humans and the animal reservoir must occur; the pathogen must either have or evolve (Box  1 ) the capacity for human-to-human transmission 5 ; and finally, this human-to-human transmission must enable expansion of the pathogen’s geographical range beyond the zone of spillover. Recent global changes have affected each of these steps.

Patterns of contact between human and wildlife reservoirs have increased as human populations move into previously unoccupied regions. Population growth and agricultural expansion, coupled with increasing wealth and larger property sizes, are driving factors for these interactions and the resulting habitat destruction. This may occur alongside behaviours that increase the potential for spillover, such as consumption of wild meat 6 , or intensifying contact between wild and domestic animal hosts. For example, Nipah virus has been identified in several bat populations, particularly flying foxes, but in 1999 caused a severe disease outbreak in Malaysia, primarily among pig farmers 7 . It is hypothesized that the spillover of Nipah virus from bats to pigs was driven by three factors related to global change: pig farms expanding into the bat habitat; intensification of pig farming, leading to a high density of hosts; and international trade, leading to the spread of the infection among other pig populations in Malaysia and Singapore 8 . Expanding agriculture and its intensification may create conditions that favour pathogen circulation within domestic animal (or plant) reservoirs via high-density farming practices 9 . Beyond creating opportunities for emergence of problematic livestock pathogens, this could also increase opportunities for evolution of novel variants of risk to humans in domestic animal reservoirs. This may occur alongside increasing risk to workers interacting with animal populations 10 as a result of work practices. Global increase in the demand for and resulting intensification of meat production will importantly drive these processes, and associated use of antibiotics in domestic animals has the potential to select for resistant strains of bacteria with potential to affect human health 11 .

The nature of human populations that are exposed to potential spillover is also changing. For example, the elimination of smallpox led to the cessation of smallpox vaccination, which may have enabled the expansion of monkeypox 12 . More generally, globally ageing populations may provide an immune landscape that is more at risk of spillover, as ageing immune landscapes are less capable of containing infectious agents 13 . The intersection between declining function of immunity at later ages 14 and globally ageing populations may increase the probability of pathogen emergence, but this remains conjectural and an important area for research. The changing global context may allow existing human pathogens to both evolve novel characteristics and expand in scope. Selection for drug resistance now occurs worldwide, and antibiotic resistance has and will evolve repeatedly 15 . As with antibiotic resistance, rapid global spread is commonplace for antimalarial resistance following evolution 16 .

Climate change may play a role in the risk from pathogen spillover. Changing environmental conditions can alter species range and density, leading to novel interactions between species, and increase the risk of zoonotic emergence 17 . A series of compounded environmental factors, including a long period of drought followed by extreme precipitation, is hypothesized to have driven an upsurge in rodent populations causing the emergence of pulmonary hantavirus in 1993 (ref. 18 ). Similarly, evidence suggests that populations of the black flying fox in Australia, a key reservoir of Hendra virus, have moved 100 km southward in the past 100 years owing to climatic changes. This shifting range likely caused Hendra virus to spill over into southern horse populations, and these horses subsequently infected humans 19 , 20 . Patterns of change are likely occurring in other bat populations globally but remain understudied — a clear cause for concern given the crucial role bat populations play as a reservoir host for several high-fatality pathogens 21 .

Rapid rates of urbanization in low-income and middle-income countries, and the increase in populations residing in crowded, low-quality dwellings, have created new opportunities for the emergence of infectious diseases (Fig.  2 ). Urbanization has promoted the emergence and spread of arboviral diseases such as dengue, Zika virus disease and chikungunya, which are transmitted by Aedes aegypti and Aedes albopictus mosquitoes that are well adapted to urban areas 22 , 23 , 24 . Population density appears correlated with the preference of Ae. aegypti for human odour, and hence the evolution of human-biting — the transmission pathway for arboviral disease 24 . However the role of urbanization in vector-borne disease spread is complex: the preference of the Anopheles spp. vector for rural environments may have led to a decline in the prevalence of malaria in urbanizing regions 25 . Nevertheless, dense and highly connected urban areas are potential hot spots for the rapid spread of diseases such as COVID-19 and SARS, and cities can serve as a catalyst for rapid local and global transmission.

Interactions between urbanization and infectious disease are complex, with increased urbanization driving both positive and negative changes to global disease burden.

