The Great Wave of Apathy – Why we need get serious about biodiversity loss

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On 6 May 2019, the UN IPBES released a summary of its landmark global assessment report on biodiversity[1]. The warnings were stark – as a result of human activities, nature is declining at a rate unprecedented in human history, placing a million species at risk of extinction. Put simply, nature is in trouble, therefore we’re in trouble.

Such a grave conclusion from the most comprehensive assessment of biodiversity to date should have been a wake-up call. Instead, it barely got a mention on news programmes, at least in the UK. Granted, the release coincided with the birth of Prince Harry and Meghan Markle’s son – and who doesn’t love a royal baby – but still, some perspective please BBC.

Biodiversity loss is arguably just as great a threat to humanity as climate change. While climate change will almost certainly exacerbate biodiversity loss, if we solve one without the other, we’ll still be in trouble.

For example, say we somehow managed to sort climate change by building lots of fans that suck carbon dioxide from the air[2], hurrah. If we then proceeded to carry on as normal, before long we would be facing the threat of the collapse of nature, which could have similar consequences to climate change: food and freshwater shortages; mass displacement; crippling adaptation costs; and increased vulnerability to extreme weather.

Despite the significance of the threat posed by biodiversity loss, the issue hasn’t managed to capture the public’s attention in the same way as climate change. People have embraced specific aspects, such as plastic pollution and palm oil, but the wider issue is yet to have its own ‘Blue Planet II moment’. Perhaps this has to do with to our inherent sense of detachment from nature.

Modern life is convenient, far more convenient than at any other time in human history, but such convenience leads to detachment. In a single tap of a contactless card, we can exchange a fraction of our earnings for food wrapped in nice little packages, practically indistinguishable from other consumer goods. The transaction is so easy, we rarely stop to think about the associated impact on nature; even if we wanted to find out, it would take a lot of work to unravel.

Every second, tens of thousands of taps and clicks purchase goods across the globe; they patter like raindrops, accumulating to a tempest that can wipe out swathes of rainforest, deplete fish stocks, and plunder natural resources, whilst people carry on, mostly oblivious.

Some scientists now believe that we are at the start of the sixth mass extinction event, the first driven by human activities[3]. It might as well be called the “Great Wave of Apathy” – the extinction we sort of knew was happening but couldn’t summon the collective motivation to stop. It would make for a pretty lousy film compared to the fifth, nowhere near as dramatic as a giant asteroid slamming into Earth.

But there is still hope – if we collectively jolt awake from this slumber, there is still time to change course. To do so, we need to start treating biodiversity loss as seriously as climate change.

Happily, the solutions to biodiversity loss, such as stopping further deforestation and restoring degraded natural landscapes, have a mutually beneficial impact on mitigating climate change. So, it is not necessarily a case of prioritising one over the other.

Discussions about climate change should go hand in hand with biodiversity loss. In particular, we must be careful to avoid climate change solutions that exacerbate biodiversity loss. For example, policies that set binding targets on biofuels are thought to have inadvertently caused significant deforestation, which has adversely affected biodiversity[4].

This article discusses the drivers of biodiversity loss and the potential solutions. It covers:

  1. Why does biodiversity loss matter?
  2. The current state of nature
  3. What is causing biodiversity loss?
  4. Potential solutions
  5. What you can do to help

1. Why does biodiversity loss matter?

Humans are a product of the natural world – we evolved from nature and have been shaped by our surroundings. We have come a long way, but we are still highly reliant on nature; we are so specialised and well-adapted to our environment that we would be helpless if put in a different one. For example, plonk us on the surface of Mars without support and we would soon perish.

Technology can help us to survive in situations that our bodies couldn’t ordinarily handle. For example, astronauts can survive orbiting our planet for months at a time in the International Space Station (ISS). However, the ISS simply replicates Earth’s natural systems – such as regulating oxygen and carbon dioxide levels, water supply, waste management[5] – and is still heavily dependent on supplies from Earth. Further, the estimated cost of the ISS spread over its lifetime is US$7.5m per crew member per day[6].

So, whilst it is technically feasible to live without nature using artificial life support, the cost would be prohibitive. Even assuming we could reduce the cost of artificial life support massively, there is no way we could sustain our 7.7 billion (and growing) population.

