How are we damaging our land and our waters?
“Surely we have a responsibility to leave for future generations a planet that is healthy and habitable by all species”Sir David Attenborough
Loss of natural resources
75% of the Earth’s land has now been severely altered by human actions such as industry and farming. Only 13% of the world’s oceans remain as wilderness, free from human influence and exploitation. Today, approximately 60 billion tonnes of renewable and nonrenewable resources are extracted globally each year from our ecosystems, nearly twice the figure from 1980. According to some studies we are producing wastes and using the Earth’s resources 70% more quickly than they can be absorbed or replenished, effectively using up our annual ecological budget by August each year.
“It’s very important to keep repeating these concerns [about the Amazon]. There are a number of tipping points, which are not far away. We can’t see exactly where they are, but we know they are very close. It means we have to do things right away. Unfortunately that is not what is happening. There are people denying we even have a problem.”Philip Fearnside, Professor at Brazil’s National Institute of Amazonian Research
Since the onset of agriculture about 12,000 years ago, the number of trees worldwide has dropped by 46% – that’s the loss of a staggering 3 trillion trees. Forest cover is now at only 68% of what it was in preindustrial times, and around 15 billion trees are now being cut down each year. In the temperate zone, we retain only 1-2% of the original forest cover. The majority of tropical deforestation is driven by our demand for just four commodities – beef, soy, palm oil, and wood products. Palm oil is found in a myriad of popular products such as soaps, shampoo, chocolate, bread and even crisps.
In the Amazon – home to one in ten known species – a lethal combination of human-caused burning and climate change have now resulted in the destruction of nearly one-fifth of the rainforest: 17% across the entire Amazon basin and approaching 20% in the Brazilian Amazon. Deforestation of the Brazilian Amazon is now occurring faster than three football fields a minute, pushing the world’s biggest rainforest closer to a dangerous tipping point beyond which it would not be able to recover. In July 2019 alone, Brazil lost an area of forest bigger than the size of Greater London.
Deforestation is not only severely compromising the Earth’s natural ability to protect us from the devastating impacts of climate change; it is actually making global heating worse. Natural processes such as tree growth remove about half of human carbon dioxide emissions from the atmosphere every year. In this way, trees act as what’s called a carbon ‘sink’. The fewer trees, the less carbon dioxide can be mopped up.
However, new research has found that due to higher temperatures, droughts and deforestation, trees in the tropics are now taking up a third less carbon than they did in the 1990s. Simon Lewis, Professor in the School of Geography at Leeds University, said: “We’ve found that one of the most worrying impacts of climate change has already begun. This is decades ahead of even the most pessimistic climate models. Humans have been lucky so far, as tropical forests are mopping up lots of our pollution, but they can’t keep doing that indefinitely. We need to curb fossil fuel emissions before the global carbon cycle starts working against us. The time for action is now.”
To make matters worse, when cleared trees are burnt, enormous quantities of stored carbon are released back into the atmosphere. It has been calculated that clearing carbon-rich forests releases the same amount of carbon every year as driving 600 million cars. Indeed, global deforestation is responsible for nearly a fifth of all greenhouse gas emissions.
Worrying new research has revealed that up to one fifth (20%) of the Amazon rainforest is now emitting more carbon dioxide than it absorbs, suggesting that it could be “showing the beginnings of a major tipping point”, past which the forest would lose its ability to renew itself. The authors had previously calculated that a tipping point could occur at around 20-25% deforestation (see section on tipping points). They warn that in the next 30 years, more than half of the Amazon could transform from rainforest to savanna. Indeed, another study has revealed that it is possible that the entire Amazon will rapidly decline and to go from a carbon ‘sink’ to a carbon ‘source’ within the next few decades.
If forests become sources of carbon rather than absorbers of it, their role would switch from one of slowing climate change, to one of amplifying it.
Forests and woodlands do more than capture carbon. They are also important across the globe in preventing floods, stopping soil erosion, cleaning air and water, providing habitats for wildlife and food and other resources for local people. Indeed, tropical rainforests are the most biodiverse areas on the planet. Losing these forests would greatly contribute to the loss of other species.
Intensive agriculture is by far the biggest driver of global deforestation and wildlife loss and is severely damaging our soils and waters.