Box 1 Global change and evolution of hosts and pathogens

Mutations constantly arise in the genomes of all species, from viruses to elephants. Some genetic changes may have no observable effects on fitness (and thus will be selectively neutral), but can be used to track pathogen spread; for example, to trace the impacts of global connectivity on an outbreak 70 . Some genetic changes will affect disease phenotypes, potentially increasing the transmissibility, virulence or immune escape of a pathogen lineage 133 . The degree to which such mutations increase in frequency or spread geographically will depend on the degree to which they increase fitness, as well as pathogen population dynamics, which may be modulated by the global change context. Increases in the density and geographical distribution of susceptible hosts (whether they be people, crops or livestock) may provide greater opportunity for novel variants to emerge 9 simply by amplifying pathogen populations and thus circulating mutations. While understanding the nuance of cross-scale selection (that is, how the selective context of the individual host translates into the selective context at the scale of populations) remains a challenging frontier 134 , it is likely that ageing populations or the presence of immunosuppressive pathogens might further modulate selection pressures. Indeed, it has been suggested that the emergence of more transmissible or less immune-vulnerable variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was enabled in part by selection processes occurring during chronic infections in immunosuppressed individuals 135 . Greater global connectivity leads to more frequent exchange of this genetic material between populations of the same or different species, potentially leading to the erosion of evolved or engineered host resistance and increased rates of pathogen evolution 136 . Associated spillover followed by spillback can create scenarios that facilitate amplification and potentially selection of problematic pathogen variants 137 , an issue highlighted by recent documentation of human to mink to human transmission of SARS-CoV-2 (ref. 138 ). Likewise, increased rates of pathogen importation provide increased opportunities for pathogen populations to evolve the ability to utilize novel vectors (as has been observed in the Americas for malaria 129 ). Increased population connectivity can also enable pathogens and their vectors to shift to novel host species, from infected mosquitoes travelling on boats or in planes to agricultural pathogens being inadvertently relocated. Hosts that have not previously been exposed to such pathogens, and thus have no co-evolved defences, yet are phylogenetically and/or genetically similar to the original host are often most at risk 139 , 140 , a fact that makes homogenization of crops 141 or livestock a concern. Novel pathogen introductions can have large-scale population and ecosystem impacts, of which one famous example is the extirpation of the American chestnut tree by chestnut blight 142 . Changes in selection pressure resulting from changes in health-care strategies (for example, introduction of vaccination) may have the potential to select for different pathogen characteristics, and could potentially drive the evolution of virulence in pathogens 143 , 144 .

Local-scale disease dynamics

Emerging, re-emerging and endemic pathogens in human populations may exhibit distinct dynamic patterns of spread at the local scale. These patterns will be governed by demographic factors, including the effects of human behaviour on transmission (for example, school terms drive transmission of many childhood infections 26 and sex-specific travel patterns may result in higher burdens of chikungunya in women in Bangladesh 27 ) and immunity (which, for immunizing infections such as measles and rotavirus infection, is, in turn, shaped by replenishment of susceptible individuals via births 28 , 29 and depletion by vaccination where vaccines are available 30 ). Transmission may also be affected by climatic variables acting spatially or over the course of the year in line with seasonal fluctuations 31 , 32 . Recent global changes have affected each of these drivers of local-scale dynamics (Fig.  3 ).

The table summarizes select recent global changes (rows) and their impacts on disease emergence, local-scale dynamics and global spread (columns). An example susceptible ( S ), infected ( I ), recovered ( R ) model is shown, where β represents the transmission rate and γ is the recovery rate.

As school attendance not only modulates transmission of childhood infections 26 but also shapes human mobility 33 , dramatic increases in rates of school attendance globally thus have the potential to substantially alter the dynamics of many infections. That this has yet to be documented is perhaps in part because this change has happened alongside expansion of access to vaccines that protect children against many of the relevant infections, as well as global declines in birth rates, which also facilitate control efforts by diminishing the size of the susceptible pool 34 . If the burden of disease is age specific, the intersection between immunity and shifting demography may be particularly marked: declining birth rates translate into a smaller pool of susceptible individuals and thus infected individuals, reducing the overall rate at which susceptible individuals become infected, and thus increasing the average age of infection or disease, as reported for dengue in Thailand 35 and rubella in Costa Rica 36 as these countries went through the demographic transition. Conversely, ageing populations may increase transmission; for example, longer shedding has been suggested with increasing age for SARS-CoV-2 (ref. 37 ).

