Tag Archives: extinction

Scrambled DNA of extinct rat suggests there’s no hope to resurrect the woolly mammoth

The Christmas Island rat. Credit: Public Domain.

In recent times, some high-profile geneticists gained a lot of publicity when they said they’re working to resurrect the wooly mammoth, an iconic megafauna species that went extinct during the last ice age, some 10,000 years ago. The whole thing gave off massive Jurassic Park vibes, and given its ambitious scope, the mission was widely picked up by the media. After all, is there anything that science can’t do?

The problem is that, in reality, this challenge could prove virtually impossible. Richard Feynman once said ‘science is imagination in a straitjacket,’ alluding to the fact that wild ideas, by themselves, are not enough to make a breakthrough. For imagination to become reality, it needs to be materialized within physical constraints — and a new study suggests there’s a hard floor when it comes to reconstructing the genetic material of long-extinct species.

Extinct species may be dead for good

Thomas Gilbert at the University of Copenhagen in Denmark set out to probe the limits of CRISPR — a powerful tool for editing genomes that allows researchers to easily alter DNA sequences and modify gene function.

Colossal, a bioscience company recently co-founded by Harvard University geneticist George Church, aims to leverage this technology to resurrect the wooly mammoth or at least a creature very closely resembling one.

In a nutshell, the idea is to sequence DNA from samples of mammoth tusks, bones, and other materials. This genetic material would then be inserted into the Asian elephant stem cells, which would be used to make an artificial womb and a fertilized egg to breed a mammoth-elephant hybrid.

To explore the feasibility of such a lofty goal, Gilbert’s team attempted to reconstruct the genome of the Christmas Island rat, also known as Maclear’s rat (Rattus macleari), a species of rodent that went extinct in the early 1900s.

The team was able to reassemble most of the extinct rodent’s genome thanks to bits of code gleaned from the genome of the closely related Norwegian brown rat (Rattus norvegicus). Researchers were able to recover 95% of the Christmas Island rat’s genome, which sounds like a lot. Except, it’s not.

The last 5% of the genome they couldn’t make sense of is actually the most crucial part since it corresponds to the genes that differentiate the Christmas Island rat from other living relatives.

Some of the genes the researchers were able to recover include those related to the expression of tissue like the hair and ears. The Christmas Island rat had characteristically long black hair and round ears. However, many other genes were lost, their DNA sequences being broken up into many tiny pieces that cannot be reassembled.

Lost genes include those involved in the rat’s immune system and sense of smell. Cutting and pasting genes from another rat species is not really an option since smell plays a crucial role in foraging food, avoiding predators, and mating, so a modified animal might look and behave differently from the original extinct species.

Credit: Royal BC Museum Victoria.

Gilbert describes reassembling the genome of an extinct species as trying to piece together every page of a shredded book. If you have an intact copy of the original book, you should be able to reconstruct the original material perfectly. It might take you a while, but you’ll get there. But herein lies the problem: there are no more original copies for the genome of an extinct species.

Your next best bet is to compare your shredded pages to a similar book, but that means you’ll never be able to recover the missing pages that don’t match, even if you manage to deduce some of the content. The Christmas Island rat diverged from its Norwegian brown rat cousin about 2.6 million years ago. Due to this evolutionary divergence, most of the genetic information sequenced from old Christmas Island rat biological samples is simply lost. And this divergence is pretty similar to that between the woolly mammoth and the Asian elephant.

Some of this missing data could be recovered using current solutions or some that will be developed in the future. But the sad reality may be that some data will never be recovered, which makes the perfect resurrection of an extinct species impossible.

That being said, it’s not impossible to breed an animal that looks and behaves very closely to what you’d expect from an original mammoth or Tasmanian tiger. It’s just that these would be some hybrids of some sort, with combined features from both extinct and living species.

Ultimately, these findings don’t change much about the developments of scientific projects currently underway to resurrect extinct species. However, the study is still valuable because it helps clarify the limits of what’s actually possible. With a tighter straitjacket, maybe scientists’ imagination is diverted to more useful pathways of research. For instance, some of these efforts may be better placed in saving vulnerable species from extinction. Just saying.

The findings appeared in the journal Current Biology.

Raptor birds around the world are in decline, as they struggle with habitat loss and poisoned foods

Birds of prey are declining all throughout the world, according to new research, putting the health of ecosystems at risk. Habitat destruction is the main driver of this decline.

Image via Pixabay.

The paper analyzed data from the International Union for the Conservation of Nature (IUCN) and BirdLife International, a global partnership of non-governmental organizations involved in the conservation of birds and their habitat. Overall, the data showed that around 50% of the 577 bird of prey (raptor) species worldwide are declining in number. Roughly 30% are threatened, vulnerable, endangered, or critically endangered, with 18 species falling into the latter category.

Several species are also at risk of becoming locally extinct, even if they’re faring relatively okay as a whole species, the team explains. This means that they would no longer be able to act as top predators in certain ecosystems, a role critical for ecosystem health.

Bird issues

“The golden eagle is the national bird of Mexico, but we have very few golden eagles left in Mexico,” said Gerardo Ceballos, a bird scientist at the National Autonomous University of Mexico and co-author of the study.

The main threat to these birds is habitat destruction, the team explains, both through the direct issues it creates for them, such as a lack of adequate nesting areas, increased in-species competition for space and resources, as well as through indirect effects, including lower populations of animals that serve as prey.

Over half of raptor birds that are most active during the day (54%), including most hawks, eagles, and vultures, are showing ongoing population declines. Nocturnal raptors are faring somewhat better, with only 47% of species in this category showing population decline. This showcases that birds are experiencing strong pressures right now, not past pressures that have affected their numbers but have been addressed in the meantime. In other words, affected species will only fare worse over time, and it’s possible that new ones will also start being affected unless action is taken.

Apart from habitat destruction, other leading causes for the decline of raptors highlighted in the study include compounds such as rodent poison, used in agriculture, and lead shot that is typically used for hunting birds. Raptors routinely feed on rodents and carrion, so these compounds inadvertently affect them. Heavy use of anti-inflammatory drugs in livestock is also propelling the rapid decline of raptors, through the same mechanism. This is an issue particularly in South Asia, where some species have declined by 95% in recent decades due to the consumption of livestock carcasses.