Nature provides the basic conditions we need to survive for free – it regulates the air we breathe, pollinates our crops, recycles nutrients in the soil to maintain fertility, mitigates the impact of extreme weather and is a source of food, medicine and materials.

Biodiversity is also important to our quality of life and mental wellbeing. Several studies have found that spending time immersed in nature has measurable physiological and psychological benefits[7] – the Japanese created the concept of “Shinrin-Yoku” or forest bathing in the 1980s[8].

Biodiversity could even unlock future advances in technology and is an important insurance policy, for example through:

  • Engineering solutions – Engineers have long looked to nature for solutions. Brunel drew inspiration from a shipworm to design a tunnelling shield in the 1800s[9]; his creation was used to excavate the Thames Tunnel and the underlying concept is still used in tunnel boring machines today.  More recently, chief engineer Eiji Nakatsu refashioned the nose of the Shinkansen (a.k.a. bullet train) in the shape of a Kingfisher’s beak to overcome the problem of fast trains generating a loud boom when exiting a tunnel[10]. He also mimicked the design of owl feathers to redesign the train’s pantograph – he was a bit of a bird lover.
  • Medicines – Undiscovered species and natural compounds may hold the key to new medicines. Whilst most modern western medicines are produced synthetically, biomedical researchers still investigate natural compounds to create new medicines[11]. Biodiversity could, for example, hold the key to developing drugs to overcome antimicrobial resistance.
  • Food security – Domestic food crops were developed over time by crossbreeding wild varieties to select desirable traits. Due to intensive monoculture farming practices, we are now heavily reliant on a small number of domesticated varieties and so are exposed to large portions of our food supply being wiped out by disease (as has happened in the past). Biodiversity provides an insurance policy for developing new disease-resistant domestic varieties.

A seminal paper in 1997 attempted to put a value on benefits provided by the world’s ecosystems and natural capital. It estimated the value of tangible benefits provided by just 17 ecological systems to be US$33 trillion per year (on average)[12]. The study was updated for data up to 2011 and the estimate was revised upwards to US$125 trillion value per annum[13] – that’s more than the entire GDP of the world of c. US$85trillion in 2018[14].

We are pretty proud of our infrastructure, buildings and gadgets and we tend to dissociate ourselves with the natural world, but in reality, nature is still giving us a huge helping hand. It is a bit like a mother pushing her daughter on a swing – although the daughter feels like she’s flying all by herself, her mother is doing most of the work and gravity is doing the rest.

It is easy to take something for granted though when it has been there your whole life, not to mention that of your parents, grandparents and ancestors. The Holocene era spanning the last 10,000 years has been a period of remarkable stability in the history of the Earth. This has allowed life on Earth, including humans, to flourish – all of our recorded history is within this era.

It would be imprudent, however, to assume that it will stay like this forever. Humans are now so numerous and pervasive, that we are driving climate change at the same time as rapid biodiversity loss. Nature is resilient, but it is a complex web of linkages and relies on balance, which we have disrupted. When certain species fail, more pressure is placed on remaining life, leaving the entire ecosystem weaker – under sustained pressure, entire ecosystems can collapse.

For example, imagine a bed of sharp nails (pointy side up) – provided there are enough nails, you can lie down easily enough without injury, as your weight is distributed such that the pressure on any single nail is not enough to puncture your skin; but if you start taking out nails one by one and try again, well that’s going to end in tears.

The loss of the Golden Skiffia (a small fish) may sound mildly sad, but remote, like seeing on the global weather forecast that it is going to be stormy in Djibouti next week. However, if you look at the trend of the declining wild populations and read research that suggests that the sixth mass extinction is already underway, then the situation suddenly becomes more serious.

A mass extinction event could have similar consequences to some of the worst effects of climate change: food and freshwater shortages; displacement of millions of people; crippling adaptation costs; and reduced protection from natural disasters. It is unclear whether the human race could survive such an event over a sustained period. Even if we did, the world would be a pretty bleak place – it could take several million years until biodiversity is restored to its previous level[15].

2. The current state of nature

Nature is in a bad way, whichever way you look at it.