Demographic changes to population size and density via urbanization may also affect dynamics. Influenza, for example, tends to exhibit more persistent outbreaks in more populous, denser urban regions 38 (Fig.  2 ). A similar pattern was reported in the early COVID-19 pandemic 39 . If demographic change has importantly altered the context of infectious diseases in recent years, arguably an even larger effect is caused by changes in the occurrence of immunomodulatory infections, which, in turn, may affect other infections. For example, the emergence of HIV has amplified the burden of tuberculosis 40 . Mass drug administration efforts have reduced helminth prevalence, which will have knock-on effects on the burden of other infections, such as malaria, which may be increased in individuals experiencing a heavy worm burden 41 ; both will also intersect with the efficacy of vaccination programmes 42 .

The climate plays a key role in driving the local-scale seasonal dynamics of many infectious diseases, which may thus be altered by global change in climatic conditions 43 , 44 . Considering these impacts requires recognizing that interactions with climate differ by pathogen type. For directly transmitted infections, the role of climate is revealed by marked latitudinal gradients in epidemic timing 32 , 45 . Several respiratory pathogens, including influenza virus, are more highly seasonal in temperate climates and exhibit greater year-round persistence in tropical locations 32 , 46 . Climate change is expected to lead to an expansion of these tropical patterns, with possible implications for pathogen evolution 43 , 47 . At the individual level, susceptibility to respiratory viral infections may be impacted by exposure to local air pollution, which is a concern for rapidly urbanizing locations, where urban air pollution may disproportionately affect low-income communities and communities of colour 48 , 49 . For example, non-Hispanic Black and Hispanic populations in the USA were found to have higher exposure to certain PM 2.5 components than non-Hispanic white populations 49 . At the same time, globally, a move to an urban location may bring benefits in terms of increased access to health care (Fig.  2 ).

For some bacterial and fungal diseases, climatic changes may affect the pathogen’s environmental reservoir. Incidence of coccidioidomycosis (valley fever), caused by inhalation of fungal spores of Coccidioides spp., is expected to increase with climate change as the region with optimal conditions for fungal spore production expands 50 . Climate change may also have played a role in the emergence of the drug-resistant fungal pathogen Candida auris . C. auris emerged in several continents at the same time and has been shown to have increased thermotolerance compared with other closely related fungal species, which perhaps evolved in response to global warming 51 , 52 . This increased thermotolerance may have enabled the pathogen to jump from its environmental habitat into an intermediary avian host, given the higher body temperatures of avian fauna, before infecting humans 52 .

Demographic change and technological changes may alter a host’s interaction with the environmental reservoir. Cholera, caused by the bacterial pathogen Vibrio cholerae , persists in the environment, particularly in aquatic settings. Changes to environmental conditions, including elevated sea temperatures, lead to increased reproduction of the pathogen and local epidemics 53 , with clear links to longer-term climate phenomena such as El Niño 54 . However, improved sanitation lowers the risk of exposure to V. cholerae and has led to a decline of the disease in many locations 53 .

For vector-transmitted diseases, biological traits of both the vector and the pathogen may be sensitive to climate. Many transmission-related life cycle traits of the mosquito (biting rate, adult lifespan, population size and distribution) and the pathogen (extrinsic incubation rate) are temperature sensitive, and oviposition patterns depend on water availability 55 . Consequently, the geographical range for dengue, malaria and other vector-borne diseases 56 , 57 , 58 is affected by the local climate, and there is substantial effort to understand how these ranges may change with climate change 59 , 60 , 61 . For certain vector-borne diseases such as Zika virus disease, climate change may lead to an expanded range 62 . However, for other diseases, such as malaria, climate change may shift the spatial range of the infection to higher latitudes 63 . As ever, the footprint of human interventions may loom larger than these changes in local conditions 25 .

At the local scale, one of the strongest footprints detectable on the dynamics of many endemic infections in recent years is declines in incidence associated with access to vaccinations 64 . However, the introduction of a vaccine does not imply immediate elimination. As vaccination coverage increases, measles outbreaks, for instance, follow a pathway towards elimination defined by declines in mean incidence but high variability in outbreak size 34 . Imperfect vaccine coverage may allow population susceptibility to increase such that substantial outbreaks can occur if the disease is reintroduced; for example, the 2018 measles outbreak in Madagascar, which led to more than 100,000 cases 65 . Improved surveillance of the landscape of population immunity, via serological surveys, could help determine gaps in vaccination coverage 66 .

