From about 1550 to 1850, a global cold snap called the Little Ice Age supersized glaciers throughout the Arctic. On Canada’s Ellesmere Island, Teardrop Glacier extended its frozen tongue across the landscape and swallowed a small tuft of moss.
Thanks to this latest exploit, evolutionary biologist Catherine La Farge arrived centuries later at Teardrop’s melting edge to find the tuft of the species Aulacomnium turgidum finally free from its icy entombment. The moss was faded and torn but sported a verdant hue – a possible sign of life.
Climate change stories often highlight the teetering fragility of Earth’s ecological system. The picture grew even more dire when a United Nations report said that 1 million of our planet’s plant and animal species face the specter of extinction.
But for a few exceptional species, thawing ice caps and permafrost are starting to reveal another narrative – one of astonishing biological resilience.
Researchers in a warming Arctic are discovering organisms, frozen and presumed dead for millennia, that can bear life anew. These ice age zombies range from simple bacteria to multicellular animals, and their endurance is prompting scientists to revise their understanding of what it means to survive.
In 2009, her team was scouring Teardrop’s margin to collect blackened plant matter spit out by the shrinking glacier. Their goal was to document the vegetation that long ago formed the base of the island’s ecosystem.
“The material had always been considered dead. But by seeing green tissue, “I thought, ‘Well, that’s pretty unusual’,” La Farge said about the centuries-old moss tufts she found.
She brought dozens of these curious samples back to Edmonton, lavishing them with nutrient-rich soils in a bright, warm laboratory. Almost a third of the samples burst forth with new shoots and leaves.
“We were pretty blown away,” La Farge said. The moss showed few ill effects of its multi-centennial deep-freeze.
It’s not easy to survive being frozen solid. Jagged ice crystals can shred cell membranes and other vital biological machinery. Many plants and animals simply succumb to the cold at winter’s onset, willing their seeds or eggs to spawn a new generation come spring.
Thanks to these adaptations, mosses are more likely than other plants to survive long-term freezing, said Peter Convey, an ecologist with the British Antarctic Survey.
On the heels of La Farge’s Canadian moss revival, Convey’s team announced it had awakened a 1,500-year-old moss buried more than three feet underground in the Antarctic permafrost.
“The permafrost environment is very stable,” said Convey, noting that the perennially frozen soil can insulate the moss from surface-level stresses, such as annual freeze-thaw cycles or DNA-damaging radiation.
The regrowth of centuries-old mosses suggests that glaciers and permafrost are not merely graveyards for multicellular life, but they could instead help organisms withstand ice ages. And as human-caused warming peels away ice cover in the Arctic and Antarctic, whoever makes it out of the ice alive is poised to dominate the budding polar ecosystems.
But “when something can survive in situ,” said Convey of the moss his team discovered, “that really accelerates the recolonization process.” These mosses can paint a lifeless landscape green almost overnight, paving the way for other organisms to arrive and establish.
While the elderly mosses discovered by La Farge and Convey are remarkable, the clique of ice age survivors extends well beyond this one group of plants.
Tatiana Vishnivetskaya has studied ancient microbes long enough to make the extreme feel routine. A microbiologist at the University of Tennessee, Vishnivetskaya drills deep into the Siberian permafrost to map the web of single-celled organisms that flourished ice ages ago.
She has coaxed million-year-old bacteria back to life on a petri dish. They look “very similar to bacteria you can find in cold environments [today],” she said.
But last year, Vishnivetskaya’s team announced an “accidental finding” – one with a brain and nervous system – that shattered scientists’ understanding of extreme endurance.
As usual, the researchers were seeking singled-celled organisms, the only life-forms thought to be viable after millennia locked in the permafrost. They placed the frozen material on petri dishes in their room-temperature lab and noticed something strange.
Hulking among the puny bacteria and amoebae were long, segmented worms complete with a head at one end and anus at the other – nematodes.
“Of course we were surprised and very excited,” Vishnivetskaya said. Clocking in at a half-millimeter long, the nematodes that wriggled back to life were the most complex creatures Vishnivetskaya – or anyone else – had ever revived after a lengthy deep freeze.