The paper lists 4,200 sites previously identified by conservation groups as being essential for the health of raptors globally. According to the team, most of these are not protected in any way, or only enjoy partial coverage by protected areas. To illustrate how this state of affairs can impact raptor communities over a wide geographical range, the authors give East Asia as an example. Raptor species here tend to breed in north China, Mongolia, or Russia, and then migrate down the eastern coast of China to spend summers in Southeast Asia or India.

Multiple species will thus travel through a handful of sites throughout their migrations, so issues in any one of them will have wide-ranging impacts. Eastern China, for example, is very densely populated and highly urbanized, so sites in this area are facing massive pressures from human activity, including habitat destruction and contamination with agricultural compounds.

The paper “Global patterns of raptor distribution and protected areas optimal selection to reduce the extinction crises” has been published in the journal PNAS.

Biodiversity loss, fueled by human activity, could take millions of years to recover

Biodiversity loss is one of the most concerning issues facing us today. The rate at which species are going extinct is comparable to — and sometimes higher than — the rates seen during mass extinction events of the past. A new paper analyzing this issue in the context of freshwater ecosystems reports that it would take millions of years to undo the damage caused by human activity.

Image via Pixabay.

We are going through a period of incredibly high biodiversity loss rates, so much so that our modern times are often called the 6th mass extinction. A large part of the problem, like it or not, is human activity. We’re simply so successful as a species, taking up so much space and resources, that other forms of life are struggling to fit into the world today. Habitat destruction, climate change, overexploitation of natural resources, pollution, and invasive species are some of the leading causes of extinction right now.

A new study looking at extinction rates in freshwater ecosystems explains that species are disappearing faster today than they did during the end-Cretaceous extinction, the one that killed the dinosaurs. The damage we’re witnessing would take millions of years to undo, they add.

No room to share

“Losing species entails changes in species communities and, in the long run, this affects entire ecosystems. We rely on functioning freshwater environments to sustain human health, nutrition, and freshwater supply,” says lead author of the study, Dr. Thomas A. Neubauer from the Justus Liebig University Giessen.

“Even if our impact on the world’s biota stops today, the extinction rate will likely stay high for an extended period of time. Considering that the current biodiversity crisis advances much faster than the mass extinction event 66 million years ago, the recovery period may be even longer. Despite our short existence on Earth, we have assured that the effects of our actions will outlast us by millions of years.”

For the study, the team — an international group of evolutionary biologists, paleontologists, geologists, and modelers — compared today’s crisis with the previous, 5th mass extinction event, which was produced by the impact of the dinosaur-killing asteroid 66 million years ago. That event wiped out an estimated 76% of all species on the planet, including whole groups, such as the dinosaurs.

The authors focused their study on freshwater species, which are among the most threatened in the world. A large dataset was put together, containing 3,387 fossil and living snail species of Europe from the past 200 million years. Based on this, they estimated the rates of speciation (new species evolving) and extinction (species disappearing) over the 200 million year span, and proceeded to compare these to the rates seen today.

One of the most interesting findings is that the extinction rates estimated for the 5th mass extinction were much higher for freshwater biota than previously assumed. What’s worse, however, is that even this higher estimated rate is dwarfed by what the team believes we’ll be seeing in the future. On average, they estimate that the future rates of extinction will be three orders of magnitude higher than those observed during the time the dinosaurs went extinct. Such a pace is completely unprecedented and wasn’t reached even during the most intense extinction crises of the past.

By 2120, they add, a third of freshwater species living today will have died off.

One final and worrying implication of the research is how long nature seems to need in order to heal itself. Although the 5th extinction crisis was caused by an asteroid impact — a blink of the eye in geological terms — extinction rates remained elevated for around 5 million years and the Earth took around 12 million years to go back to normal extinction rates.

Such an extremely long timeline suggests that today’s extinction crisis could have immense consequences for wildlife in the future, taking millions of years to fix.

The paper “Current extinction rate in European freshwater gastropods greatly exceeds that of the late Cretaceous mass extinction” has been published in the journal Communications Earth & Environment.

Sawfish could soon become completely extinct if we don’t stop overfishing, says a study

A new study from the Simon Fraser University (SFU) warns that one of the most distinctive marine species — sawfish — are at real risk of extinction due to overfishing.

Image via Pixabay.

Sawfishes have already disappeared from roughly half of their known range, the authors report, as overfishing is driving their numbers into the ground. The species used to be quite a common sight for around 90 coastal countries around the globe, but are now one of the most threatened family of ocean fish and presumed extinct in 46 of those nations. A further 18 countries presume at least one species of sawfish to be locally extinct, while 28 others presume at least two.

A fish in need

“Through the plight of sawfish, we are documenting the first cases of a wide-ranging marine fish being driven to local extinction by overfishing,” says Nick Dulvy, one of the two authors of the paper.

“We’ve known for a while that the dramatic expansion of fishing is the primary threat to ocean biodiversity, but robust population assessment is difficult for low priority fishes whose catches have been poorly monitored over time. With this study, we tackle a fundamental challenge for tracking biodiversity change: discerning severe population declines from local extinction.”

Sawfishes get their name from the highly distinctive rostra they sport. These are long and narrow noses lined by teeth, making them very similar to sawblades. According to the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, three of the five species of sawfish alive today are critically endangered, with the other two being endangered.

According to the authors of this study, overfishing is to blame. The animals’ long rostra and the teeth they sport can easily become entangled in fishing nets. They can fetch a high price on the market as their fins are among the most pricy shark fins. Rostra can also be sold for a variety of reasons, from folk medicine and novelty to spurs used in cockfighting.

Although we have no reliable global account of sawfish numbers, Dulvy says that the data we do have paints a very bleak picture. Unless an effort is made to stop overfishing and protect the habitats these species live in, there’s a very real risk of them going completely extinct.

In regards to solutions, the team recommends a concerted international conservation project focusing on Cuba, Tanzania, Columbia, Madagascar, Panama, Brazil, Mexico, and Sri Lanka, where such efforts are likely to see the greatest payoff. Fishing restrictions in these countries could also help. Australia and the United States both have solid protections already in place and retain populations of sawfish — they should act as “lifeboat” nations to ensure the species doesn’t go the way of the dodo.

“While the situation is dire, we hope to offset the bad news by highlighting our informed identification of these priority nations with hope for saving sawfish in their waters,” says Helen Yan, the paper’s other co-author.

“We also underscore our finding that it’s actually still possible to restore sawfish to more than 70 percent of their historical range if we act now.”