Our soils hold around 70% of the planet’s land-based carbon. However, when soil is repeatedly ploughed, the ability of the small creatures and microorganisms within it to store carbon is compromised and vast quantities are released back into the atmosphere in the form of carbon dioxide. Conversely, compacting soil, for example by human traffic or livestock, also diminishes its capacity to hold carbon by creating oxygen-poor zones in the soil. (See action on soil degradation)
Intensive agriculture can also lead to the drying out of peatlands, which store twice as much carbon as all the world’s forests. (See section on loss of wetlands, peatlands and other natural ecosystems).
In addition, the nitrates released by chemical fertilisers can destroy wildlife in local rivers and lakes through a process called eutrophication. Plus, agricultural pesticides are strongly implicated in the declines of pollinators. Globally there has been a five-fold increase in pesticide use since 1950, with over 4 million tonnes sprayed annually. Screening in the US revealed that, from 1992-2014, toxicity for insects from pesticides in the environment increased 48-fold.
The IPCC estimates that, if the entire spectrum of food production were factored in – from growing crops to transportation and packaging – up to 37% of all greenhouse gas emissions come from the global food system. Switching over to less intensive farming techniques – requiring less heavy machinery, fewer chemical fertilisers and less international transport – would not only make a huge impact on global greenhouse gas emissions, but would help to restore our soils and our wildlife. Approaches such as organic farming can reduce damage to the natural world and degradation of soils and beneficial species such as pollinators, but must be combined with changes in diets to offset the lower yields.
“Nothing really compares to beef, lamb, pork, and dairy – these products are in a league of their own in the level of damage they typically do to the environment, on almost every environmental issue we track”Dr. Joseph Poore, environmental scientist at the University of Oxford
In addition, livestock have a huge impact on global heating. Firstly, the enormous amount of land required for the grazing of animals and the growing of animal-feed is acquired through the clearing of carbon-rich forests, releasing carbon dioxide back into the atmosphere. Secondly, cows and sheep release an enormous amount of methane – a powerful greenhouse gas – in their burps and farts. In a single day, the 1.5 billion cows on our planet produce around 680 billion litres of methane (some calculations make it more like 500-650 litres per cow per day, ie 975 billion litres in total!). Thirdly, livestock are responsible for 65% of all human-related emissions of nitrous oxide due to the use of fertilisers to grow feed and the production of animal waste. Nitrous oxide is an extremely potent greenhouse gas nearly 300 times more powerful than carbon dioxide.
Overall, replacing all animal products with plant-based products (and allowing the land freed up to regrow) would be the equivalent to reducing global greenhouse gas emissions by a staggering 28%. (It is often claimed that it is more like 50%, but that reasoning is scientifically flawed, as explained in this blog.) Indeed, deforestation, cow burps and farts, and fertilisers produce more greenhouse gases than all the world’s cars, lorries and planes put together.
In addition, keeping livestock is an extremely inefficient way to use the Earth’s land and its limited resources to feed us. More than four fifths of the world’s farmland is used for livestock, but livestock provide less than one fifth of the world’s calories – and only about one third of our protein. It’s not just about the land taken up by animals themselves. One third of the world’s croplands are currently being used to grow food for these livestock. It would be far more efficient to feed these crops directly to humans: approximately 90% of energy is lost between each stage in a food chain, so we could feed far more humans by eating crops directly rather than feeding them to livestock and then eating the livestock.
Indeed, it has been calculated that cutting out livestock and replacing the calories with plant products would free up 76% of the world’s agricultural land for reforestation, habitat restoration and other less intensive forms of agriculture.
Livestock farming also uses up precious water. Producing a kilo of beef requires 50 times more water than for a kilo of tomatoes, cabbages or potatoes, and a kilo of chicken requires 14 times more.
Farming cattle is particularly bad for the planet. Not only do cows take up an enormous amount of land, but for every 100 g of protein, beef produces up to 105 kg of greenhouse gases, while tofu produces less than 3.5 kg and nuts, peas and pulses produce even less. Grass-fed or organically farmed cows don’t actually help much: in fact they can actually make things worse as letting cows roam freely might be better for the cows but it uses up far more land.
“Soil is lost rapidly but replaced over millennia and this represents one of the greatest global threats for agriculture”Duncan Cameron, Professor of Plant and Soil Biology at the University of Sheffield
Increased deforestation, overgrazing and the use of chemicals are also causing severe damage to our soils. This process is exacerbated by increases in extreme weather events, such as extreme rainfall that causes fertile topsoil to be washed away into rivers, or increased erosion due to drought, winds, or high temperatures.