She estimated one nematode to be 41,000 years old – by far the oldest living animal ever discovered. This very worm dwelled in the soil beneath Neanderthals’ feet and had lived to meet modern-day humans in Vishnivetskaya’s high-tech laboratory.
Experts suggested that nematodes are well-equipped to endure millennia locked in permafrost.
“These buggers survive just about everything,” said Gaetan Borgonie, a nematode researcher at Extreme Life Isyensya in Gentbrugge, Belgium, who was not involved in Vishnivetskaya’s study.
He said nematodes are ubiquitous across Earth’s diverse habitats. Borgonie has found teeming communities of nematodes two miles below Earth’s surface, in South African mine shafts with scant oxygen and scalding heat.
When environmental conditions deteriorate, some nematode species can hunker down into a state of suspended animation called the dauer stage – dauer means duration in German – in which they forestall feeding and grow a protective coating that shields them from extreme conditions.
Vishnivetskaya is not sure whether the nematodes her team pulled from the permafrost passed the epochs in dauer stage. But she speculated that nematodes could theoretically survive indefinitely if frozen stably.
“They may last any number of years if their cells stay intact,” she said.
Borgonie agrees. While he conceded that the finding of Pleistocene-aged nematodes was “a huge surprise,” he said “if they survived 41,000 years, I have no idea what the upper limit is.”
He views nematodes’ virtuosic endurance in a cosmic context. “It’s very good news for the solar system,” said Borgonie, who believes these feats of survival may portend life on other planets.
Here on Earth, many species are spiraling toward extinction as humans jumble the global climate. But near the thawing poles, a hardy few organisms are revealing incredible stamina.
It is ecological gospel that some creatures – from birds to butterflies to wildebeest – survive by migrating vast and hazardous distances to find favorable habitat. More recent discoveries hint at a different migratory mode: through time.
After protracted slumber in Earth’s icy fringes, bacteria, moss and nematodes are awakening in a new geologic epoch. And for these paragons of endurance, the weather is just right.
2019 © The Washington Post
This article was originally published by The Washington Post.
Ira Helfand, a medical doctor, is a member of the international steering group of the International Campaign to Abolish Nuclear Weapons, the recipient of the 2017 Nobel Peace Prize. He is also co-president of the International Physicians for the Prevention of Nuclear War, the founding partner organization of ICAN and itself the recipient of the 1985 Nobel Peace Prize. The opinions expressed in this commentary are solely those of the author. View more opinions on CNN.
(CNN)America confronts a long list of critical problems and they all require urgent attention. But among them, two issues stand out: catastrophic climate change and nuclear war are unique in the threat they pose to the very survival of human civilization. The enormity and imminence of these twin existential threats cannot be overstated and how to confront them must be the central issue of any presidential campaign.
SCIENCE ADVANCES 2 August 2017
Eun-Soon Im,1* Jeremy S. Pal,2* Elfatih A. B. Eltahir3†
The risk of human illness and mortality increases in hot and humid weather associated with heat waves. Sherwood and Huber (1) proposed the concept of a human survivability threshold based on wet- bulb temperature (TW). TW is defined as the temperature that an air parcel would attain if cooled at constant pressure by evaporating water within it until saturation. It is a combined measure of temperature [that is, dry-bulb temperature (T)] and humidity (Q) that is always less than or equal to T. High values of TW imply hot and humid conditions and vice versa. The increase in TW reduces the differential between hu- man body skin temperature and the inner temperature of the human body, which reduces the human body’s ability to cool itself (2). Because normal human body temperature is maintained within a very narrow limit of ±1°C (3), disruption of the body’s ability to regulate temperature can immediately impair physical and cognitive functions (4). If ambient air TW exceeds 35°C (typical human body skin temperature under warm conditions), metabolic heat can no longer be dissipated. Human exposure to TW of around 35°C for even a few hours will result in death even for the fittest of humans under shaded, well-ventilated conditions (1). While TW well below 35°C can pose dangerous conditions for most humans, 35°C can be considered an upper limit on human survivability in a natural (not air-conditioned) environment. Here, we consider maximum daily TW values averaged over a 6-hour window (TWmax), which is considered the maximum duration fit humans can survive at 35°C.
“The big challenge is still to deliver emissions reductions at the pace and scale needed, especially in a world where economies are driven by consumption.”