The paper “Overfishing and habitat loss drive range contraction of iconic marine fishes to near extinction” has been published in the journal Science Advances.

Parrots are facing extinction, and only policymakers can save them

Parrots may not be very long for this world — and it’s on us. New research finds that parrot species around the world are threatened with extinction due to wide-spread habitat destruction. Current protected areas can’t mitigate these losses, the team adds.

Image credits Will Zhang.

Pressures from human activity is putting parrot species at risk of extinction all around the world. As such, the future of these birds is firmly in the hands of policy makers in Australia and other areas where parrots are endemic, the authors explain. Agriculture and logging are the biggest culprits that the team identified, but other events (such as the Australian wildfires of last year) are also contributing to the problem.

Parrotn’t?

“In a previous global evaluation of parrots with scientists from BirdLife International we showed that they are among the most threatened bird orders, with higher extinction risk than other comparable bird groups,” co-author Dr. George Olah, from the ANU Fenner School of Environment and Society, said.

As their current range experiences significant habitat destruction, parrot species are struggling to adapt all over the world. Those areas that are currently designated as protected are much too small to serve as alternative home for them.

The study is a product of a collaboration between parrot ecologists at The Australian National University (ANU) and spatial ecologists from the National University of Córdoba, Argentina. It looked at and compared the conservation status of parrots in different areas of the planet in order to come up with a wide-scale picture of the threats they face.

Over half of the world’s critically endangered species of parrot live in Australia, Asia, and the Pacific area, the team explains. Apart from habitat destruction, wildlife trade is further pushing parrot species towards extinction here.

The team explains that temperate forests in Australia (which house many species of parrots) were already showing signs of heavy degradation in 2020 due to human-modified landscapes. They project that this trend will continue and worsen the health of these ecosystems by 2050.

“We predicted that agricultural expansion will have a further negative effect on the conservation status of parrots, pushing many of their species to the edge of extinction in the near future,” co-author Dr. Javier Nori said.

The team identified four hotspots of parrot biodiversity, two in the Neotropics and two in Oceania, noting that each faces “different degrees of threat in regard to current habitat loss and agricultural trends”. They add that the findings “suggest the future of the group is subject to policymaking in specific regions, especially in the northeastern Andes and the Atlantic Forest”.

Deforestation, fueled by the need for arable land, remains a dire threat for parrots. These birds are “highly dependent on forests,” the authors explain, and could be pushed “to the edge of extinction in the near future” as more land is cleared. Policymakers can help protect the birds’s habitat and expand on current protected areas, or even set up new ones in the hotspots.

The paper “Global trends of habitat destruction and consequences for parrot conservation” has been published in Global Change Biology.

Climate change wiped out five human relatives, new study says. Are we next?

Sudden shifts in the global climate altered the climate niche for early humans. These changes happened to fast for them to adapt in time, leading to their extinction.

Since the Pliocene (5.3 million-2.6 million) all the way to the Pleistocene (2.6million — 11,600 years ago), at least six different species of Homo roamed the Earth. All but one went extinct and, according to a new study led by researchers at the Università di Napoli Federico II in Italy, climate change was to blame for their ultimate downfall. In the context of intensifying anthropogenic global warming, these findings serve as a stark warning.

“The picture of a live drama”

For their new study, the researchers led by Pasquale Raia of Università di Napoli Federico II examined an extensive fossil database spanning more than 2,750 archaeological records. Their primary goal was to see how early humans reacted to changing climates over the last 5 million years, but much to their surprise, they found that all species besides Homo sapiens eventually reached a point in time when they simply couldn’t adapt anymore.

“Extinct Homo species went through a sudden, abrupt drop in the variability of climates they were able to survive in just before extinction only at that moment. When we tested whether global change made them vulnerable compared to Homo sapiens, we found climate change is the culprit for the drop. The initial goal of the study was to understand how Homo species adapted to climate change, we didn’t expect to find anything like that,” Raia told ZME Science.

Raia and colleagues looked at records that involved six species of early humans: H. habilis, H. ergaster, H. erectus, H. heidelbergensis, H. neanderthalensis, and H. sapiens. Virtually all of them were widely distributed and employed sophisticated tools. In the case of Neanderthals and modern humans, we know for a fact that these species also employed complex cultural practices, advanced tools such as glued spear points, and wore clothes.

This is why the anthropologists expected these species to have a relatively constant climatic niche relative to their evolutionary climatic niche. Every terrestrial species has a realized climatic niche, which is the set of large-scale temperature and precipitation conditions where that species occurs. But the results of this analysis suggest that H. erectus, H. heidelbergensis, and H. neanderthalensis lost a significant portion of their climatic niche just before going extinct. For Neanderthals, this environmental pressure due to sudden changes in the global climate was made worse by competition with H. sapiens.

“The first time I saw the plot of average climatic niche width against time, my colleague Mirko Di Febbraro, who produced that plot for Neanderthals, called me on the phone and said: ‘Pas, I’ve shared the plot via mail with you. I’m sorry man, it makes no sense, it is completely random except for the last moment, there should be something wrong there,’ to which I retorted: ‘nothing wrong bro, that moment is the picture of a live drama, we have found something!'” Raia told ZME Science in an email.

While there are inherent uncertainties in paleoclimatic reconstructions, the researchers believe that their findings show that climatic conditions were simply too extreme for these extinct species just before the timeline of their extinction. “When they went extinct, it was just too much of climatic change for them, more than they had to withstand in their lifetime,” Raia said.

It’s not clear why humans survived while all our other relatives perished. Perhaps we had superior technology or perhaps we were just lucky. Needless to say, today we are in the midst of a new, sudden shift in the global climate.

The world is nothing like it was during the Pleistocene, and that’s largely owed to our activity that has extensively altered the landscape and biosphere.

In our arrogance, we often place ourselves outside the natural world. However, that’s poor, misguided judgement. We are all part of an interdependent ecological system, and when a tipping point is reached, the entire system can crumble. Our close extinct relatives weren’t necessarily less intelligent than us, yet they perished.

The message is pretty clear: climate change sounded the death knell for our ancestors. These findings, which appeared in the journal One Earth, shouldn’t be taken lightly.

For the moment, Raia is busy with other research destined to reveal spicy new details about the ancient lives of our ancestors.

“We have a new paper out for iScience right now, showing that cultural modernity in humans could be as much as one million years old, that’s terrific!” he said.