The population of wild vertebrate species has declined by 60% since 1970[16] and the rate of extinction in recent decades is as high as 1,000 times the natural background rate[17]. Scientists believe that these observations indicate that we are at the start of the Earth’s sixth mass extinction event[18].

The International Union for Conservation of Nature (IUCN) maintains a “Red List”, which assesses the extinction threat level of different species ranging from ‘least concerned’ to ‘critically endangered’.    In its latest update, the IUCN expanded its assessment to more than 100,000 species, almost 30% of which are threatened with extinction, 6% critically so[19]. Tellingly, not a single species was recorded as having an improved status. The extinction risk for different groups of species is summarised in the chart below.

Figure 1 – IUCN Red List – extinction risk by group of species

Source: “Summary for policymakers of the global assessment report on biodiversity and ecosystem services” (2019) UN IPBES. Based on data from the IUCN Red List.

Extrapolating the results of the Red List to the much larger ‘not evaluated’ pool suggests that up to a million species are threatened with extinction. Half of these extinctions could occur within decades, unless action is taken to reduce pressure on the natural world and restore habitats[20].

Iconic animals such as lions, elephants, tigers, rhinos and orangutans are all considered to be threatened species. Even the beloved koala is threatened as a result of extensive deforestation on Australia’s East Coast, mainly for livestock and timber.

If the current trend continues, it is likely that by the time today’s children have children, many of the popular animals in their storybooks will be as common in the wild as unicorns and mermaids.

Another recent study found that the insect population has declined rapidly in recent decades, with total biomass reducing at a rate of 2.5% per annum, mainly as result of intensive agriculture and widespread usage of chemical pesticides[21]. It is estimated that 40% of insect species are threatened with extinction over the next few decades. That’s concerning news for humanity, as over 75% of global crop types require pollinators to yield.

Tropical rainforests are also being lost at an alarming rate, with 2016-18 being the three worst years for deforestation since records began[22]. Rainforests are vital for biodiversity and are also a key ally in the fight against climate change, locking up vast amounts of carbon. The losses have mainly been driven by clearing for cattle, palm oil and cocoa plantations.

Deforestation of the Amazon – the world’s largest rainforest and home to more species than any other terrestrial ecosystem – has accelerated since Bolsonaro was inaugurated as the president of Brazil. The rate of deforestation increased by 88% in June 2019 compared to the same month last year[23]. This trend is expected to continue, as Bolsonaro has already loosened a number of environmental protections.

3. What is causing biodiversity loss?

In one word: humans. The rapid growth in the human population and our ever-increasing rate of consumption has had a detrimental impact on biodiversity.

The IPBES identified five key human-related drivers of the observed decline in nature. In order, they are:

  • Changes in land and sea use;
  • Direct exploitation (e.g. logging and fishing);
  • Climate change;
  • Pollution; and
  • Invasive species.

Each of these drivers are discussed in turn below.

i) Changes in land and sea use

The single largest driver of biodiversity loss for terrestrial and freshwater ecosystems is habitat destruction through changes in land use, predominately for the expansion of agriculture. Clearing of biodiverse rich rainforests in Brazil and South-East Asia for cattle and palm oil plantations respectively, has been particularly problematic.

Half of the world’s habitable land and almost three-quarters of available freshwater resources is dedicated to agriculture. Livestock takes up the lion’s share of that allocation – it uses almost 80% of all agricultural land, yet only provides 20% of the global calorie intake[24].

Some animals are more equal than others – the chart below shows the amount of land required to produce one gram of protein. Beef is the real standout, requiring almost 8 times more land than pork[25], which is why it has been such a prominent driver of deforestation. Beef also emits far more greenhouse gas emissions than any other source of protein (e.g. it is 6 times higher than pork). Beef should be thought of the coal of livestock.