Global spread

As local conditions alter demographically, or as a result of climate change potentially expanding the range of locations suitable to a particular pathogen or vector, increased global connectivity will enable pathogens to reach these new environments more rapidly (Figs  3 , 4 ). Here, we review the impact of global change on three forms of global connectivity — international travel, human migration and local-scale mobility, and the international trade of animals, animal products and plants — while considering the impact on infectious disease risk. Technological change over the past two decades has dramatically lowered the cost of international travel, while demographic change has led to heightened demand for inexpensive flights (Fig.  1b ). Demographic and climatic drivers have altered patterns of local mobility and regional migration, while rising demand and technological change have increased the trade of plants and animals. At the same time, an increasingly urban population is better connected than ever before to global travel networks (Fig.  4 ). These changes to global connectivity will present unique risk factors for infectious disease spread, enabling pathogens to travel further and faster than ever before.

a | The global international air travel network expanded substantially from 1933 to 2020 (data from WorldPop and ref. 131 ). b | Average monthly maximum temperature in 1970–2000) and difference between 2070–2100 and 1970–2000 averages (data from WorldClim , Shared Socioeconomic Pathway 3 (SSP3)). c | Population projections under SSP3 in 2010 and relative population change projected until 2100 (source NASA Socioeconomic Data and Applications Center (ref. 132 )). Part a adapted with permission from ref. 131 , OUP.

International travel

The late twentieth century and the early twenty-first century have been marked by technological developments enabling ever swifter movement of people and pathogens over large distances — from trains to planes, and an expanding international airline network (Fig.  4 ). The total number of airline passengers doubled from just below two billion in 2000 to more than four billion in 2019 (Fig.  1b ). This rampant increase in global connectivity brings with it new risks from emerging pathogens (Box  2 ). However, many endemic pathogens also circulate via transit routes: seasonal influenza circulation in the USA can be predicted by flight patterns 67 , 68 , with evidence that flight bans following the events of 9/11 caused a delayed outbreak, and a prolonged influenza season within the USA as measured by a 60% increase in the time to transnational spread 68 . Similarly, rapid global air travel is expected to have played a key role in the global spread of SARS-CoV-2. Genetic analyses demonstrate multiple introductions of SARS-CoV-2, driven by air travel, in the Middle East 69 , northern California 70 and Brazil 71 .

International travel can lead to the global spread of vector-borne diseases via the introduction of new vectors into regions with suitable environmental conditions or the introduction of new pathogens into native and invasive vector populations. Historically, vectors have been introduced via trade routes: ships are thought to have been key to the global dispersal of Ae. aegypti and Ae. albopictus , which then became established in locations with appropriate environmental conditions 72 , 73 . Anopheles gambiae , the primary vector of malaria in Africa, was introduced into Brazil in the 1930s and became established in a region with a climate similar to that of its native Kenya 74 . Although malaria was already endemic in Brazil at the time, An. gambiae proved a much more effective vector, leading to a severe outbreak and a costly (but successful) eradication campaign 73 . There has been relatively little documented evidence of the introduction of new vectors via air travel. This is likely due to the low probability of vectors surviving the flight, and disembarking in a suitable region, in sufficient numbers to establish and drive an epidemic 75 . However, cases of ‘airport malaria’, that is, malaria transmitted within international airports, even outside endemic regions, are rare but becoming more common 76 .

A more feasible scenario is that air travel can bring an infected human host into contact with a native or invasive vector population that then establishes local transmission. Climate change has driven a shift in the range of several key vectors, which may make this introduction more likely. The range of the biting midge Culicoides imicola , a vector of bluetongue virus, which causes disease in ruminants, has expanded over the past few decades from sub-Saharan Africa and the Middle East into Europe, bringing a wave of bluetongue epidemics 77 . Following this expansion, bluetongue virus then spread outside the range of C. imicola into native populations of Culicoides spp. in more northerly regions of Europe. In terms of air travel, the 2015 Zika virus disease epidemic in the Americas may provide a recent example of a pathogen spreading into a susceptible vector population, likely facilitated by high connectivity 78 . Zika virus is thought to have been introduced to Brazil from French Polynesia and vectored by Aedes spp., although the volume of air travel during this period makes it almost impossible to conclusively determine the origin 78 . Similarly, it is hard to pinpoint the pathway via which West Nile virus was introduced into the USA in the 1990s; however, transport by either shipping (transporting vectors) or aircraft (transporting a human host) is likely 79 . After introduction, West Nile virus spread in the native Culex spp. mosquito population. More broadly, climate change complicates the picture in terms of possible future introductions. As the range of locations with environmental suitability for certain vector species changes, successful introductions of pathogens into these vector populations may become more likely 80 . At the same time, changes to population structure (for example, via urbanization) may alter the suitability of an environment for vector reproduction (Fig.  2 ).