Indeed, erosion carries away 25 to 40 billion tonnes of fertile topsoil every year and a third of our soils are now classified as being moderately or highly degraded. It can take about 500 years to form just 2.5 cm of topsoil, yet we are currently losing soil 10-100 times faster than it can be regenerated. This problem is made worse by the fact that earthworms – creatures that usually play a key role in the restoration of degraded soils – cannot compensate for the loss of healthy soil as they too have been depleted by 80% or more by the chemicals used in intensive farming. The UK has some of the most degraded soils on Earth, with nearly 85% of fertile peat topsoil in East Anglia having been lost since 1850, and the remainder at risk of being lost over the next 30–60 years.
A whopping 95% of what we eat relies on healthy soils, so degradation of our soils is having a huge impact on global food production – see section on human impacts on global food production.
Loss of topsoil also leads to increased pollution, flooding and desertification.
Soil degradation also has a knock-on effect on global warming. Soils hold around 70% of the planet’s land-based carbon, mostly from dead plant or animal matter, which is processed and cycled by small animals and microorganisms, such as earthworms, bacteria and fungi. In fact, just a spoonful of healthy soil contains 6 billion microorganisms. However, when soil is repeatedly ploughed or compacted by heavy machinery or livestock, the ability of the soil’s biological communities to store carbon is compromised and vast quantities are released back into the atmosphere in the form of carbon dioxide. (See section on intensive agriculture).
Globally, it is estimated that agricultural soils have now lost up to 75% of the carbon they held before being used for agriculture. Or maybe more.
Loss of grasslands, mangroves, wetlands and peatlands
Humans have caused damage across all of the world’s natural ecosystems, including wetlands, grasslands, mountains, tundra, rivers, coastal zones, and oceans.
Natural and semi-natural species-rich grasslands are one of the most damaged ecosystems on Earth, with over 80% having been lost in northern Europe and North America alone in the last century. These grasslands host a unique range of wildlife, and can support low intensity livestock production as well as provide clean water and resources for poor rural communities globally.
An area of coastal ecosystems larger than New York City – nearly 1 million hectares – is destroyed every year, removing an important buffer from extreme weather for coastal communities and releasing carbon dioxide into the atmosphere.
In addition, more than 85% of the wetlands that were present in the 1700s have now been lost, due to a combination of natural factors (magnified by climate change) and human activities such as agriculture and rural development, with 50% of wetlands being lost in the last 100 years and 35% since 1970. Wetlands are extremely important to our planet as they provide natural protection from flooding, storms and hurricanes, as well as being stores of carbon. Wetland types found in coastal areas include salt marshes, bottomland hardwood swamps, fresh marshes, and mangrove swamps.
In the United States alone, coastal wetlands cover about 160,000 square km (40 million acres), and each square kilometre of wetlands along the Atlantic and Gulf Coasts is estimated to provide an average of $1.8 million worth of property protection. That’s an estimated $288 billion worth of storm protection provided to the United States by wetlands every year. Yet between 2004 and 2009, in the coastal areas of the Atlantic, Pacific, the Gulf of Mexico and the Great Lakes, wetlands were lost at an average rate of about 320 square km (80,000 acres) per year. Recent wetland losses are estimated to have increased the property damage from Hurricane Irma in 2017 by $430 million.
A whopping 35% of the world’s mangrove forests may have been lost between 1980 and 2000 and they are now at risk of extinction. Mangroves are amongst the most productive ecosystems on Earth, providing a unique habitat for many species and many benefits for human beings, such as coastal protection and fisheries. They are also a crucial carbon sink. Whilst just 0.7% of the world’s forests are coastal mangroves, they store up to 4 times as much carbon as tropical forests and provide approximately $2.7 trillion in benefits to humans every year. Since 2000, nearly one third of the world’s remaining mangroves have been lost, with their stored carbon being released back into the atmosphere.
Damaged peatlands – a type of wetland that occurs in almost every country on the globe, making up nearly half the world’s wetlands – account for about 10% of greenhouse gas emissions globally. Although peatlands cover only 3% of the world’s land, they are the largest natural organic carbon store on land, storing twice as much carbon as all the world’s forests. When peatlands dry out, due to global heating or drainage for agriculture, large amounts of carbon dioxide is released.