Figure 2 – Land required to produce one gram of protein, by source

Source: Clark & Tilman (2017) “Comparative analysis of environmental impacts of agricultural production systems, agricultural input efficiency, and food choice”. Environmental Research Letters, Volume 12, Number 6. Sourced via Our World in Data https://ourworldindata.org/

Aside from agriculture, the following changes in land use have also had a negative impact on nature:

  • Expansion of housing – urban areas have doubled since 1992, with low density sprawling cities being particularly problematic.
  • Infrastructure – global expansion of road and rail networks have fragmented habitats, for example, Britain’s planned HS2 railway threatens over 100 irreplaceable ancient woods[26]. The proliferation of dams and irrigation has affected rivers, with two-thirds of the world’s longest rivers no longer flowing freely[27].
  • Mining – increasing demand for resources has led to continued growth of mining, which has destroyed key habitats.

ii) Direct exploitation

When it comes to marine ecosystems, you may be surprised to read that plastic pollution – which has recently captured the attention of the world – is not the biggest problem. Even when combined with other types of pollution, plastic waste doesn’t even make the top three.

The single largest threat to marine life is overfishing. David Attenborough – who was instrumental raising the profile of plastic pollution – emphasised this point during a speech at the World Economic Forum in January 2019. Over 30% of fish stocks are overfished, while a further 60% are being harvested to the maximum sustainable limit[28].

Exploitation of resources on land, such as logging, is the second largest driver of the decline in terrestrial ecosystems.

iii) Climate change

Climate change is the third largest driver of the decline of all types of ecosystems. You may be surprised it is not higher. However, this finding is based on the level of warming experienced to date; it is a not forward-looking measure. If climate change continues unabated, it will have a growing impact on biodiversity. I discussed the threat of climate change in detail in a previous article.

iv) Pollution

Pollution is the fourth largest contributor to the decline in nature for all ecosystems. Widespread dumping of toxic chemicals, heavy metals and other industrial waste is having a significant adverse effect on both marine and terrestrial life.

For example, run-off from chemical fertilisers used in the agricultural production has led to algal blooms, which suffocate other marine life and cause ocean ‘dead-zones’. One of the largest dead-zones is an area of more than 20,000 square kilometres in the Gulf of Mexico[29].

Plastic pollution is a growing problem, particularly for marine life – the amount of plastic pollution in the oceans has increased tenfold since 1980[30]. The impact of microplastics, which have already entered food chains, is not well understood at this stage.

v) Invasive species

The fifth largest driver of biodiversity loss is invasive species, which can have a detrimental impact on local ecosystems, particularly on islands and other remote and isolated areas.

One well-known (and self-inflicted) example of an invasive species is the cane toad in Australia, which even featured on an episode of The Simpsons[31].

In 1935, cane toads were deliberately introduced in an attempt to control the native cane beetle, which was attacking sugar cane crops. As it turned out, cane toads were pretty hopeless at controlling cane beetles (they couldn’t jump high enough reach them), but they were exceptionally good at proliferating. Cane toads multiplied and spread and can now be found in 4 states with a population of more than 200 million[32].

Cane toads are poisonous and are particularly problematic for native wildlife, who haven’t yet developed the instinctive knowledge to avoid eating them. Various methods have been trialled to control cane toads, including cane toad golf, with little success.

4. Potential solutions

Mitigating biodiversity loss needn’t be a choice between humans and wildlife – that is not the right way to look at the problem. If we took steps to change our consumption patterns and to limit future population growth, for example through improving global education rates, then there would be plenty of room for both humans and nature to thrive.

Rising to this challenge will not be easy, but for the sake of both nature and humanity, we simply must do it.  The human population has doubled since 1970 and so we have to adjust our way of life accordingly – like a lot of things people did in the ‘70s, actions that have a disproportionate impact on the environment are no longer acceptable.

Changing our diets

The single largest action that we could take to restore biodiversity is to eat less meat. As discussed previously, livestock uses almost 80% of all agricultural land yet produces only 20% of the global calorie intake. In addition, livestock produces almost a fifth of global greenhouse emissions[33]. Cutting our meat intake would have substantial benefits for both biodiversity and climate change.

A study commissioned by medical journal The Lancet recently led to the development of a science-based diet that focuses on both health and sustainability[34] – it is the first of its kind and has since been dubbed the ‘planetary diet’. The planetary diet calls for a significant reduction in red meat (a 77% reduction for Europeans) and sugar, replaced by higher consumption of vegetables, fruit, pulses and nuts.

Although the planetary diet (or similar) would go a long way to addressing biodiversity loss and would also help mitigate client change, it would be virtually impossible for democratic governments to encourage widespread adoption of a (mostly) plant-based diet. I can just see the protests “they may take our lives, but they’ll never take our… cheeseburgers”.