Scientists around the world call on governments to protect cetaceans or risk seeing them go extinct

Scientists and conservationists from 40 countries have signed an open letter calling for global action to protect cetaceans (whales, dolphins, and porpoises) from extinction. Half of all species are of conservation concern, with two on the edge of extinction according to the researchers, who called for urgent action.

Credit Flickr Isaac Kohane

“Let this be a historic moment when realizing that whales are in danger sparks a powerful wave of action from everyone: regulators, scientists, politicians and the public to save our oceans,” Mark Simmonds, a visiting research fellow at the University of Bristol who coordinated the letter, told the BBC.

Of the 90 living species of cetaceans, more than half now have a concerning conservation status according to the International Union for Conservation of Nature (IUCN). Thirteen species listed as “Critically Endangered” or “Endangered,”, seven as “Vulnerable” and seven as “Near Threatened,” whilst 24 species are “Data Deficient”. Additionally, there are 32 subspecies and other distinct cetacean populations that are presently either Endangered or Critically Endangered. With ongoing research, scientists are recognizing more populations of cetaceans that are discrete and require conservation action, the letter reads.

Environmentalists came up with the “save the whales” slogan in the 1970s, which spread around the world and created a movement to end commercial whaling. Although disturbed populations in most parts of the world have had a chance to recover from organized hunting, they are now facing myriad threats from human actions.

Cetacean populations are adversely affected by many interacting factors, including chemical and noise pollution, loss of habitat and prey, climate change, and ship-strikes. For many, foremost among these threats is fishing. An estimated 300,000 cetaceans are killed because of fishing every year.

This has raised the alarm among scientists, who argued we are moving closer to a number of preventable extinctions. And unless we take action now, future generations won’t experience a large number of these creatures. They recalled the decline of the North Atlantic right whale and the vaquita, a porpoise species with only 10 surviving individuals. And these will be followed by the inevitable decline of the baiji or Chinese river dolphin.

The baiji was identified as ‘Possibly Extinct’ by the IUCN in 2017 and, regrettably, there is little hope for this species, the scientists argued. In all cases, enough was known over the decline but there was a lack of political action.

Speaking with the BBC, Susan Lieberman of the Wildlife Conservation Society said she signed the letter to help scientists raise these issues more widely. “It is critical that governments develop, fund, and implement additional needed actions to better protect and save these iconic species – so they don’t end going the way of the baiji,” she said.

The scientists called on countries with cetaceans in their waters to take precautionary action to ensure these species and populations are adequately protected from human activities. This includes implementing appropriate and fully resourced monitoring. Improved technologies now offer new opportunities to observe and address problematic activities at sea.

At the same time, they asked all nations to work with and strengthen the relevant international bodies that seek to address threats to cetaceans. This mainly refers to the International Whaling Commission and the Convention for the Conservation of Migratory Species of Wild Animals. Both are generating important conservation initiatives, they argued.

“Whales, dolphins and porpoises are seen and enjoyed all over the world, and are valued as sentient, intelligent, social and inspiring species; we should not deny future generations the opportunity to experience them. They are also sentinels of the health of our seas, oceans and, in some cases, major river systems,” the letter concludes.

UK butterflies need more shady spots or risk dying to climate change

New research shows that butterflies in the UK (and perhaps everywhere else in the world) are at greater risk of decline due to climate change than other species.

Image via Pixabay.

Most butterflies are ectotherms. This means that, similar to reptiles, they can’t create their own body heat, and need to absorb it from their environment. It’s not about warming up, either — butterflies also need to use their environment to cool down, chiefly by seeking out shady areas.

Given that average temperatures and weather patterns are bound to change as the climate heats up, this trait could place butterflies at a higher risk of extinction, as they may struggle to maintain an appropriate body temperature.

Too hotterflies

“As we plan conservation measures to address the effects of climate change, it will be important to understand not only the habitat requirements of different butterfly species, but also their temperature requirements,” said Dr. Ed Turner from the University Museum of Zoology, Cambridge, lead author of the paper.

Two-thirds of the UK’s butterfly species are already in decline, the team writes, mostly due to habitat loss and fragmentation. Climate change is only going to amplify these issues as ecosystems around the world shift and adapt to the new conditions, or simply buckle under the stress. The greater frequency and intensity of extreme weather events we’re bound to see in the future will also negatively affect butterflies, the team writes.

The current paper explains that there are significant differences in the ability of individual butterfly species that live in the UK to withstand such changes. Some species rely more heavily on environmental shade to cool down, for example, and these face the greatest risk. The findings are based on nearly 4,000 wild butterflies across 29 species captured using hand-held nets in the UK. The temperature of these insects was recorded using a fine probe then compared to the temperature of the air around them, or that on the perch where they were found. This data, the team explains, helped us understand the degree to which buterflies use their environment to regulate their temperatures.

Larger and more pale species of butterflies should fare the best, the team explains, as they can better manipulate incoming sunlight (and thus, heat) from their large, reflective wings. These insects angle their wings in relation to the sun and perform motions that directs heat towards or away from their bodies. Even today, such species have either stable or growing populations.

More colorful species have a harder time controlling their temperature using the same approach, the team explains. Worse-off are butterflies that are both colorful and tiny, they add, who have virtually no natural ability to control their body heat and must rely almost completely on their environment for the task.

Some buterfly species rely finding spots with specific termperature within a landscape (known as “microclimates”) to regulate body heat. A shady patch of ground is noticeably cooler than one in full sunlight, for example, and some species rely extensively on these small differences to keep internal heat just right. Sadly such species, including Brown Argus (Aricia agestis) and Small Copper (Lycaena phlaeas), have seen the worst declines over the last four decades — and are likely to fare the worst in the future.

Protecting these species can be as simple as ensuring a high diversity of landscape, the team argues. Diverse landscapes have nooks and crannies that allow for a much greater variability in microclimates, ranging in scale from centimeters (such as ditches, hedges, or flower patches) to kilometers (such as hillsides or ravines).

So why would we care about the butterflies? Well for one, they’re an integral part of today’s ecosystems, and their going extinct would impact all the species that rely on them as prey. But butterflies are also important pollinators, fertilizing around 85% of the plant species that serve as food crops in the UK, according to the team. Protecting them would thus help ensure our food security in the future, and make agriculture more resilient to shocks (as having several species of pollinators available is much safer than having a single one).

