Rapid global warming caused the largest extinction event in the Earth’s history, which wiped out the vast majority of marine and terrestrial animals on the planet, scientists have found.
The mass extinction, known as the “great dying”, occurred around 252m years ago and marked the end of the Permian geologic period. The study of sediments and fossilized creatures show the event was the single greatest calamity ever to befall life on Earth, eclipsing even the extinction of the dinosaurs 65m years ago.
Up to 96% of all marine species perished while more than two-thirds of terrestrial species disappeared. The cataclysm was so severe it wiped out most of the planet’s trees, insects, plants, lizards and even microbes.
Scientists have theorized causes for the extinction, such as a giant asteroid impact. But US researchers now say they have pinpointed the demise of marine life to a spike in Earth’s temperatures, warning that present-day global warming will also have severe ramifications for life on the planet. [Continue reading…]
Rapid warming caused largest extinction event ever on Earth, report says
Portrait of the Earth at the threshold of climate catastrophe
On Sunday morning hundreds of politicians, government officials and scientists will gather in the grandeur of the International Congress Centre in Katowice, Poland. It will be a familiar experience for many. For 24 years the annual UN climate conference has served up a reliable diet of rhetoric, backroom talks and dramatic last-minute deals aimed at halting global warming.
But this year’s will be a grimmer affair – by far. As recent reports have made clear, the world may no longer be hovering at the edge of destruction but has probably staggered beyond a crucial point of no return. Climate catastrophe is now looking inevitable. We have simply left it too late to hold rising global temperatures to under 1.5C and so prevent a future of drowned coasts, ruined coral reefs, spreading deserts and melted glaciers.
One example was provided last week by a UN report that revealed attempts to ensure fossil fuel emissions peak by 2020 will fail. Indeed the target will not even be reached by 2030. Another, by the World Meteorological Organization, said the past four years had been the warmest on record and warned that global temperatures could easily rise by 3-5C by 2100, well above that sought-after goal of 1.5C. The UK will not be exempt either. The Met Office said summer temperatures could now be 5.4C hotter by 2070.
At the same time, prospects of reaching global deals to halt emissions have been weakened by the spread of rightwing populism. Not much to smile about in Katowice.
Nor will the planet’s woes end in 2100. Although most discussions use the year as a convenient cut-off point for describing Earth’s likely fate, the changes we have already triggered will last well beyond that date, said Svetlana Jevrejeva, at the National Oceanography Centre, Liverpool. She has studied sea-level rises that will be triggered by melting ice sheets and expanding warm seawater in a world 3-5C hotter than it was in pre-industrial times, and concludes these could reach 0.74 to 1.8 metres by 2100. This would be enough to deluge Pacific and Indian Ocean island states and displace millions from Miami, Guangzhou, Mumbai and other low-lying cities. The total cost to the planet could top £11trillion.
Even then the seas will not stop rising, Jevrejeva added. “They will continue to climb for centuries even after greenhouse-gas levels have been stabilised. We could experience the highest-ever global sea-level rise in the history of human civilisation.”
Vast tracts of prime real estate will be destroyed – at a time when land will be needed with unprecedented desperation. Earth’s population stands at seven billion today and is predicted to rise to nine billion by 2050 and settle at over 11 billion by 2100 – when climate change will have wrecked major ecosystems and turned farmlands to dust bowls.
Unfortunately many experts believe Earth’s population will actually peak well beyond 11 billion. “It could reach 15 billion,” said Sarah Harper, of Oxford’s Institute of Population Ageing. “All sorts of factors suggest women, particularly in sub-Saharan Africa, will still want to have relatively high numbers of children and this might keep the world’s population approaching 15 billion rather than 12 billion.”
The world will have double its present numbers – but with hugely reduced areas of fertile land to provide food. We will be living in a shrunken, scorched planet bursting with human beings. Somaliland gives a grim vision of this future.
In the past few years climate change has killed 70% of its livestock and forced tens of thousands of families to flee from its scorched interior to live in refugee camps. “You can touch it, the climate change, in Somaliland. It is real. It is here,” the country’s environment minister, Shukri Ismail Bandare, said in the Financial Times last week.
Sudan and Kenya are also victims of a drought that has dried the Horn of Africa faster than at any other time in the past 2,000 years. Similarly, in Vietnam, thousands a year are abandoning the once fertile Mekong Delta as rising seawater pollutes paddy fields. By 2050, the World Bank says more than 140 million will become climate refugees.