How are we polluting our waters?
We are also severely polluting our waters. Since 1980, there has been a ten-fold increase in plastic pollution, with now an estimated 300 kg of plastic entering the ocean every second. This adds up to a staggering 4.8-12.7 million metric tonnes of consumer plastics ending up in the world’s oceans each year. Plastic pollution has resulted in the presence of more than 100 million particles of macroplastics in only 12 regional seas worldwide, and 51 trillion particles of microplastic floating on the ocean surface globally. A recent study found that off the coast of Oregon, USA, there’s an average of 11 tiny pieces of plastic to every oyster. Nearly all of these microplastic pieces came from clothing fibres or abandoned fishing gear.
Unfortunately, recycling isn’t necessarily the answer to this problem. Shockingly, a huge proportion of ‘recycled’ plastic actually ends up in the ocean, buried in landfill or even being burned. Due to ocean currents, there are now areas in the ocean where enormous amounts of plastic collects in one place, resulting in huge ‘garbage dumps of the sea’. The Great Pacific Garbage Patch for example, which is halfway between Hawaii and California, contains more than 1.8 trillion pieces of plastic, weighs more than 43,000 cars and is three times the size of France.
Plastics are not the only pollutant in our seas and freshwaters. Pesticides, herbicides, detergents, industrial chemicals, oil and sewage also make their way into our waters, as well as soil eroded from the land by human activities. More than 80% of wastewater resulting from human activities is discharged into rivers or sea without any pollution removal. Nitrates from the use of agricultural fertilisers are now the most common chemical contaminant in our groundwater. Indeed, human activity now produces as much nitrogen on an annual basis as all the world’s natural processes combined. These nitrates can find their way into lakes and coastal waters, and along with phosphates, cause algal blooms which poison waters and dramatically reduce the growth of plants and fish through a process called eutrophication. In addition, 300-400 million tonnes of poisonous heavy metals, solvents, toxic sludge, and other wastes from industrial facilities are dumped annually into the world’s waters.
Flooding can exacerbate this problem, as it can cause chemicals from old mines to be swept up and dumped into rivers and onto farmland. For example, after floods in the UK in 2012, levels of lead were much higher in rivers and were sufficient to kill farm animals grazing on the land.
How are we polluting our air?
“There is an air pollution pandemic”Professor Thomas Munzel, Specialist in Interventional Cardiology, Risk Factors and Prevention, University Medical Centre of Mainz
According to the World Health Organisation, a staggering 9 out of 10 people on our planet breathe polluted air (that’s air containing high levels of pollutants), with most air pollutants that we are exposed to coming from the burning of fossil fuels. Indeed, air pollution is the world’s largest environmental cause of disease and premature death across the globe, being responsible for an estimated 7 million premature deaths each year, with 4.8 million dying from outdoor pollution, and the remainder from household pollution. Overall, air pollution kills more people each year than smoking.
The sources of air pollution vary across the world. In many places traffic emissions are now the major source of air pollution but other important sources include industry, coal-fired power plants, agriculture and households. People are also exposed to air pollution in their own homes through indoor burning of fossil fuels and biomass-based fuels such as wood for cooking, lighting and heating. Wildfires also dramatically worsen air pollution in broad areas.
Across Europe, toxic air results in nearly 800,000 early deaths each year. In the UK, air pollution results in 28,000 to 36,000 premature deaths a year and over 60% of people in England are living in areas which exceed the World Health Organisation’s legal limits for air pollution – with more than 40 towns and cities in the UK being at, or exceeding, these limits.
In London alone, two million people are living with illegal toxic air – of which more than 400,000 are children – and 32 out of 33 boroughs exceed legal air quality limits. Air pollution in London has been estimated to cause the deaths of 24 people every single day. The UK’s Environment Audit Committee found that the cost of the health impacts of air pollution was likely to exceed estimates of £8 to 20 billion.
For more information, see section on health threats from air pollution.
How are we destroying our wildlife?
Why should we care about the loss of our wildlife?
Not only do our fellow species have as much a right to exist as we do, nature also supports human life here on Earth in a multitude of ways. Insects pollinate our crops, and a range of animals eat the pests that would otherwise destroy the crops on which we rely. Animals, microbes and fungi decompose and recycle dead matter, enriching our soils and recycling nutrients. Robust wild plant communities can prevent floods, stabilise soil and provide clean water and air. Coastal salt marshes and mangroves buffer us against storm surges and flooding from the sea (see section on loss of grasslands, mangroves, wetlands and peatlands).