Insects, including butterflies, pollinate around 85% of our food crops—providing a vital service worth billions of pounds globally. Protecting a diverse range of species will provide long-term resilience: if numbers of one species fall there are others to fill the gaps. Insects are also an important food source for many other species, including birds.

We need to make landscapes more diverse to help conserve many of our butterfly species. Even within a garden lawn, patches of grass can be left to grow longer—these areas will provide cooler, shady places for many species of butterfly,” says Dr. Andrew Bladon, a Postdoctoral Research Associate in the University of Cambridge’s Department of Zoology, and first author of the report.

“In nature reserves, some areas could be grazed or cut and others left standing. We also need to protect features that break up the monotony of farm landscapes, like hedgerows, ditches, and patches of woodland.”

The findings, while focusing on buterflies, point to a much larger problem. Insects overall are struggling all over the world due to human activity, and climate change is poised to make their life even harder. Natural ecosystems and our very way of life are directly underpinned by insects — so if they go, we’ll probably go with them.

The paper “How butterflies keep their cool: Physical and ecological traits influence thermoregulatory ability and population trends” has been published in the Journal of Animal Ecology.

Photograph of Sir David Attenborough seated at the Great Barrier Reef, taken for his Great Barrier Reef series. Credit: 2015, Wikimedia Commons.

‘Extinction: The Facts’: Attenborough’s new documentary is surprisingly radical

Photograph of Sir David Attenborough seated at the Great Barrier Reef, taken for his Great Barrier Reef series. Credit: 2015, Wikimedia Commons.

Photograph of Sir David Attenborough seated at the Great Barrier Reef, taken for his Great Barrier Reef series. Credit: 2015, Wikimedia Commons.

We have learned so much about nature from David Attenborough’s documentaries over the past seven decades. In a new BBC film he lays bare just how perilous the state of that nature really is, why this matters for everyone who shares this planet, and what needs to change.

This film is radical. Surprisingly radical. I have written in the past about my growing frustration with Attenborough documentaries continuing, decade after decade, to depict nature as untouched by any mark of humans. I felt this might be contributing to unhelpful complacency about how much “wild” was really left.

Extinction: The Facts” is a significant departure. As one of the programme’s talking heads, I helped reveal the honest truth: in most places, remaining natural habitats are squeezed between intensive agriculture and urban sprawl.

The film starts with a bleak interview with James Mwenda, the keeper of the world’s last two northern white rhinos; a mother and daughter pair. “When Najin passes away”, says Mwenda, “she will leave the daughter alone forever … Their plight awaits 1 million more species”.

This sequence has a real emotional kick. However, the film makes clear that extinction is about so much more than the loss of large familiar mammals.

“Everything is joined up, from a single pond to a whole tropical rainforest” says Kathy Willis professor of biodiversity at the University of Oxford. “We tend to think we are somehow outside of that system. But we are part of it; and totally reliant upon on it”. The film goes on to explain the impacts of biodiversity loss on our soil functioning (with a star turn from below-ground beasties breaking down leaf litter), the role of insects in pollinating our crops, and how losing trees and wetlands can contribute to landslides and floods.

The documentary features Najin and Fatu, the last two northern white rhinos (pictured here with former head caregiver Mohammed Doyo). Dai Kurokawa / EPA

The potential link between the drivers of biodiversity loss and emerging diseases is also explored. The wildlife trade brings 1,000s of stressed animals into close contact, providing the perfect opportunity for viruses to jump) between species. At the same time, removing large predators results in increased abundance of rodents and bats which are more likely to carry dangerous viruses. “We’ve been changing biodiversity in critical ways which made [the pandemic] more likely to happen”, says Peter Daszak of Ecohealth Alliance.

In footage from the 1992 Earth Summit in Rio, then 12-year-old Severn Suzuki addresses the largest UN meeting to have ever convened. “We are a group of 12 and 13 years olds come to tell you adults that you must change your ways”. The parallels with Greta Thunberg’s recent high-profile speech to the UN serve to highlight how little progress has been made.

So if biodiversity loss is so obviously happening, and so obviously a bad thing for the future of humanity, why have we failed to act and what needs to be done?

Firstly, the film makes it clear that a key ultimate driver is consumption in rich countries. Given that the average Brit consumes more than four times the resources of the average Indian, reducing consumption in places like the UK is vital. This need not be painful. As the eminent Cambridge economist Partha Dasgupta says, “40 years ago people in the UK consumed a good deal less. But there is no evidence that we were unhappier then”. The film starkly highlights what we are losing in exchange for out-of-season food, fast fashion and cheap poultry.

Secondly, having strong environmental standards for things produced in the UK (important though it is), is not enough. We also need to consider where the products we buy and the food we eat comes from – if not, people in countries like the UK are simply offshoring environmental problems for others to deal with.

Finally, the film touched on the need to make us pay the true cost of the environmental damage we do. The idea that businesses should not be able to degrade our environment for free is far from new. However, despite some progress with policies like the UK’s landfill tax or California’s carbon trading scheme, most societies are far from doing this comprehensively.

Together, this is what makes the film so radical. It is explicitly calling for major changes in the way our economies work with a greater focus on both planetary boundaries and global inequality. I was certainly surprised to see this weaved into a Sunday night BBC prime time show.

Towards the end, the film moves back to more conventional conservation territory to insert a much-needed dose of optimism. The final story includes some of the most iconic footage from Sir David’s career: his meeting with Rwanda’s mountain gorillas 40 years ago. At the time, Attenborough felt he might be seeing some of the last of their kind – just 250 individuals were left and their future looked bleak. Today that population is doing much better.

Over his incredible career, David Attenborough has seen more of earth’s natural wonders than almost anyone. To hear him talk, with such clarity, about how bad things are getting is deeply moving. Scientists have recently demonstrated what would be needed to bend the curve on biodiversity loss. As Attenborough says in the final scene, “What happens next, is up to every one of us”.The Conversation

Julia P G Jones, Professor of Conservation Science, Bangor University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The world’s herbivores are in trouble, more so than its predators

Herbivores are facing a greater risk of extinction than predators or omnivores, a new study finds. Megaherbivores (species that grow up to more than 1000 kg) are particularly affected, and their loss will send massive ripples across ecosystems.

Image credits Penny Ash.

The Earth is no stranger to extinction. It’s a natural process, and the rate at which species disappear in the wild is known as the ‘baseline extinction rate’. It’s a bit sad to see species go, obviously, but this process helps remove under-performing actors, or those who can’t adapt, to make room for new ones to evolve.