Box 2 Will there be another pandemic like COVID-19?

COVID-19 has had an unprecedented impact on both human lives and our society, and we will likely be dealing with the consequences for decades to come. As we reckon with these consequences, one concern is that a suite of global changes has increased the risk from emerging pathogens, such that pandemics similar to COVID-19 could be a more frequent occurrence. However, there are biological features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that have made the pathogen distinctly difficult to control, primarily the virus’s ability to spread asymptomatically and presymptomatically. Many pathogens do not exhibit these features, which may be a cause for cautious optimism going forward.

The expansion of regional and global air travel, along with the increasing development of high-speed railway networks, has resulted in a substantial degree of connectivity between human populations 73 . At the same time, land-use change and climate change may have increased the risk of pathogen emergence. In combination, these drivers imply an era where pathogens are more likely to emerge, and more likely to spread globally on emergence. However, while the last century bore witness to several pandemics (Fig.  1 ), SARS-CoV-2 is unrivalled in its rapid, global reach. A key question is why SARS-CoV-2 was so successful at spreading globally and whether this was due to recent increases in global connectivity as opposed to epidemiological and biological characteristics of the virus itself 145 .

A clear distinction between SARS-CoV-2 and other recently emerged pathogens (for example, SARS-CoV and Ebola virus) is that an individual infected with SARS-CoV-2 may become infectious before developing symptoms 146 . This presents a unique challenge from a disease control perspective. A standard approach for limiting the onward spread of a new outbreak is to isolate infected individuals when they show symptoms. Case isolation proved successful in mitigating earlier SARS 147 and Ebola virus disease 148 outbreaks. However, symptoms for SARS-CoV-2 infection likely occur after an individual is already infectious 146 . This possible presymptomatic spread limits the efficacy of case isolation interventions as by the time the infected individual is isolated, the person may have already spread the pathogen to others 149 . In the figure, we plot the time to infectiousness (latent period) against the time to symptom onset (incubation period) for four pathogens that have caused severe outbreaks in recent decades. When the latent period equals the incubation period (dashed line in the figure), symptoms occur at a similar time to infectiousness (for example, influenza). The shaded region to the right of this line in the figure indicates possible presymptomatic spread, which may be uniquely difficult to control.

The 2–3-day delay between infectiousness and symptom onset provides ample time for long-distance spread of the disease, given current transport networks (see the figure). Control policies, such as testing before travel, provide a more effective option in this context, yet developing and distributing a test takes time, during which time the disease may spread rapidly. The good news is that this presymptomatic spread appears somewhat unique to SARS-CoV-2, at least compared with other acute infections such as influenza, SARS and Ebola virus disease (Fig.  4 ). In comparison, asymptomatic spread explains some of the difficulty in controlling acquired immunodeficiency syndrome before antiretroviral measures were available.

Migration and local mobility

Human migration is an intrinsic component of population dynamics driven by socio-economic, political and environmental factors, and one that has undergone considerable upheaval in the modern era. It is estimated that globally the number of international migrants, those who intentionally relocate to a country other than their birth country, is almost 272 million, representing 3.5% of the world’s population. By contrast, temporary migration, often considered ‘seasonal migration’, is driven largely by economic patterns, including agricultural seasons that require short periods of intense labour. The rate of migration continues to increase owing to both social, economic, political and environmental drivers in origin countries and economic opportunities, physical safety and security in destination countries. Projections for migration are unclear, with the UN projecting stable rates after 2050 (ref. 81 ). However, climate change will likely provide an escalating push factor, with sea level rise and extreme weather events leading to forced migration from exposed regions 82 .

Given the movement of people between countries, there remain risks of introduction of infectious diseases, including those common and uncommon in the country of migration 83 . It is possible for a infectious disease common in the source country, such as latent tuberculosis, malaria, viral hepatitis and infection with intestinal parasites, to be imported via this mechanism 84 , 85 , 86 . For example, in many destination countries, a large proportion of cases of tuberculosis are observed in the foreign-born population. However, the ultimate impact of these introduction events will depend largely on the population-level susceptibility and environmental suitability for sustained transmission in the destination country. More importantly, migrant groups often have more limited access to health care, treatment and resources, particularly those displaced, who are often provided with limited options to safely seek care and treatment 87 . Minimizing the impact of these possible disease threats depends on providing appropriate health care to these high-risk groups that takes into account the multifaceted social, political and economic components 88 .