It will be bad for humans, but catastrophic for Earth’s other inhabitants. Arctic ice loss threatens polar bears, droughts imperil monarch butterflies, and koala habitats are being destroyed by bush fires. In all, about a sixth of all species now face extinction, say scientists, although in the end no creature or plant will be safe. “Even the most resilient species will inevitably fall victim as extreme stresses drive ecosystems to collapse,” said Giovanni Strona of Europe’s Joint Research Centre in a report last week on climate change. [Continue reading…]
The insect apocalypse is here. What does it mean for the rest of life on Earth?
Sune Boye Riis was on a bike ride with his youngest son, enjoying the sun slanting over the fields and woodlands near their home north of Copenhagen, when it suddenly occurred to him that something about the experience was amiss. Specifically, something was missing.
It was summer. He was out in the country, moving fast. But strangely, he wasn’t eating any bugs.
For a moment, Riis was transported to his childhood on the Danish island of Lolland, in the Baltic Sea. Back then, summer bike rides meant closing his mouth to cruise through thick clouds of insects, but inevitably he swallowed some anyway. When his parents took him driving, he remembered, the car’s windshield was frequently so smeared with insect carcasses that you almost couldn’t see through it. But all that seemed distant now. He couldn’t recall the last time he needed to wash bugs from his windshield; he even wondered, vaguely, whether car manufacturers had invented some fancy new coating to keep off insects. But this absence, he now realized with some alarm, seemed to be all around him. Where had all those insects gone? And when? And why hadn’t he noticed?
Riis watched his son, flying through the beautiful day, not eating bugs, and was struck by the melancholy thought that his son’s childhood would lack this particular bug-eating experience of his own. It was, he granted, an odd thing to feel nostalgic about. But he couldn’t shake a feeling of loss. “I guess it’s pretty human to think that everything was better when you were a kid,” he said. “Maybe I didn’t like it when I was on my bike and I ate all the bugs, but looking back on it, I think it’s something everybody should experience.”
I met Riis, a lanky high school science and math teacher, on a hot day in June. He was anxious about not having yet written his address for the school’s graduation ceremony that evening, but first, he had a job to do. From his garage, he retrieved a large insect net, drove to a nearby intersection and stopped to strap the net to the car’s roof. Made of white mesh, the net ran the length of his car and was held up by a tent pole at the front, tapering to a small, removable bag in back. Drivers whizzing past twisted their heads to stare. Riis eyed his parking spot nervously as he adjusted the straps of the contraption. “This is not 100 percent legal,” he said, “but I guess, for the sake of science.”
Riis had not been able to stop thinking about the missing bugs. The more he learned, the more his nostalgia gave way to worry. Insects are the vital pollinators and recyclers of ecosystems and the base of food webs everywhere. Riis was not alone in noticing their decline. In the United States, scientists recently found the population of monarch butterflies fell by 90 percent in the last 20 years, a loss of 900 million individuals; the rusty-patched bumblebee, which once lived in 28 states, dropped by 87 percent over the same period. With other, less-studied insect species, one butterfly researcher told me, “all we can do is wave our arms and say, ‘It’s not here anymore!’ ” Still, the most disquieting thing wasn’t the disappearance of certain species of insects; it was the deeper worry, shared by Riis and many others, that a whole insect world might be quietly going missing, a loss of abundance that could alter the planet in unknowable ways. “We notice the losses,” says David Wagner, an entomologist at the University of Connecticut. “It’s the diminishment that we don’t see.”
Because insects are legion, inconspicuous and hard to meaningfully track, the fear that there might be far fewer than before was more felt than documented. People noticed it by canals or in backyards or under streetlights at night — familiar places that had become unfamiliarly empty. The feeling was so common that entomologists developed a shorthand for it, named for the way many people first began to notice that they weren’t seeing as many bugs. They called it the windshield phenomenon. [Continue reading…]
The health of an ecosystem (including your home) depends on its biodiversity
Rob Dunn invites us on a safari in pursuit of the wildlife teeming on our bodies and in every corner of our homes. For him, the creatures that sprawl in the human navel and under the bathroom shower head elicit the kind of wonder most of us would feel only on seeing the denizens of Tanzania’s Ngorongoro Crater or the Great Barrier Reef off Australia. Dunn is more than an informed and entertaining commentator, a David Attenborough of domestic biodiversity. He is a scientist whose research group at North Carolina State University in Raleigh made many of the discoveries described in his fascinating and illuminating book, Never Home Alone.
Dunn and his colleagues have used the concepts and techniques of community ecology to tease apart the functioning of a mostly ignored ecosystem: the human home. Their research enriches our understanding of ecosystem function, and — more grippingly — gives us insight into how our interactions with living things in the domestic habitat affect our health and well-being. The book is structured around sub-habitats in our homes — our bodies, rooms, water supply, pets and food. It considers an awesome range of organisms, from the rich fungal flora on bakers’ hands to the diversity of fly larvae in our drains.