While this natural extinction rate helps keep the world healthy, human activity is putting immense pressure on the planet, resulting in a greatly accelerated rate of extinction. And it’s disproportionately affecting plant-eaters.

Killing the middleman

“The results were somewhat shocking,” says Trisha Atwood, an Assistant Professor of Watershed Sciences at Utah State and lead author of the study.

“Our highly publicized and fraught relationship with predatory animals such as lions and wolves has led to the unfounded perception that we are losing predators more than any other trophic group.”

This isn’t the first time that human activity has led to the extinction of large herbivorous species. A similar phenomenon took place one million years ago, likely driven by human expansion and hunting, which forever changed the shape of life on our planet.

The disappearance of large herbivores reduced pressure on plantlife, changing growth and population dynamics. This altered fire regimes (there was more fuel, i.e. uneaten plant matter) and impacted nutrient cycling (nutrients are produced by plants and concentrated by herbivores). All in all, such changes lead to the Earth becoming colder — more plants and fewer plant-eaters equals less CO2 in the atmosphere.

The findings suggest that megaherbivores today could experience the same fate, and the consequences of such a change are yet unknown.

The team looked at the diets and threatened status of over 24,500 species of mammals, birds, and reptiles to see which category of animals (herbivores, carnivores, or omnivores) are most at risk of extinction. Their findings indicate that over 25% of today’s herbivore species are faced with extinction, which represents the highest risk margin for any of the studied groups. The team notes that herbivores have been experiencing a disproportionately high rate of extinction since at least the late Pleistocene 11,000-50,000 years ago.

Who needs help the most

The authors say that dispelling misconceptions (such as ‘carnivores are more at risk of extinction than herbivores’) is essential if we’re to fix the issues we’re causing. Different groups of species have different ecological functions, so the loss of each would have a different effect on the balance of nature.

The changes we’re seeing now are similar to those seen 1 million years ago, the authors note: changes to plant species and their population numbers, changes in fire regimes, disruptions in nutrient recycling.

Better management and conservation of herbivores is needed to prevent unpleasant changes in the future, such as dramatic shifts in or complete collapse of natural ecosystems. Since herbivores are a key part of global food webs (both wild and human-run), their loss isn’t an encouraging prospect.

The study highlights that herbivores are faring the worst, but predators aren’t having it easy, either. Scavengers, species that eat the remains of recently deceased animals, and species that primarily eat fish, are also facing a higher risk of extinction.

“Our results enable us to identify specialized diets within the carnivores that are associated with higher extinction risk, and also identify the habitats these species live in,” says Edd Hammill, an assistant professor of watershed sciences at Utah State University and co-author of the study.

“It would appear that seabirds across the globe suffer disproportionately high levels of extinction.”

Understanding the patterns of extinction facing different species groups is only the first step to protecting their health. Next, the team plans to examine what drives these extinctions, so we can focus our efforts on the root of the problem itself.

The paper “Herbivores at the highest risk of extinction among mammals, birds, and reptiles” has been published in the journal Science Advances.

Human activity might undo more than 50 billion years of evolution

Baby pangolin. Credit: Yingboon Chongsomchai, ZSL.

Researchers from the Zoological Society of London (ZSL) and Imperial College have completed one of the most comprehensive analyses of the evolutionary history of terrestrial vertebrates and how countless species of amphibians, birds, mammals, and reptiles are being impacted by human activity — as expected, it’s not pretty at all.

“We found that the most important areas for global evolutionary history are facing much higher levels of human pressure than we expected, with 3/4th of the most diverse regions under high or very high human pressure. Conversely, just 5% of these critical areas are under little or no human pressure,” lead author Rikki Gumbs, of ZSL’s EDGE of Existence programme and the Science and Solutions for a Changing Planet Doctoral Training Partnership at Imperial College London, told ZME Science.

“When we quantified the scale of impact by human activities across the tree of life for amphibians, birds, and mammals, we found it to be incomprehensibly large: close to 50 billion years of unique evolutionary history is at risk of being lost forever due to humanity’s actions. Numbers that large are typically associated with astrophysics, not biodiversity.”

This was the first time that researchers have investigated how areas with important concentrations of evolutionary distinct and threatened species are being impacted by human activity.

Although it’s not secret that humans are driving many species extinct through habitat encroachment, hunting, fishing, and wildlife trade, the new study has revealed important insights that animal conservation may have missed before.

For instance, the authors conclude that many regions of the world that are home to the greatest amount of unique evolutionary heritage are also some of the most affected by human footprints. These include the Caribbean, the Western Ghats in India, and large regions of Southeast Asia.

In order to figure out the amount of evolutionary history currently threatened with extinction, the researchers turned to data relevant for around 25,000 species.

“We embarked on this study for several reasons. First, we understand that the tree of life is an extremely important component of the world’s biodiversity. It is linked to ecosystem productivity and to future benefits for humanity. Identifying what species and regions across the planet are highly evolutionarily unique and facing intense human pressure will allow us to target conservation efforts to better understand and conserve these unique and amazing species and places,” Gumbs said.

The Mary River turtle (Elusor macrurus) is an endangered short-necked turtle that is endemic to the Mary River in south-east Queensland, Australia. Credit: ZSL, Chris Van Wyk.

After combing through hundreds of gigabytes of data and making sense of huge datasets, Gumbs and colleagues were stunned by the results of their calculations.

“I still remember having to double-check my calculations when I found that we stand to lose close to 50 billion years of evolutionary history across amphibians, birds, mammals, and reptiles! I counted and re-counted the number of zeroes to make sure I wasn’t making a mistake before emailing my supervisor. Unfortunately for the tree of life, my estimates weren’t a mathematical error,” he recounted.

All living things on Earth can trace their descent back to a common ancestor. However, smaller groups of species can also trace their ancestry back to common ancestors, often a much more recent one.

Phylogenetic trees map these relationships, with common ancestors acting as branch points. Biologists draw the branching tree of life by grouping species by shared characteristics that illustrate the degree of relatednesses, such as external morphology (shape/appearance), internal anatomy, behaviors, biochemical pathways, DNA and protein sequences, and even the characteristics of fossils.

However, not all branches are equal. Some are broad and rich, encompassing many living related species, while others are short and stubby. Then, there are branches in the tree of life where only a single species is still left — when that species dies, the entire lineage disappears with it.