Within-country population mobility can also play a key role in disease spread; however, it is typically difficult to track these movements. Aggregated mobile phone data are a valuable tool for tracing patterns of local mobility and predicting future outbreaks 89 . In recent work, mobility data have been shown to be predictive of inequities in COVID-19 burden in the USA 90 . Similarly, population mobility was found to predict the spread of the 2011 dengue epidemic in Pakistan 91 , while local travel following the Eid holidays was found to predict the spread of the chikungunya outbreak in 2017 in Bangladesh 92 . As the trend of urbanization continues, mobility to and from dense urban centres (that is, megacities) will likely play a future role in local spread of infections 92 . Better tracking of within-country population mobility, using novel data streams, may present an opportunity for forecasting future outbreaks 93 .

Intensification of animal and plant trade

International trade has expanded rapidly in the modern era and has been matched by a global proliferation of infectious diseases affecting not only humans but also animals and plants 94 , 95 . Trade drives this pattern by facilitating the translocation of hosts and pathogens across the geographical and ecological boundaries that constrain their spread. The economic and environmental threats posed by trade-driven infectious diseases of plants and animals are increasingly being recognized, and calls for more stringent containment measures have intensified in recent years 96 , 97 .

Plant trade

Deliberate transport of plant products has existed since the emergence of trade. Increases in the speed of transport during modern times have allowed more live plant tissue, and as a result more viable pathogen propagules , to be transported over long distances. Combined with the intensification of trade at the global scale, this pattern has driven a rise in long-distance transmission and disease emergence 98 , 99 . Trade drives the emergence of novel plant diseases by creating novel interactions between hosts and pathogens 100 . One pathway through which this can occur is the introduction of novel pathogens to native plants. For example, Xylella fastidiosa , a generalist bacterium vectored by xylem-feeding insects, was introduced into Europe in 2013 from the USA, likely as a result of trade. In Italy, X. fastidiosa is causing an ongoing epidemic of ‘olive quick decline syndrome’, resulting in severe losses of an economically and culturally important crop 101 , 102 . Trade can also drive the emergence of plant disease by introducing novel hosts to native pathogens. Eucalyptus rust, a disease caused by the fungal pathogen Austropuccinia psidii , emerged when the pathogen transferred from its native South American hosts in the myrtle family (Myrtaceae) to non-native Eucalyptus trees (which also belong to the myrtle family) being grown on plantations 103 . The disease now threatens to ‘spill back’ into naive endemic Eucalyptus populations in Australia.

Animal and animal-product trade

Animal trade has contributed to multiple outbreaks and emergence events globally, which have had major consequences for the agricultural sector as a whole and pose substantial risk for animal and public health. Large numbers of livestock are traded annually between countries and may facilitate the spread of pathogens. Rift Valley fever, for example, is a zoonotic vector-borne viral disease causing abortion and high neonatal mortality in domestic ruminants. The disease is widespread on the African continent and has recently been detected in Saudi Arabia and Yemen. Live cattle movement between East Africa and the Arabian peninsula or from the Union of Comoros to Madagascar is thought to have contributed to the introduction of Rift Valley fever virus and caused outbreaks in these locations in 2000 (Arabian Peninsula) and 2008 (Madagascar) 104 , 105 .

Additionally, the trade of animal-derived products such as meat may enable the movement of pathogens over large distances and between continents. For instance, African swine fever is a highly contagious viral disease affecting several members of the family Suidae, including domestic pigs and wild boars. Infection by African swine fever virus may result in up to 100% morbidity and mortality in affected pig herds and substantial economic losses for producers. In 2007, the accidental introduction of African swine fever virus to Georgia led to the first outbreak of African swine fever in Europe since the early 1990s 106 . The virus, which used to occur primarily in sub-Saharan Africa, was allegedly introduced to the Caucasian peninsula through meat products contaminated with viruses closely related to the ones found in Madagascar, Mozambique or Zambia 107 . Despite efforts to contain the virus, the disease has spread to more than 20 countries in Europe and Asia 108 , 109 .