Sonja van Renssen.The inconvenient truth of failed climate policies. Nature Climate Change MAY 2018
Published online: 27 April 2018 https://doi.org/10.1038/s41558-018-0155-4
The climate change analysis was written by a former fossil fuel executive and backed by the former chief of Australia’s military.
Image: Mark Garlick/Science Photos Library via Getty Images
A harrowing scenario analysis of how human civilization might collapse in coming decades due to climate change has been endorsed by a former Australian defense chief and senior royal navy commander.
The analysis, published by the Breakthrough National Centre for Climate Restoration, a think-tank in Melbourne, Australia, describes climate change as “a near- to mid-term existential threat to human civilization” and sets out a plausible scenario of where business-as-usual could lead over the next 30 years.
On our current trajectory, the report warns, “planetary and human systems [are] reaching a ‘point of no return’ by mid-century, in which the prospect of a largely uninhabitable Earth leads to the breakdown of nations and the international order.”
The only way to avoid the risks of this scenario is what the report describes as “akin in scale to the World War II emergency mobilization”—but this time focused on rapidly building out a zero-emissions industrial system to set in train the restoration of a safe climate.
The scenario warns that our current trajectory will likely lock in at least 3 degrees Celsius (C) of global heating, which in turn could trigger further amplifying feedbacks unleashing further warming. This would drive the accelerating collapse of key ecosystems “including coral reef systems, the Amazon rainforest and in the Arctic.”
The results would be devastating. Some one billion people would be forced to attempt to relocate from unlivable conditions, and two billion would face scarcity of water supplies. Agriculture would collapse in the sub-tropics, and food production would suffer dramatically worldwide. The internal cohesion of nation-states like the US and China would unravel.
“Even for 2°C of warming, more than a billion people may need to be relocated and in high-end scenarios, the scale of destruction is beyond our capacity to model with a high likelihood of human civilization coming to an end,” the report notes.
The new policy briefing is written by David Spratt, Breakthrough’s research director and Ian Dunlop, a former senior executive of Royal Dutch Shell who previously chaired the Australian Coal Association.
In the briefing’s foreword, retired Admiral Chris Barrie—Chief of the Australian Defence Force from 1998 to 2002 and former Deputy Chief of the Australian Navy—commends the paper for laying “bare the unvarnished truth about the desperate situation humans, and our planet, are in, painting a disturbing picture of the real possibility that human life on Earth may be on the way to extinction, in the most horrible way.”
Barrie now works for the Climate Change Institute at Australian National University, Canberra.
Spratt told Motherboard that a key reason the risks are not understood is that “much knowledge produced for policymakers is too conservative. Because the risks are now existential, a new approach to climate and security risk assessment is required using scenario analysis.”
Last October, Motherboard reported on scientific evidence that the UN’s summary report for government policymakers on climate change—whose findings were widely recognized as “devastating”—were in fact too optimistic.
While the Breakthrough scenario sets out some of the more ‘high end’ risk possibilities, it is often not possible to meaningfully quantify their probabilities. As a result, the authors emphasize that conventional risk approaches tend to downplay worst-case scenarios despite their plausibility.
Spratt and Dunlop’s 2050 scenario illustrates how easy it could be to end up in an accelerating runaway climate scenario which would lead to a largely uninhabitable planet within just a few decades.
“A high-end 2050 scenario finds a world in social breakdown and outright chaos,” said Spratt. “But a short window of opportunity exists for an emergency, global mobilization of resources, in which the logistical and planning experiences of the national security sector could play a valuable role.”
Update: This story’s headline has been updated to reflect that the paper suggests 2050 is when the analysts suspect widespread global strife will begin.
The debate over whether climate change will end life on Earth, explained.
I decided not to have children when I was in my 30’s, about 15 years ago. It was really a heartbreaking decision, but I did not want to bring a new life into a world that was clearly out of control and destroying it’s own home. The details on climate change were already known, but mostly hidden and not talked about, and certainly not as dire as todays news. My goal was to adopt an older child, but without the support of my partner I did not pursue that plan, and am now childless. I know how hard that choice is, and would like to listen to and support others through their journey. There are so many ways to use my nurturing, caregiving, mothering desires in my life. I’m very happy and content with my decision.