We discover that warm, moist shower heads are ideal for the growth of biofilms containing trillions of bacteria, including Mycobacterium species that are harmful to human health. Dunn and his colleagues invited thousands of volunteers globally to send in samples from their bathrooms. The researchers are finding, for instance, that the more a water supply is treated with chemicals designed to kill microbes, the greater the abundance of pathogenic strains of mycobacteria. We also learn that the numbers of plant and butterfly species in our gardens are correlated with the robustness of the community of microbes on our skin; that some German cockroaches have evolved to perceive glucose as bitter, thus avoiding poisoned bait; and that dogs can give us both heartworm and a top-up of beneficial bacteria from their microbiomes.
The message of Never Home Alone is clear. The health of an ecosystem depends on its biodiversity: this is as true of our homes as of a mangrove swamp. Two factors, notes Dunn, are important. Simply by chance, a home containing more species is more likely to include organisms (especially microbes) that are vital in sparking our immune systems into life. And an ecosystem with niches fully occupied by diverse species is likely to be resilient and resistant to invasion by pests and pathogens. [Continue reading…]
Stop biodiversity loss or we could face our own extinction, warns UN
The world must thrash out a new deal for nature in the next two years or humanity could be the first species to document our own extinction, warns the United Nation’s biodiversity chief.
Ahead of a key international conference to discuss the collapse of ecosystems, Cristiana Pașca Palmer said people in all countries need to put pressure on their governments to draw up ambitious global targets by 2020 to protect the insects, birds, plants and mammals that are vital for global food production, clean water and carbon sequestration.
“The loss of biodiversity is a silent killer,” she told the Guardian. “It’s different from climate change, where people feel the impact in everyday life. With biodiversity, it is not so clear but by the time you feel what is happening, it may be too late.”
Pașca Palmer is executive director of the UN Convention on Biological Diversity – the world body responsible for maintaining the natural life support systems on which humanity depends.
Its 196 member states will meet in Sharm el Sheikh, Egypt, this month to start discussions on a new framework for managing the world’s ecosystems and wildlife. This will kick off two years of frenetic negotiations, which Pașca Palmer hopes will culminate in an ambitious new global deal at the next conference in Beijing in 2020. [Continue reading…]
Humanity’s preoccupation with short-term gains threatens the future of life on Earth
We are experiencing the sixth great extinction. The most recent report from WWF describes the situation as critical – in the last 40 years, we have lost some 60% of all animal and plant species on Earth.
We are poisoning the soil through large-scale industrial agriculture. Invasive species are choking out native animal and plant life in many places. Carbon dioxide is released into the atmosphere by our reliance on fossil fuels, destruction of the rain forests and pollution of the ocean. Increase of demand for meat not only involves horrible cruelty to billions of animals in factory farms, but huge areas of wild habitats are destroyed to grow crops for animal feed.
So much fossil fuel is required to take grain to animals, animals to slaughter, meat to table – and during digestion these animals are producing methane – an even more virulent gas than carbon dioxide. And their waste along with other industrial agricultural runoff is polluting soil and rivers sometimes causing toxic algae blooms over large areas of ocean.
Climate change is a very real threat as spelled out in the latest UN report, as these greenhouse gases, trapping the heat of the sun, are causing the melting of polar ice, rising sea levels, more frequent and more intense storms, flooding and droughts. In some places agricultural yields are decreasing, fuelling human displacement and conflict. How come the most intellectual creature to ever walk Earth is destroying its only home?
Because many policymakers and corporations – and we as individuals – tend to make a decision based on “How will this affect me now, affect the next shareholders meeting, the next political campaign?” rather than “How will this affect future generations?” Mother nature is being destroyed at an ever-faster rate for the sake of short term gain. This, along with our horrifying population growth, poverty – causing people to destroy the environment simply to try to make a living, and the unsustainable lifestyles of the rest of us who have way more than we need, is the root cause of all the planet’s woes. [Continue reading…]
Call to protect dwindling wilderness ‘before it disappears forever’
New, highly detailed maps now reveal the state of the world’s wilderness, both on land and at sea, and the picture looks bleak.
In a series of recent studies, a group of researchers led by ecologist James Watson of the Wildlife Conservation Society and Australia’s University of Queensland analyzed the surface of Earth for significant human activity, such as roads and railways, pastures and farmland, and population centers, at a resolution of 1 square kilometer (0.4 square miles). In the oceans, they looked at fishing efforts as well as fertilizer effluent and shipping lanes.
The results are staggering, as summarized Oct. 31 in the journal Nature: Just 13 percent of the world’s oceans lack signs of human activity. And the figures on land aren’t much higher: not counting Antarctica, just 23 percent of terrestrial wilderness remains. But hidden in what Watson called a “horror story” for untouched places is the potential to save what’s left and, with it, life on Earth.