Similarly, in recent decades there has been an expansion in infections of Vibrio parahaemolyticus — a bacterial pathogen found in shellfish and the leading cause of seafood-related illness globally. The pathogen is endemic to regions of the US Pacific Northwest but has recently spread to other parts of the USA, Europe and South America 110 , 111 . The concerning increase in V. parahaemolyticus infection is expected to have several drivers connected to global change. Declines in sea ice have increased ship traffic through the Bering Strait, with cargo ships possibly transporting V. parahaemolyticus in ballast water. At the same time, increasing sea temperatures may have increased the global environmental suitability for V. parahaemolyticus in the marine environment 110 . Finally, dispersal of the pathogen may have occurred via increasing global trade in shellfish, with evidence suggesting possible dispersal via Manila clams introduced into Spain from Canada 111 . This combination of possible drivers speaks to the complexity of understanding infectious disease risk in an era of global change, and the necessity of exploring concurrent changes.

Transboundary spread of diseases through legal and illegal trade of live animals may also have important consequences for biodiversity on a global scale. For example, the amphibian trade contributed to the expansion of novel strains of the fungal pathogen genus Batrachochytrium into naive hosts, devastating wild amphibian populations globally 112 . Conversely, infectious diseases also hamper trade, resulting in indirect economic losses in affected populations. Foot and mouth disease virus is a major reason for trade restrictions on livestock. While endemic in certain countries in Asia and Africa, foot and mouth disease virus causes outbreaks in naive populations, resulting in large economic losses 113 . While trade is a major driver of pathogen spread, food animal production has transformed in recent history into large-scale intensified systems with high-density, genetically homogenous populations, ideal for pathogen emergence and maintenance 114 . Critically, animal production systems often serve as the interface between wild and human populations, and multiple viral spillover events have occurred at this nexus. Nipah virus spilled over from fruit bats to the domestic pig population multiple times before subsequently infecting humans 115 . Pandemic variants of human influenza A virus are often the result of reassortment between human and avian viruses, with both domestic poultry and wild birds posited to play a role 116 , 117 , 118 . A non-viral example is the spillover of antimicrobial-resistant pathogens from livestock into humans: intensive antibiotic use in industrialized and smallholder livestock production systems to promote growth and prevent infections has been linked to the emergence of antibiotic resistance in humans 119 . Tackling emergence and disease spread in animal systems will require rethinking both food animal production and global trade of animals.

A new era of infectious disease

In recent decades, declines in mortality and morbidity, particularly childhood mortality, have been one of the great triumphs of public health. Greater access to care, such as therapeutics (including antibiotics), improved sanitation and the development of vaccines 120 have been core drivers of this progress. Even as medical advances in the twenty-first century have spurred advances in population health, inequalities in access to these advances remain widespread between and within countries 121 . Reducing inequities in access to health care and improving surveillance and monitoring for infectious diseases in low-income and middle-income countries, and in underserved populations within countries, should be a priority in tackling pathogen emergence and spread.

While life expectancy continues to increase, and life years lost to infectious diseases decline, the new threat of infectious disease will likely come from emerging and re-emerging infections. Climate change, rapid urbanization and changing land-use patterns will increase the risk of disease emergence in the coming decades. Climate change, in particular, may alter the range of global pathogens, allowing infections, particularly vector-borne infections, to expand into new locations. A continued uptick in global travel, trade and mobility will transport pathogens rapidly, following emergence. However, there are counterpoints to this trend: the rapid growth of connectivity observed in the early twenty-first century may stabilize, and structural changes wrought during the COVID-19 pandemic may persist 122 . Increased investment in outbreak response, such as the recent formation of the WHO Hub for Pandemic and Epidemic Intelligence, could help mitigate the threat from future emerging infections. In addition, efforts to develop universal vaccines (that is, vaccines that engender immunity against all strains of influenza viruses or coronaviruses, for example) could provide a monumental leap forward in tackling present and future infections 123 .

A changing world requires changing science to evaluate future risks from infectious disease. Future work needs to explicitly address concurrent changes: how shifting patterns of demographic, climatic and technological factors may collectively affect the risk of pathogen emergence, alterations to dynamics and global spread. More forward-looking research, to contend with possible future outcomes, is required in addition to the retroactive analyses that typically dominate the literature. Increasing attention needs to be paid to pathogens currently circulating in both wild and domestic animal populations, especially in cases where agriculture is expanding into native species’ habitats and, conversely, invasive species are moving into populous regions due to climate change. As the battle against certain long-term endemic infections is won, institutional structures built to address these old enemies can be co-opted and adapted for emerging threats. At the same time, new technologies, including advances in data collection and surveillance, need to be harnessed (Box  3 ). There is much recent innovation around surveillance, from reinterpreting information available from classic tools such as PCR 124 to leveraging multiplex serology approaches to identify anomalies that might suggest pathogen emergence, and there is increasing interest in integrating multiple surveillance platforms (from genomic to case data) to better understand pathogen spread. Finally, future research needs to align with a global view of disease risk. In an increasingly connected world, the risk from infectious disease is globally shared. The COVID-19 pandemic, including the rapid global circulation of evolved strains, highlights the need for a collaborative, worldwide framework for infectious disease research and control.