I was long raised by good mother who taught me the value of the world. This is our only world we must honor it. In “Sahih Muslim 79 a” the prophet Muhammad (PBUH) also tells us of our need for knowledge. I have spoken with my husband and we agreed to not be pregnant again until we really do well for this gift: Earth.
I have never felt strongly compelled to have children, but learning about the environmental impact of new humans and also the world that they would have to live in (effects of climate change) pushed me over the edge into a firm NO.
I am an Environmental Systems Scientist, 52 years old, and have been following climate science for a long time (although it´s not my research area). I used to give public talks on climate in Australia and New Zealand, then I went to sleep on the issue – children and every day life took over. It has only been in recent years that I have re-awoken to the likely horrors that await us. Things seem to changing faster now – I think they´ll progress faster than the scientists have predicted, as feedbacks start to kick-in. As I read recently, we have emitted 50% of all emissions in history in the last 30 years! I´ve seen the glaciers melting, the fires, the tornadoes, typhoons and cyclones, the devastated lives, and this is just the beginning. I fear for the future of my children, I imagine them dying with me when climate change decimates our food supply. I despair at the ignorance and willful greed and callous campaigns of the fossil fuel industries to maintain business as usual when they could have been part of the solution, and I´m disgusted at our politicians, who care more about pandering to powerful lobbies than protecting our futures. I love my children they are here, but had I realised how bad things are going to get, what the future brings, I would not have brought them into the world – I will certainly have no more – I had a vasectomy to make certain. I very strongly agree with the goals of BirthStrike, and ExtinctionRebellion and the school strikes – we need change more than ever.
I was planning on having a family in the future, I’m 25 and single and not currently in a position where I would be having children any time soon but I did certainly want to have children in the future.
I had been thinking since 2015 about other factors that effect how/when/if I should ever have children. Other existential risks as well as technological advances that I felt should be taken in to account with the decision.
It was the IPCC report last October that spurred me into realising Climate Change is also an existential risk and I quickly reprioritised and learnt as much as I could up to Christmas.
In a nutshell, the course humanity is currently on is far more dire than I had realised with regards to climate change, on top of all the existential risks I paying attention to prior to October. I know that unless we take action and successfully prevent a number of things taking place, then it is highly probable our species will be extinct before this century ends. I want to contribute to the survival of our species, as well as the countless other animal and plant species at risk. You can’t maintain a civilisation if no more children are born, of course, but right now I need a certain number of things to happen and for history to change course, big time, before I can accept that we have attained future suitable for starting a family in.
I first learned of climate change in the early eighties, when I was in my early 20s. This, combined with the efforts to turn then rural china and india into consumer populations, made it clear that bringing another American in the world would only accelerate planetary systems breakdown, which would then have to be borne by this child. Meanwhile, so many children already in the world need parents. Having children flew in the face of common sense then, and does so even more now.
Humans are having a phenomenally profound negative impact on our earth and little seems to be done to halt and attempt to reverse the the effect of global issues, such as climate change and pollution. Drastic changes are long overdue and urgent political action needs to be taken to bring about social changes to the way in which we live and consume. Global warming must become the driving force behind the decisions that we as individuals make in our daily lives. As a young professional, I am already challenged to fulfill my personal and professional duties to the best of my ability whilst upholding high regards for the environment; subsequently I recognise that parenting would only make this harder. By refraining from bearing children, I will be able to invest more time and energy into making positive lifestyle changes which will reduce my carbon footprint and consumption of manufactured products. Achieving the plastic free and sustainable lifestyle which I aspire towards will be a timely process and one in which I do not, at present feel I could succeed in and achieve whilst raising a family.
Growing up, I always felt aware of the potential of environmental breakdown. For the last 30 years environmental studies have shown that we are heading for an unsustainable or even unsurvivable future on this planet, so it doesn’t make a lot of sense to me to bring new life into this world.
My husband and I spent years trying to decide whether to have children, but ultimately the deciding factor was the uncertainty over climate.
I do not feel like I would be able to ensure that any child I had had a reasonable chance of a good future where they could thrive.