For instance, the researchers found that human activity is threatening groups of closely-related species that share long branches of the tree of life, such as pangolins and tapirs. However, some of the species that face extinction belong on the tail end of extremely long branches. These include the ancient Chinese crocodile lizard (Shinisaurus crocodilurus), the Shoebill (Balaeniceps rex), a gigantic bird that stalks the wetlands of Africa, and the Aye-aye (Daubentonia madagascariensis), a nocturnal lemur with large yellow eyes and long spindly fingers. 

The shoebill (Balaeniceps rex) also known as whalehead, whale-headed stork, or shoe-billed stork, is a very large stork-like bird. Credit: ZSL, Claudia Gray.

As such, the study is offering a framework for conservation that highlights priority species, such as the punk-haired Mary River turtle (Elusor macrurus), the Purple frog (Nasikabatrachus sahyadrensis), and the Numbat (Myrmecobius fasciatus)

“All species are worth saving! Sadly, in conservation, we lack the resources to actually achieve this, given our huge impacts on the environment. Prioritising species based on their evolutionary uniqueness, as we do at the EDGE of Existence programme, should be seen as a complementary approach to other conservation efforts, such as preserving entire ecosystems and species critical to their environments that are perhaps not evolutionarily unique. However, as evolutionary history (as Phylogenetic Diversity) is a fundamental measure of biodiversity, saving species that are responsible for greater amounts of unique evolutionary history than others does represent a greater gain in the conservation of biodiversity at a global scale,” Gumbs said.

The reality may be even more depressing as this analysis is just the tip of the iceberg. The study did not account for the decline in biodiversity for insects (more than 40% of which are threatened by extinction), flowers, or fungi.

“Our work focuses on the world’s terrestrial vertebrates: amphibians, birds, mammals, and reptiles. We used these groups as they have the best data available. However, these species are just the tip of the iceberg in terms of the current extinction crisis. We don’t know how humanity is threatening the entire tree of life, from insects and fish to fungi and flowers. Hopefully we can gather enough data to expand our work to incorporate other groups of animals and plants that are also facing huge losses during this crisis,” Gumbs said.

“We hope this research can inspire others to develop a better understanding of, and provide effective conservation for, the species we highlight as priorities before it’s too late. This study highlights just how harmful our current global system is to the future of biodiversity, and we need to enact change at all levels before it’s too late for the world’s most unique and threatened diversity.”

The findings were reported in the journal Nature Communications.

Drought and human expansion are driving the platypus extinct

Woes seem to keep piling onto poor Australia: new research shows that the continent’s iconic and unique platypus is at risk of extinction.

Image credits hobvias sudoneighm / Flickr.

The intense and prolonged drought plaguing the land down under is placing enormous strain on the platypus, a new study reports. The rivers and waterways that make up this species’ natural habitat are drying up, leaving the animals stranded, the researchers explain.

Going through a lot

Although not much is known about their natural distribution or abundance (the species is nocturnal and quite shy), platypuses were once considered widespread throughout eastern Australia and Tasmania. However, new research led by members from the University of New South Wales (UNSW) in collaboration with the Taronga Conservation Society showcases that the species is in dire need of help. It is experiencing heavy pressure from both natural and man-made factors including severe drought, water resource development, land clearing, and changing climate. The team warns that action is urgently needed to save the platypus from potential extinction.

Lead author Dr Gilad Bino, a researcher at the UNSW Centre for Ecosystem Science, said action must be taken now to prevent the platypus from disappearing from our waterways.

“There is an urgent need for a national risk assessment for the platypus to assess its conservation status, evaluate risks and impacts, and prioritise management in order to minimise any risk of extinction,” says Dr. Bino.

“These dangers further expose the platypus to even worse local extinctions with no capacity to repopulate areas.”

The species is most impacted by current climate conditions and habitat destruction through land clearing and fragmentation from dams and weirs, the team reports. They further explain that platypus numbers have almost halved since European colonists first settled Australia, with local populations going extinct across 40% of the species’ range. Considering the current drought and the likely increase in drought frequency and duration in the future (due to climate change), things are only going to get worse for the platypus.

While the International Union for Conservation of Nature (IUCN) recently downgraded the platypus’ conservation status to “Near Threatened”, it remains entirely unlisted under most local jurisdictions except in South Australia, where it is considered endangered.

Apart from climate change and its associated extremes in weather and precipitation patterns, the chief threat to platypus’ long-term viability is humans, the team explains. The animals live or have traditionally lived in areas that are still experiencing extensive human development.

“These include dams that stop their movements, agriculture which can destroy their burrows, fishing gear and yabby traps which can drown them and invasive foxes which can kill them,” says study co-author Professor Richard Kingsford, also from the UNSW Sydney Centre for Ecosystem Science.

Luckily for the strange mammal, it’s not yet extinct. If preventative measures are taken now, says Professor Brendan Wintle, a study co-author from The University of Melbourne, we can turn their fortunes around. He explains that mitigating or stopping new threats (such as new dams) from impacting the species’ range can help “even a presumed ‘safe’ species such as the platypus”.

Still, the paper highlights the “urgent need” for national conservation efforts focusing on the platypus. However, they add that many other native Australian species are also threatened with extinction.

“[Preventive measures are] likely to be more effective than waiting for the risk of extinction to increase and possible failure,” Prof Wintle said. “We should learn from the peril facing the koala to understand what happens when we ignore the warning signs.”

Such measures include “increasing monitoring, tracking trends, mitigating threats, and protecting and improving management of freshwater habitats.”

Meanwhile, the team plans to continue researching the ecology and possible conservation practices for the platypus to help guide effective policy and management programs in the future.

The paper “A stitch in time – Synergistic impacts to platypus metapopulation extinction risk” has been published in the journal Biological Conservation.

Neanderthal extinction could have been driven by inbreeding, demographic issues — not modern humans

Small populations and inbreeding may have driven the Neanderthals extinct, new research suggests.

Neanderthals disappeared sometime around 40,000 years ago, about the same time as modern humans began moving into Europe and the Near East. Because of the timing, it’s often held that modern humans helped drive our ancient relatives extinct, but this theory hasn’t been confirmed or infirmed up to now.

A new study looked at the population dynamics of Neanderthal groups in a bid to gain insight into their extinction. Through the use of demographic modelling, the team tried to establish if internal factors helped drive the Neanderthals out of history — and whether they were headed for collapse on their own, without the ‘help’ of modern humans.