Perhaps a simpler and more effective measure would be to phase-out subsidies for livestock and fishing. The EU alone spends a fifth of its budget, or c£24bn of taxpayers’ money, to support livestock[35], while global subsidies for fisheries total US$35 bn (in 2009 dollars)[36]. As a result, meat and seafood are far cheaper than they should be.

Without subsidies, the price of meat and seafood would increase to a level that better reflects the cost of production[37]. Consumers would then naturally substitute meat for plant-based alternatives, thus achieving the net effect of adopting a healthier and more planet-friendly diet.

Further, the money saved from removing subsidies could be redirected to providing additional services, tax-cuts or even climate change and biodiversity mitigation programmes.

Cut food waste

Almost one-third of the food produced for human consumption is wasted[38]. In other words, a third of agricultural land is dedicated to producing food that is thrown out. Against a backdrop of declining biodiversity, runaway greenhouse gas emissions and a world where millions are starving, such wastage is egregious.

Globally, the majority of food waste occurs prior to reaching consumers, for example due to unrealistic aesthetic standards and uneconomic prices during supply gluts. However, consumers in developed countries also waste 40% of the food they purchase; the amount thrown away is equivalent to the total net food production of sub-Saharan Africa.

The seemingly obvious act of not wasting food would have a positive impact on both biodiversity and climate change. Think of all of the redundant farmland that could be used to plant trees and restore natural habitats.

Governments, producers and consumers all need to do their part to address food wastage and find more sustainable solutions – such excessive wastage cannot continue.

Creating protected zones for wildlife

Nature has shown it has the ability to recover if left alone. For example, while the 4km wide demilitarised zone (DMZ) dividing the two Koreas is a no-go for humans, it has become a haven for wildlife. A rare Asiatic black bear was recently photographed in the DMZ by an unmanned camera, indicating a healthy ecosystem. The DMZ is thought to be home to more than 5,000 different plant and animal species[39].

Now, that’s not to say the world needs more DMZs or disaster areas – creating national parks and marine sanctuaries would have the same effect. Dedicated conservation areas protect wildlife from destructive human activities, such as logging and fishing, and give nature the chance to recover.

One particular proposal that is close to my heart is the Great Forest National Park in my home state, Victoria, Australia. This park would protect a large section of Victoria’s native forests from a rampant and loss-making logging industry and would secure the habitat of the critically endangered Leadbeater’s Possum. The park is supported by Sir David Attenborough, Dr Jane Goodall and 70% of Victorian voters, yet the government still cannot seem find the courage to implement the proposal. 

Rewilding as a solution to biodiversity and climate change

Restoring natural habitats, or rewilding, would help slow biodiversity loss and capture carbon dioxide at the same time. Natural landscapes, such as forests, mangroves, peatlands and meadows have enormous potential to support biodiversity and store carbon.

A group called Rewilding Britain calls for farming subsidies to be redirected towards creating native woodlands and meadows[40]. It believes that up to a quarter of UK’s land could be restored to nature, making a significant contribution to cutting the nation’s greenhouse gas emissions to zero.

Following a similar theme, a group of scientists, artists and activists (including Greta Thunberg) wrote an open letter calling for rewilding as a solution to the climate change and biodiversity crises[41]. There is even an open UK parliament petition calling for rewilding as a solution – at the time of writing it has over 100,000 signatures, which means it will be debated in parliament.

A recent study found that restoring forests through planting billions of trees would be by far the cheapest way to tackle climate change and it could be done without encroaching on farmland or urban areas[42].  Such a solution would also have a positive effect on biodiversity, provided the restoration was carefully managed – planting monoculture forests on already biodiverse-rich areas (such as native meadows and grasslands) could inadvertently have an adverse impact on biodiversity.

Not all solutions need to be on such a grand scale; sometimes the little things are just as important. For example, I’ve noticed in my local park this year, the council has planted large areas with wildflower seeds and have let them grow freely over the summer. They’re a joy to look at and they support a wealth of life – each time I walk past I see bumblebees and butterflies and hear the buzz of thousands of insects. The banks require far less maintenance, as there is no need to mow or use herbicides, so it is a win-win.