I am 60. My daughter is 30…she isn’t planning on kids…many reasons. Geo-politically & environmentally speaking the world is moving toward an ugly breakdown that the act of bringing children into this world would render cruel and unusual punishment. Abrupt Climate Change is the be all and end all of critical situations the world shares, and if more children are born and not given the tools to adapt (if even possible) our current generation will set up the next generation for unimaginable hardships and horrors.
Observing and continuing to learn about climate issues, other man made ecological issues, political climate and many other problems in the modern world it has become clear to me this isn’t a world I would want to raise children in, there’s too much wrong with it.
This movement makes me sad, but I support the concept. I’ve been at this four decades. My whole life’s work has been about the environment and Gaia. There is still some hope though, but you don’t need kids to be happy in life.
I grew up in South Africa, it was a beautiful childhood but tainted by the apartheid government. Even as a child I was aware of the planet and her fragility.
When climate change first reared her ugly head back in the 80’s I was constantly commenting on changing weather patterns (which no-one else thought was weird), I started to feel internally alarmed.
Then people began talking about the hole in the ozone layer, & climate change suddenly became topical. What alarmed me most was that although everyone was talking about it, no one was doing anything about it.
It’s been that way ever since. We watch in horror as forests burn, species are made extinct, environments destroyed, over fishing, I could go on and on…Our planet is at crisis point. If we keep talking and don’t implement rapid and extreme changes, there will be no future for anyone.
Although I was never one of those young girls who fantasized about getting married and having children, I have recently been pondering the idea now that I’m entering my thirties. But along with my slowly growing interest in creating offspring, my knowledge and awareness of the climate crisis has increased at a much faster rate. I am now comfortable and at peace with my plan to not have children, and I no longer see my reasons as selfish. Instead, I view my choice as more of a self-less one. It is, of course, enjoyable to entertain the idea of having children, especially when you share your life with a partner you love very much. But I think it is unfair to bring a child into the world and place the immense responsibility of dealing with a severely unstable world on them. I have enough anxiety when I think of my future, let alone the future humans will have to deal with over the next 100+ years.
Our world is dying. If carbon emissions globally ended tomorrow, the environment still would not ever completely recover. In my lifetime, we have seen catastrophic loss of species and life globally including ocean dead zones and food desserts. This is the result of an unsustainable way of living, this is the result of human interference with the environment and the mentality of harvesting what was never ours to take. To bring a human being into this world only to live with the consequences of our destruction is the most cruel thing I could bestow on another being. I hope one day the earth can heal in ways we can’t predict but for now, I do all I can. I reject the concepts of property ownership and live minimally and low waste. I have rejected the idea that my life is any more valuable than any other species and work to promote animal rights nationally and globally. We will not change the world unless we drastically and urgently change our understanding of our origin story. That humans were placed on earth not as Masters of all that it holds but guardians and protectors from the harms we have the potential to cause. Change must come now, if not for our natural world, for the sake of the future generations who will call what is left of the planet, home.
I’m a teacher, and see the young coming through, and it scares me! The decline in general health is scary, and the attitude towards the world, breaks my heart. Many of the next generation is more of a parasite than my own, more concerned with consumption and their rights than anything else. This world now is not good enough for my offspring… I wouldn’t wish this future on anyone else, never mind my own child.
The future terrifies me, it terrifies me that one day we won’t have wildlife, our oceans will be full of nothing but plastic and poison, the only nature we will see will be in books. The wonders of the world will disappear amid a caving climate – I don’t want to bring children into that kind of world and I don’t want to add to the pressure on an already breaking environment, since a young age I have researched the detrimental affects humans have had on the planet and that is what first introduced me to the notion of not having children and not bringing them up in a world where the hope of things improving are dwindling.