Most human communities depend wholly or partly on wild food from the sea and a whopping 3 billion people across the globe rely on wild-caught and farmed seafood as a primary source of protein. In many parts of the world, people obtain wild food, medicines and fuel from natural ecosystems. And, as described earlier, trees and other plants are critical in capturing carbon and storing it in their bodies or in our soils.
Forest elephants, like other large fruit eaters, play an important role in protecting us from climate change due to their role as ‘forest gardeners’. By feeding off smaller shrubs, they ‘thin’ the forest, helping larger slow-growing plant species to survive. These large trees trap and store huge quantities of carbon dioxide from the atmosphere. Forest elephants have been shown to represent a carbon storage service of $43 billion.
Decimation of plant and animal populations – and loss of species – is greatly compromising these and other benefits that we get from nature.
Loss of species
“Nature is declining globally at rates unprecedented in human history – and the rate of species extinction is accelerating, with grave impacts on people around the world now likely.”IPBES Report 2019
Habitat destruction, climate change, overconsumption and pollution, are having a huge impact on the animals, plants and other species that we share our planet with. In fact, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) warned that the current biodiversity crisis is on a par with the threat to humanity posed by climate change.
According to Sir Robert Watson, Chair of the IPBES: “The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever. We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide.”
Indeed, a report warns that a “biological annihilation” of wildlife is eroding the foundations of economies, livelihoods, food security, health and quality of life worldwide. The authors of a review of the findings of the largest assessment of the state of nature, write: “Human actions are causing the fabric of life to unravel, posing serious risks for the quality of life of people. Only immediate transformation of global business-as-usual economies and operations will sustain nature as we know it, and us, into the future.”
The latest Living Planet Index estimates an average decline of 60% in the population size of thousands of vertebrate species around the world. (To be clear, this is not quite the same as saying that the total number of vertebrates has fallen by 60%.)
Over the last century, 400 vertebrate species went extinct. The International Union for Conservation of Nature (IUCN) found that, of approximately 116,000 species assessed, more than a quarter were threatened with extinction, including 25% of mammals. The latest research shows that there are now 515 land vertebrate species on the brink of extinction – meaning that there are now fewer than 1,000 individuals left in the world – including the Sumatran rhino, the Espanola Giant Tortoise and several species of Harlequin frog.
In 2019, the IPBES Global Assessment used the information the IUCN had gathered on the proportions of known species found to be at risk, along with information on the number of species on Earth, to estimate that a staggering one million animal and plant species are now threatened with extinction due to human action, many within the next few decades.
The study gave the main direct causes of biodiversity loss as habitat change, direct exploitation (e.g. fishing, hunting and logging), invasive alien species, pollution, and climate change. Some skeptics and commentators have attempted to discredit this “one million” figure. In response, Dr Andy Purvis, lead author of the Global Assessment and Life Sciences Research Leader at The Natural History Museum London, has written an article explaining exactly how it was calculated.
Loss of fish, whales and dolphins
Across Europe, North Africa and Asia, since 1970 populations of great freshwater species, from catfish to stingrays, have plunged by a staggering 94%, mainly driven by alterations of the ecosystems in which they live. According to the UN Food and Agriculture Organization, a third of commercial fish stocks are being harvested at biologically unsustainable levels and 90% are fully exploited. The population of Pacific bluefin tuna, one of the ocean’s most ecologically and economically valuable predators, has also plunged by 94% from historic levels due to rampant overfishing. Fishing doesn’t just harm fish. In 2008 it was estimated that a minimum of 300,000 whales and dolphins were killed each year as a result of fisheries bycatch, a number which has likely doubled in the past 10 years, especially when deaths from shipping and habitat loss are also considered. Indeed, a new study has revealed that the fishing industry has seen a decline in the dolphin population in the Indian Ocean of almost 90%, related to the use of illegal ‘gillnets’ that are widely used by fishing companies across the world.