 A ‘Paris Agreement’ for biodiversity

The closest thing we have to a global agreement on biodiversity is the Convention on Biological Diversity (CBD), which started in 1993. At the tenth Conference of Parties (COP), a revised plan for biodiversity was adopted, which included 20 targets for the period 2011-20, called the ‘Aichi Targets’. The targets are grouped into five themes, all designed to address biodiversity loss.

Performance against the targets has been dismal. Only four of over 50 subgoals have been rated as ‘good progress’ or green and not a single target has been rated as green overall[43]. I’ve read my fair share of RAG (Red-Amber-Green status) reports over the years, but I can’t recall seeing one quite as bad as this one.

It is clear that far stronger global action is needed to address the challenge of biodiversity loss. The world needs the equivalent of a Paris Agreement for Biodiversity.

5. What you can do to help

There are a number of steps that you can take to reduce your impact on nature and mitigate biodiversity loss:

  • Change your diet – Eating less meat is probably the single largest thing you can do to help nature. If you can’t contemplate going vegan or vegetarian, consider one or more meat-free days a week and switching to meats with a lower impact – chicken is far better than beef for example. In addition, try to buy organic produce if you have the means to – organic food is produced without chemical pesticides and so it is far better for insects and soil fertility.
  • Have a conversation about biodiversity – it is important that we escalate the issue of biodiversity loss. Biodiversity loss and climate change should be discussed in unison and join solutions developed.
  • Consider supporting a charity – there are lots of good environmental charities out there. They broadly fall into the categories of direct habitat maintenance and restoration (e.g. Woodland Trust and RSBP), lobbying (e.g. Wilderness Society) and conservation (e.g. WWF).
  • Go wild – If you’re lucky enough to have a garden, consider planting flowers, shrubs and trees that are native to your area. This will act like an island haven for wildlife enabling safe passage through the urban area safely. I’ve lived in apartments ever since moving out of home many years ago, but I still grow flowers and plants on my balcony, which are visited by birds and bees.
  • Read – there are lots of good books on biodiversity. If I had to recommend one, it would actually be a fiction book called “The Overstory” by Richard Powers. It is beautifully written and will almost certainly make you think about trees differently. It won the 2019 Pulitzer Prize for fiction and came close to winning the Man Booker Prize in 2018.
  • Look for sustainable labels – certification schemes are far from perfect, but at the very least, they ensure that certain minimum criteria are met. For paper and wood, FSC certification is the definitive scheme (FSC 100% and FSC recycled are best, while FSC mix is weakest). Rainforest Alliance and UTZ are good for food, coffee and cocoa, while Marine Stewardship Council is the main scheme for sustainable fishing. RSPO promotes sustainable palm oil.

References

[1] “Summary for policymakers of the global assessment report on biodiversity and ecosystem services” (2019) UN Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.

[2] A company called Carbon Engineering has developed a method to extract CO2 from the air using a series of large fans. However, somewhat perversely, the CO2 captured by the pilot plant is being used to help extract more oil from the ground. In order to have a material impact on climate change, the cost per tonne of CO2 captured will need to reduce significantly, and of the extracted CO2 will need to put to better use.

[3] Ceballos et al. (2017) “Population losses and the sixth mass extinction” Proceedings of the National Academy of Sciences, Jul 2017, 114 (30)

[4] Gerasimchuck and Koh (2013) “The EU Biofuel Policy and Palm Oil:Cutting subsidies or cutting rainforest?” International Institute for Sustainable Development

[5] “Life Support Systems” NASA, https://www.nasa.gov/content/life-support-systems

[6] Lafleur, Claude (2010) “Costs of US piloted programs”. The Space Review. Based on $150bn spread over an assumed 20,000 crew days.

[7] Bratman, et al. (2015) “Nature experience reduces rumination and subgenual prefrontal cortex activation” Proceedings of the National Academy of Science.

[8] Hansen, et al. (2017) “Shinrin-Yoku (Forest Bathing) and Nature Therapy: A State-of-the-Art Review”, International Journal of Environmental Research and Public Health

[9] Becket, Derrick (1980) “Brunel’s Britain.” David & Charles.