“Science is clearly showing that large intact places are the best low-hanging fruit that we should go and conserve,” Watson told Mongabay.
Early on in the research, a 2016 study comparing those changes with the pace of population and economic growth indicated that we weren’t losing wilderness as quickly as might be expected. Those “encouraging” results suggested that, as a species, we humans were using resources more efficiently, the researchers said.
But as the scientists dug deeper into the data, producing maps that looked at how well parks and reserves safeguard biodiversity and wild spaces from human impacts and the extent of humanity’s reach in the world’s oceans, for example, Watson said the story that emerged was “how little is left.” [Continue reading…]
Humanity is destroying life on Earth
Humanity has wiped out 60% of mammals, birds, fish and reptiles since 1970, leading the world’s foremost experts to warn that the annihilation of wildlife is now an emergency that threatens civilisation.
The new estimate of the massacre of wildlife is made in a major report produced by WWF and involving 59 scientists from across the globe. It finds that the vast and growing consumption of food and resources by the global population is destroying the web of life, billions of years in the making, upon which human society ultimately depends for clean air, water and everything else.
“We are sleepwalking towards the edge of a cliff” said Mike Barrett, executive director of science and conservation at WWF. “If there was a 60% decline in the human population, that would be equivalent to emptying North America, South America, Africa, Europe, China and Oceania. That is the scale of what we have done.”
“This is far more than just being about losing the wonders of nature, desperately sad though that is,” he said. “This is actually now jeopardising the future of people. Nature is not a ‘nice to have’ – it is our life-support system.” [Continue reading…]
The Chinese government, reversing a 25-year ban, announced on Monday that it would allow the use of rhinoceros horns and tiger bones in medicine, a move that environmentalists described as a significant setback for efforts to protect the animals from extinction.
The State Council, China’s cabinet, said in a policy directive that it would legalize the use of rhino horns and tiger bones for “medical research or in healing,” but only by certified hospitals and doctors, and only from rhinos and tigers raised in captivity, excluding zoo animals.
Still, environmentalists said the decision would likely help fuel a black market for wild rhino and tiger parts, which are revered in traditional Chinese medicine for supposed healing powers, and could lead to increased poaching of the fewer than 30,000 rhinos and 3,900 tigers still in the wild. [Continue reading…]
Humanity is ‘cutting down the tree of life’, warn scientists
Humanity’s ongoing annihilation of wildlife is cutting down the tree of life, including the branch we are sitting on, according to a stark new analysis.
More than 300 different mammal species have been eradicated by human activities. The new research calculates the total unique evolutionary history that has been lost as a result at a startling 2.5bn years.
Furthermore, even if the destruction of wild areas, poaching and pollution were ended within 50 years and extinction rates fell back to natural levels, it would still take 5-7 million years for the natural world to recover.
Many scientists think a sixth mass extinction of life on Earth has begun, propelled by human destruction of wildlife, and 83% of wild mammals have already gone. The new work puts this in the context of the evolution and extinction of species that occurred for billions of years before modern humans arrived.
“We are doing something that will last millions of years beyond us,” said Matt Davis at Aarhus University in Denmark, who led the new research. “It shows the severity of what we are in right now. We’re entering what could be an extinction on the scale of what killed the dinosaurs.
“That is pretty scary. We are starting to cut down the whole tree [of life], including the branch we are sitting on right now.” Ecosystems around the world have already been significantly affected by the extermination of big animals such as mammoths, he said. [Continue reading…]
‘Hyperalarming’ study shows massive insect loss
Insects around the world are in a crisis, according to a small but growing number of long-term studies showing dramatic declines in invertebrate populations. A new report suggests that the problem is more widespread than scientists realized. Huge numbers of bugs have been lost in a pristine national forest in Puerto Rico, the study found, and the forest’s insect-eating animals have gone missing, too.
In 2014, an international team of biologists estimated that, in the past 35 years, the abundance of invertebrates such as beetles and bees had decreased by 45 percent. In places where long-term insect data are available, mainly in Europe, insect numbers are plummeting. A study last year showed a 76 percent decrease in flying insects in the past few decades in German nature preserves.
The latest report, published Monday in the Proceedings of the National Academy of Sciences, shows that this startling loss of insect abundance extends to the Americas. The study’s authors implicate climate change in the loss of tropical invertebrates.
“This study in PNAS is a real wake-up call — a clarion call — that the phenomenon could be much, much bigger, and across many more ecosystems,” said David Wagner, an expert in invertebrate conservation at the University of Connecticut who was not involved with this research. He added: “This is one of the most disturbing articles I have ever read.” [Continue reading…]