I think if I were to have a child and they were to turn 18, what will life be like for them? Current governments staying in power is bad enough, corporations running everything even worse but worse of all is climate change and it’s ignored by corporations, government, media and by so many people. So, I think if nothing huge is changed, my child at 18 will never be able to see so many animals in the wild such as elephants, rhinos etc, my child will be constantly hearing of food, water, land shortages on the news, wars being fought over these things. The fact we moaned about 1.5million people coming to Europe in the last few yrs but will face 10’s of millions heading to Europe in the next decades purely due to climate change and how this will affect jobs, food, and literally everything we take for granted. Disasters constantly all over the world. Places like Miami, New York and many other coastal places, Islands all over the world flooded daily or even gone. I’m 37 and will witness all this and I’m terrified of my own future as I still can’t even afford to move out my parents and get stable work, how on earth is my child suppose to survive in the future we have destined for them
I am on Birthstrike because the number one parental responsibility is to keep your child safe, and therefore in a world like this, to fulfill your parental responsibilities ironically means not having your own children, but to strive to save ALL of life instead and to enable future generations to be able to be born safely in the future. When scientists predict the last harvest in the UK to be in roughly 60 years, I’m terrified for my generation’s life, let alone future generations. There are countless people that feel this way, but #BirthStrike is the first platform to give us a voice.
My partner and I both have decided against having biological children due 100% to issues involving sustainability on a local and global scale. If this issue were resolved we would both want to be parents.
When I was a child the mere mention of climate change would cause me to have a panic attack. The idea that the world could go through such a catastrophe, or that I would live to see it happen, was too much for me to handle. It fostered mental illnesses such as anxiety and depression. I went through periods of denial because that’s the only way I knew how to deal with it.
Now I’ve come to terms with the reality that climate change is real, and knowing how that anxiety robbed me of my childhood and caused me so much suffering, I can’t bring an innocent child into the world knowing that they will have it even worse than I did, and that they will not even begin to have a full life.
It is not only climate breakdown for me, it is also the whole catastrophe of the capitalist market which at every turn creates less opportunities for a healthy balanced family life
The driving force behind global challenges, including climate change, is our current economic models do not account very well for the externalities they cause.
Secondly, our political and economic systems, well at least most, are predicated on growth as a key function of their stability.
Third, the hegemony of the day has set the two final pavings stones of philosophy between two books. One is, Huntington’s a clash of civilizations and the other is Fukyama’s The End of History and The Last Man. This means the past and the future are cut off and we are driving around in a cul-de-sac of capitalism and conflict.
Combined, the orthodoxy has entrenched itself to protect a way of life that is not tenable on this planet.
There are alternatives, for example Kate Raworth brings up doughnut economics which adds many important concepts. For example, that the household should be recognized as part of the real economy and that the cost of the externalities should be calculated into price. Of course, this is transitional thinking needed to move forward. Moving all the way, would cause those living over their personally allotted ecological carrying capacity to be severally taxed to the point where they could not…we have a long way to go. “
I created the website dietdissonance.com to create awareness of the diet and why/how people decide to follow a plant-based lifestyle. While the information on that website is focused on dietary choices, it is thoroughly researched and I’ve included a Facts Page where people can find links to the research available on the covered topics (http://dietdissonance.com/facts_regular.html) It was during this research phase of building this website that I really began to feel like humanity was too stubborn and so strongly driven by immediate gratification, that any sizable change to our health or the health of the planet was unlikely to take place. Even at the risk of death and disease of ourselves and the world around us, people continue to eat meat. I’m not sure how to convince others to change their ways, but I’d like to figure it out before it’s too late.
I’ve always been anxious about my biological footprint, and became vegan five years ago in an effort to decrease my global impact. Once vegan, I found it easier to pursue other areas of environmental impact, and have tried to follow a zero waste lifestyle as well as participating in activism/outreach and my local DSA. At this point, for me, I really enjoy zero waste and veganism, but every time I read/hear about the environment, or when there is a big storm, or our government (or other governments) do things that are in direct disregard for the natural world/our future on this planet, I feel really lost. This “lost” feeling is also a feeling of emptiness. It is very depressing to feel powerless, to feel like the people in your life (and the ones who aren’t) somehow don’t care at all about the future that we are all creating together. I don’t understand how others are able to just ignore or disregard the facts, especially now that we are experiencing more dangerous natural storms.
I’ve been undecided whether or not to have children. But now this world definitely does not seem to be a a place to bring a little life into. Also doing that would just add to the draining of our planetary resources.
London (CNN)Climate change is rapidly changing the environment we live in. But how far would you be willing to go to help save the planet?
‘Inheriting a world worse than ours’
More children, more emissions
Consumption, not population?