Box 3 Big data for disease

Recent technological advances in collecting, sharing and processing large datasets, from satellite images to genomes, represent a new opportunity to answer critical questions in global health. However, challenges remain, including the uneven geographical distribution of available data as well as biases in representative sampling. We highlight three areas of future growth.

Serological surveys

Serological surveys detect the presence of antibodies in blood — recent advances in testing now enable the detection of exposure to multiple pathogens with use of a small sample of blood 150 . Serological surveys have attracted attention during the COVID-19 pandemic as a means to track population exposure given under-reporting, although test performance characteristics differ widely between epidemiological contexts as well as the choice of assay used 151 . Historically, serological surveys have been financially and logistically expensive to run, but declining costs are leading to increased availability of serological data.

Genomic surveillance systems

Genomic surveillance systems are able to characterize and track the emergence of novel variants (for example, during the COVID-19 pandemic). Undoubtedly these data have enabled the rapid development of diagnostics and vaccines and, when combined with epidemiological information, are able to provide a more detailed picture of ongoing transmission dynamics. Efforts to develop national and international genomic surveillance networks are varied but with clear success stories 152 , 153 even in low-resources settings 154 . However, resource limitations, including sequencing platforms, bioinformatic pipelines and the regular collection of samples for processing, continue to limit the global expansion of sequencing.

Artificial intelligence and machine learning

These techniques are frequently proposed as tools for answering key public health questions, yet specific use cases remain elusive 155 . Using these tools to predict viral emergence, for example, may prove difficult due to microbiological complexities and the cost of data collection 156 , yet could prove valuable for targeting sampling efforts 157 . In terms of uncovering population-level drivers of disease transmission, statistical approaches, including machine learning, can be used to leverage novel, and high-volume, data streams. However, more classical, mechanistic models may provide a more robust framework for projecting future outcomes for the disease system under demographic, technological and climatic change. Future work should aim to improve the integration of machine learning approaches within the traditional mechanistic modelling frameworks to rapidly and accurately assess prospective challenges.

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Acknowledgements

R.E.B. is supported by the Cooperative Institute for Modelling Earth Systems. R.E.B., C.J.E.M. and F.R. are supported by the High Meadows Environmental Institute at Princeton University. A.W. is supported by the US National Institutes of Health through the National Library of Medicine (DP2LM013102) and the National Institute of Allergy and Infectious Diseases (1R01A1160780-01) and a Career Award at the Scientific Interface from the Burroughs Wellcome Fund. Research in the L.-F.W. group is supported by grants from the Singapore National Research Foundation (NRF2012NRF-CRP001-056 and NRF2016NRF-NSFC002-013), the National Medical Research Council of Singapore (MOH-OFIRG19MAY-0011, COVID19RF-003 and NMRC/BNIG/2040/2015) and the Ministry of Education, Singapore (MOE2019-T2-2-130). A.J.T. is supported by the Bill & Melinda Gates Foundation (INV-024911). S.T. is supported by the Schmidt Science Fellows programme, in partnership with the Rhodes Trust.

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Rachel E. Baker, Ian F. Miller, Malavika Rajeev, Fidisoa Rasambainarivo, Benjamin L. Rice & C. Jessica E. Metcalf

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A correlated series of climate events associated with the warm phase of the El Niño Southern Oscillation cycle.

Pathogen units responsible for infection, such as a fungal spore or viral particle.

The mixing of genetic material of different pathogens within an infected cell.

The measurement of antibody responses to multiple pathogens simultaneously.

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Baker, R.E., Mahmud, A.S., Miller, I.F. et al. Infectious disease in an era of global change. Nat Rev Microbiol 20 , 193–205 (2022). https://doi.org/10.1038/s41579-021-00639-z

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Accepted : 17 September 2021

Published : 13 October 2021

Issue Date : April 2022

DOI : https://doi.org/10.1038/s41579-021-00639-z

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