Loss of insects
“Insect decline should be of huge concern to all of us, for insects are at the heart of every food web, they pollinate the large majority of plant species, keep the soil healthy, recycle nutrients, control pests, and much more. Love them or loathe them, we humans cannot survive without insects.”Dave Goulson, Professor of Biology at The University of Sussex
“If we were to wipe out insects alone – just that group alone – on this planet – which we are trying hard to do – the rest of life and humanity with it would mostly disappear from the land and from within a few months”E.O. Wilson, Entomologist, Harvard University Research Professor Emeritus
Insects pollinate many of our crops, help fertilise the soil they grow in and help control outbreaks of crop pests and other organisms that cause disease in people and livestock. Insects and other small invertebrates are also important in decomposing and recycling dead organic matter – including biological waste – and are critical parts of food webs in all ecosystems.
Indeed, nearly 90% of the world’s flowering plants and at least 75% of global food crop types depend, at least to some extent, on pollinators. In fact, 70 of the 100 most important human food crops are pollinated by insects. While there are many important pollinating insects, such as bumblebees, beetles, hoverflies and butterflies, honeybees alone carry out a whopping 80% of crop pollination.
However, several studies have suggested that the numbers of insects are declining dramatically. A 27-year long monitoring study across Germany revealed a dramatic 76% decline in flying insect biomass between 1989 and 2013 (as shown in the figure below). Worryingly, the study took place inside nature reserves, which should be the best protected places.
Another study revealed “frightening” declines of insects and spiders in German grasslands and forests. Dutch scientists have found that butterfly numbers have fallen by an average of over 80% in the last 130 years. Hotter and more frequent extremes in temperatures having led to a “drastic decline” in numbers of bumblebees across Europe and North America.
Whilst some of these studies were somewhat restricted in terms of the species and locations they considered, casting some doubt on how broadly their conclusions could be applied, a global analysis shed more light on insect declines. This analysis suggested a more moderate, but still alarming decline in insect abundance on land by 9% per decade since the 1960s – amounting to around a 43% decline since then (but more in some places, less in others). This same study showed freshwater insects are increasing in abundance by about 11% per decade, probably as a result of attempts to clean up waters over the last few years.
Insect numbers are decreasing so much that as many as 10% of insect species may now be threatened with extinction (not 40% as has often been wrongly quoted) due to a wide range of pressures including habitat loss, agro-chemical pollutants and climate change.
Of the more than 800 species of wild bee across Europe (bumblebees, solitary bees and others), 7 are classified as critically endangered, a further 46 are endangered, 24 are vulnerable and 101 are near threatened. Losing wild bee species would have an enormous impact on pollination around the world, wiping out plant species, some of which we rely on for our food.
Ecosystems are like a giant game of Jenga: take a few pieces out from the bottom and the whole lot could come tumbling down. So it is essential that we now safeguard bees along with other insect pollinators.
As American Entomologist Professor E.O. Wilson said, it is “the little things that compose the foundations of our ecosystems, the little things that I like to say, run the world.”
Loss of wildlife in the UK
The State of Nature report found that the UK was “amongst the most nature-depleted countries in the world’‘, with 1 in 4 British mammals now at risk of extinction. It found that the average number of mammals has fallen by 26%, whilst 15% of species are under threat of extinction and 2% are already gone for good.The most recent report by the British Trust for Ornithology found that more than a quarter of British bird species are threatened, including the puffin, the nightingale, and curlew. Indeed, we are already seeing a catastrophic decline and impending local extinction of other much-loved residents of the English countryside such as cuckoos and sparrows. According to the Joint Nature Conservation Committee, a government advisory body, the UK is set to miss 14 out of 19 of its biodiversity targets for 2020.
In Europe, the average population size of farmland bird species has fallen by 55% in just the past three decades.
The Sixth Mass Extinction
“This isn’t just about losing wonders of nature. With the loss of even the smallest organisms, we destabilise and ultimately risk collapsing the world’s ecosystems – the networks that support the whole of life on Earth.”Sir David Attenborough
It’s not just how many species we are losing; it’s how fast we are losing them. Globally, species are going extinct at rates 100-1,000 times faster than the ‘background rates’ typical of Earth’s past. The 400 vertebrate species that went extinct in the last century should have taken about 800 to 10,000 years to disappear naturally. Amphibians are now disappearing at a rate between 1,000 to 45,000 thousand times faster than natural background rates.
Several studies have suggested that things are so bad that we are now entering the Earth’s Sixth Mass Extinction event. Mass extinctions are defined as times when the Earth loses more than three-quarters of its species in a geologically short interval, as has happened only five times in the past 540 million years or so.