The opportunity cost of a child
Creating political action
- Our planet is in the middle of a mass extinction — the sixth time in Earth’s history that animal and plant species are disappearing in enormous numbers.
- Amphibians, particularly frogs, are among the hardest hit by this extinction crisis, as are insects and reptiles.
- At least 2,000 species of amphibian are in danger of extinction, according to a recent study. A report from the United Nations confirmed that 40% of amphibian species are threatened.
- Here are photos of 15 endangered frogs, geckos, and snakes that might soon disappear.
- Visit Business Insider’s homepage for more stories.
Human activity has killed off 680 mammal, bird, reptile, amphibian, and fish species since the 1500s. As much as half of the total number of animal individuals that once shared the planet with us are already gone.
That death toll is likely to rise dramatically over the next decades.
A recent report from the United Nations found that between 500,000 and 1 million plant and animals species face imminent extinction. At least 10% of insect species and more than 33% of all marine mammals and reef-forming coral are threatened, it found.
But one group is expected to suffer most of all: Amphibians. An estimated 40% of amphibian species face extinction, according to the UN report. A study published in the journal Current Biology estimated that at least 2,000 amphibian species are in danger of extinction.
This group includes frogs, toads, salamanders, and newts.
In the past 50 years, more than 500 amphibian species have experienced population declines worldwide, and 90 of them have gone extinct, due to a deadly fungal disease called chytridiomycosis (or chytrid fungus), which corrodes frog flesh.
“These are images from the NOAA website of the US blackout in 2003,” he said, pulling up a nighttime satellite picture of the glowing northeastern megalopolis, megawatts afire under the cold dark of space. “This is 20 hours before the blackout. You can see Long Island and New York City.”
Erwin is one of the world’s experts on the End-Permian mass extinction, an unthinkable volcanic nightmare that nearly ended life on earth 252 million years ago. He proposed that earth’s great mass extinctions might unfold like these power grid failures: most of the losses may come, not from the initial shock—software glitches in the case of power grid failures, and asteroids and volcanoes in the case of ancient mass extinctions—but from the secondary cascade of failures that follow. These are devastating chain reactions that no one understands. Erwin thinks that most mass extinctions in earth’s history—global die-offs that killed the majority of animal life on earth—ultimately resulted, not from external shocks, but from the internal dynamics of food webs that faltered and failed catastrophically in unexpected ways, just as the darkening eastern seaboard did in 2003.
The oceans have endured a similar transformation in only the past few decades as the industrial might developed during World War II has been trained on the seas. Each year fishing trawlers plow an area of seafloor twice the size of the continental United States, obliterating the benthos. Gardens of corals and sponges hosting colorful sea life are reduced to furrowed, lifeless plains. What these trawlers have to show for all this destruction is the removal of up to 90 percent of all large ocean predators since 1950, including familiar staples of the dinner plate like cod, halibut, grouper, tuna, swordfish, marlin, and sharks. As just one slice of that devastation, 270,000 sharks are killed every single day, mostly for their tasteless fins, which end up as status symbol garnishes in the bowls of Chinese corporate power lunches. And today, even as fishing pressure is escalating, even as the number of fishing boats increases, even as industrial trawlers abandon their exhausted traditional fishing grounds to chase down ever more remote fish stocks with ever more sophisticated fish-finding technology, global fish catch is flatlining.
Erwin says no. He thinks it’s junk science.
“Many of those making facile comparisons between the current situation and past mass extinctions don’t have a clue about the difference in the nature of the data, much less how truly awful the mass extinctions recorded in the marine fossil record actually were,” he wrote me in an email. “It is absolutely critical to recognize that I am NOT claiming that humans haven’t done great damage to marine and terrestrial [ecosystems], nor that many extinctions have not occurred and more will certainly occur in the near future. But I do think that as scientists we have a responsibility to be accurate about such comparisons.”
I had a chance to sit down with Erwin after his talk at the annual geology conference. My first question—about a rumor I had heard from one of his colleagues that Erwin had served as a sort of mass extinction consultant to Cormac McCarthy while the notoriously secretive author was constructing the post-apocalyptic world of The Road—Erwin coyly evaded. But on the speculative sixth mass extinction, he was more forthcoming.