[10] “The story of Eiji Nakatsu” Japan For Sustainability, JFS Biomimicry Interview Series, Newsletter No.31 (March 2005)

[11] Neergheen-Bhujun, et al. (2017) “Biodiversity, drug discovery, and the future of global health: Introducing the biodiversity to biomedicine consortium, a call to action” Journal of Global Health

[12] Costanza, et al. (1997) “The value of the world’s ecosystem services and natural capital” Nature, 387

[13] Costanza, et al. (2014) “Changes in the global value of ecosystem services” Global Environmental Change, Volume 26, May 2014, Pages 152-158

[14] “Gross domestic product 2018”, World Development Indicators database, World Bank, 1 July 2019

[15] “Will Humans Survive the Sixth Great Extinction?” National Geographic, June 23, 2015.

[16] Grooten, M., et al. (2018) “Living Planet Report – 2018: Aiming Higher.” WWF.

[17] De Vos, et al. (2014) “Estimating the normal background rate of species extinction”, Conservation Biology

[18] Ceballos et al. (2017) “Population losses and the sixth mass extinction” Proceedings of the National Academy of Sciences, Jul 2017, 114 (30)

[19] The IUCN Red List of Threatened Species. Version 2019-2. http://www.iucnredlist.org.

[20] “Summary for policymakers of the global assessment report on biodiversity and ecosystem services” (2019) UN Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.

[21] Sanchez-Bayo, F. and Wyckhuys, K. (2019) “Worldwide decline of the entomofauna: A review of its drivers.” Biological Conservation, 232 8-27.

[22] “‘Death by a thousand cuts’: vast expanse of rainforest lost in 2018” The Guardian, 25 April 2019

[23] “Brazil: huge rise in Amazon destruction under Bolsonaro, figures show” The Guardian, 3 July 2019.

[24] Max Roser and Hannah Ritchie (2019) – “Yields and Land Use in Agriculture”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/yields-and-land-use-in-agriculture’

[25] Clark & Tilman (2017) “Comparative analysis of environmental impacts of agricultural production systems, agricultural input efficiency, and food choice”. Environmental Research Letters, Volume 12, Number 6.

[26] “HS2 rail link”, Woodland Trust

[27] “Two-thirds of the longest rivers no longer flow freely—and it’s harming us”, National Geographic, 8 May 2019

[28] “The state of the world fisheries and aquaculture” (2018) Food and Agriculture Organization of the United Nations

[29] “Gulf of Mexico ‘dead zone’ is the largest ever measured”, National Oceanic and Atmospheric Administration, August 2, 2017.

[30] “Summary for policymakers of the global assessment report on biodiversity and ecosystem services” (2019) UN Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.

[31] Cane toads were referenced in The Simpsons episode “Bart vs. Australia”.

[32] “Killing off the cane toad” (2006), Institute of Molecular Bioscience, University of Queensland.

[33] Sejian V. et al. (2015) “Global Warming: Role of Livestock”. Chapter in: Sejian V., et al. “Climate Change Impact on Livestock: Adaptation and Mitigation”. Springer, New Delhi (2015)”

[34] Willet, et al. (2019) “Food in the Anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems”, The Lancet, 393: 447-92.

[35] “Feeding the Problem: the dangerous intensification of animal farming in Europe” (2019) Greenpeace European Unit.

[36] Sumaila, et al. (2016) “Global fisheries subsidies: An updated estimate” Marine Policy, Volume 69

[37] In practice, as not all global subsides are equal, so it is possible that import tariffs or quotas would be required to avoid foreign producers flooding the market and pushing prices back down.

[38] “Global food losses and food waste – Extent, causes and prevention”(2011) Food and Agricultural Organisation of United Nations.

[39] “Rare Asian black bear spotted in Korean DMZ” The Japan Times, 11 May 2019.

[40] “Rewild a quarter of UK to fight climate crisis, campaigners urge”, The Guardian, 21 May 2019.

[41] “A natural solution to the climate disaster” The Guardian, 3 April 2019

[42] Bastin, J., et al. “The global tree restoration potential”, Science, 5 July 2019, Vol. 365, Issue 6448

[43] “Summary for policymakers of the global assessment report on biodiversity and ecosystem services” (2019) UN Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.