This is because by the time a mass extinction starts, the world would already be over.
“So if we really are in the middle of a mass extinction,” I started, “it wouldn’t be a matter of saving tigers and elephants—”
“Right, you probably have to worry about saving coyotes and rats.
“It’s a network collapse problem,” he said. “Just like power grids. Network dynamics research has been getting a ton of money from DARPA [Defense Advanced Research Projects Agency]. They’re all physicists studying it, who don’t care about power grids or ecosystems, they care about math. So the secret about power grids is that nobody actually knows how they work. And it’s exactly the same problem you have in ecosystems.
“I think that if we keep things up long enough, we’ll get to a mass extinction, but we’re not in a mass extinction yet, and I think that’s an optimistic discovery because that means we actually have time to avoid Armageddon,” he said.
Erwin’s other point, that the magnitude of the Big Five mass extinctions in earth’s past dwarfs humanity’s destruction thus far, is a subtle one. He’s not trying to downplay the tremendous destruction wrought by humans, but reminding us that claims about mass extinctions are inevitably claims about paleontology and the fossil record.
“So there are estimates of what the standing crop of passenger pigeons was in the 19th century,” said Erwin. “It’s like 5 billion. They would black out the sky.”
Passenger pigeons all but serve as the mascot of the “sixth mass extinction,” their extirpation an ecological tragedy on a massive scale, and proof that humans are a geologically destructive force to be reckoned with.
“So then you ask: in a non-archaeological context, how many fossil passenger pigeons are there? How many records are there of fossil passenger pigeons?”
“Not many?” I offered. “Two,” he said. “So here’s an incredibly abundant bird that we wiped out. But if you look in the fossil record, you wouldn’t even know that they were there.”
Erwin likes to recall a talk he once went to by an ecologist who had documented the troubling losses he had seen over his career in high-altitude rainforests.
The fossil record is incredibly incomplete. One rough estimate holds that we’ve only ever found a tantalizing 0.01 percent of all the species that have ever existed. Most of the animals in the fossil record are marine invertebrates, like brachiopods and bivalves, of the sort that are both geologically widespread and durably skeletonized. In fact, though this book (for narrative purposes) has mostly focused on the charismatic animals taken out by mass extinctions, the only reason we know about mass extinctions in the first place is from the record of this incredibly abundant, durable, and diverse world of marine invertebrates, not the big, charismatic, and rare stuff like dinosaurs.
“So you can ask, ‘Okay, well, how many geographically widespread, abundant, durably skeletonized marine taxa have gone extinct thus far?’ And the answer is, pretty close to zero,” Erwin pointed out. In fact, of the best-assessed groups of modern animals—like stony corals, amphibians, birds and mammals—somewhere between 0 and 1 percent of species have gone extinct in recent human history. By comparison, the hellscape of End-Permian mass extinction claimed upwards of 90 percent of all species on earth.
When mass extinctions hit, they don’t just take out big charismatic megafauna, like elephants, or niche ecosystems, like cloud forests. They take out hardy and ubiquitous organisms as well—things like clams and plants and insects. This is incredibly hard to do. But once you go over the edge and flip into mass extinction mode, nothing is safe. Mass extinctions kill almost everything on the planet.
While Erwin’s argument that a mass extinction is not yet under way might seem to get humanity off the hook—an invitation to plunder the earth further, since it can seemingly take the beating (the planet has certainly seen worse)—it’s actually a subtler and possibly far scarier argument.
This is where the ecosystem’s nonlinear responses, or tipping points, come in. Inching up to mass extinction might be a little like inching up to the event horizon of a black hole—once you go over a certain line, a line that perhaps doesn’t even appear all that remarkable, all is lost.
“So,” I said, “it might be that we sort of bump along where everything seems okay and then . . .”
“Yeah, everything’s fine until it’s not,” said Erwin. “And then everything goes to hell.”
Or put another way, mass extinctions may unfold the same way that a dissolute character in Hemingway’s The Sun Also Rises explains that bankruptcies do: “Two ways. Gradually and then suddenly.”
“The only hope we have in the future,” Erwin said, “is if we’re not in a mass extinction event.”
This article has been adapted from Peter Brannen’s new book, The Ends of the World.