Family ties

“Our results indicate that the disappearance of Neanderthals might have resided in the smallness of their population(s) alone,” the paper’s abstract reads. “Even if they had been identical to modern humans in their cognitive, social and cultural traits, and even in the absence of inter-specific competition, Neanderthals faced a considerable risk of extinction.”

The team used data from hunter-gatherer populations today as a guideline for their modeling efforts. After observing how these groups operate, the team developed population models for Neanderthal groups of various initial sizes: 50, 100, 500, 1,000, and 5,000 individuals.

The team then mixed in the effects of inbreeding, Allee effects (where reduced population size negatively impacts individuals’ fitness), and random demographic fluctuations (caused by shifting births, deaths, and sex ratios) into their simulated societies and observed the results. What they wanted to determine was if these factors were enough to drive the communities to extinction over a 10,000-year period.

Inbreeding alone was likely not enough to drive most Neanderthals to extinction. The team notes that it only led to the collapse of the smallest population modeled for the study. However, Allee effects could cause the extinction of populations up to 1,000 individuals strong when 25% of fewer Neanderthal females gave birth within a given year (the team reports that this is a common birth rate in hunter-gatherer societies today. When all three factors were together (inbreeding + Allee effects + demographic fluctuations), all the populations modeled in the study died out within 10,000 years.

Being based on computer models — which themselves are based on modern human hunter-gatherers — means that the findings should be taken with a grain of salt. While the models can’t account for everything, they do give us a general idea of what was happening to the Neanderthals at the time, the team reports.

It’s possible that the encroachment of modern humans impacted the Neanderthals in ways that promoted inbreeding and subsequent Allee effects, which obviously could not be accounted for by the models. However, even in the absence of modern humans, Neanderthals were headed to extinction due to their demographic issues, according to the findings.

The paper “Inbreeding, Allee effects and stochasticity might be sufficient to account for Neanderthal extinction” has been published in the journal PLOS ONE.

Koalas might not be functionally extinct — but they’re in huge trouble

There have been reports that 80% of the koalas’ habitat has been destroyed. If true, this could render the population functionally extinct. But the woes of the koalas are not new, and they’re not limited to the current wildfires, as some have suggested.

Image via Wikipedia.

Australia is experiencing record-breaking drought and bushfires. Deborah Tabart, chairman of the Australian Koala Foundation (the largest non-profit organization dedicated to koala conservation) estimates that over 1,000 koalas have been killed because of the fires and more than 80% of their habitat has been destroyed. A number of recent articles from major publishers made it seem like this drove koalas to the brink of extinction by these wildfires — but that’s not exactly true.

There is no doubt that the wildfires are putting koalas under massive threat, subjecting them to even more environmental stress than usual. However, the ‘functionally extinct’ label came from earlier this year — in May, to be precise.

Back then, the Australian Koala Foundation dropped a press release stating the organization believes that “koalas may be functionally extinct in the entire landscape of Australia” and that koala numbers could be as low as 80,000.

Functionally extinct means that the current generation of adults is insufficient to produce a new, functional generation. There are a few things to note here.

Koalas are indeed in major trouble (and we’ll get to that in a bit). However, the foundation never really explained how they got those numbers and why they believe koalas to be functionally extinct. Secondly, the press release was published at a delicate moment: right before Australia’s election, where climate change and its effects (such as increased drought and wildfires) was a key issue.

So understandably, it’s easy to link the current bushfires with the koala woes, but this would be unclear and misleading.

However, this doesn’t exactly mean ‘good news’ for koalas.

The world is currently undergoing a mass extinction, and even among current trends, Australia’s extinction rate is among the highest in the world. The koala, an animal which is synonymous with Australia’s image, is in severe decline, despite its beloved status.

It’s probably sufficient to produce healthy generations, but it is also true that once a koala population falls below a critical point it can no longer produce the next generation, leading to extinction.

The truth is, we don’t really know how many koalas there are left in the wild.

“To determine whether each population of koalas scattered across eastern Australia is functionally extinct would require a gargantuan effort,” wrote Christine Adams-Hosking, a conservationist at the University of Queensland, for The Conversation. “It’s incredibly difficult for scientists to get a full grasp on koala numbers across Australia, so categorizing the species as “functionally extinct” is difficult.”

The koala is in trouble. It’s listed as ‘Vulnerable’, but its true status might be significantly worse than that. Threatened by climate change and its effects, koalas will continue to decrease in numbers unless stronger action is taken. Even if they’re not functionally extinct, things don’t exactly look good for the adorable creatures. To date, the present “vulnerable” listing has not achieved any known positive results for koala populations, Adams-Hosking explains.

The threats to koalas remain present and intensifying. It’s not just climate change — deforestation and diseases also threaten koalas. We also know that koala populations in some inland regions affected by climate extremes such as severe droughts and heatwaves have declined by as much as 80%.

Koalas are just one piece of the puzzle. Their decline is synonymous with the decline of an entire ecosystem. For millions of years koalas have been a key part of the health of our eucalyptus forests by eating upper leaves, and on the forest floor, their droppings contribute to important nutrient recycling. Their known fossil records date back approximately 30 million years so they may have once been a food source for megafauna carnivores.

‘Lost’ deer species rediscovered after 30 years

Camera-trap photo of silver-backed chevrotain (Tragulus versicolor).
Image credits: SIE/GWC/Leibniz-IZW/NCNP / Andrew Tilker

The Vietnam mouse-deer (which also goes by the name of silver-backed chevrotain, or more technically, Tragulus versicolor) was first described in 1910, based on specimens near the city of Nha Trang, Vietnam. This bordering area between Vietnam and Laos hosts one of the richest biodiversities in the world. However, as of 1990, it was believed that the mouse-deer was no longer a part of that biodiversity.

High levels of hunting (particularly with snares) and habitat loss led the numbers of these deer to decline, with no official sightings being reported throughout the 1990s. Researchers feared that the species had gone extinct, which seemed to be more and more likely as years passed on.

But An Nguyen from the Leibniz Institute for Zoo and Wildlife Research wasn’t so sure. Along with Andrew Tilker and other colleagues, Nguyen set up a plan to find out whether the chevrotain is still around or it actually went extinct. They spoke to locals around the Greater Annamites Ecoregion of Vietnam and Laos who claimed to have seen the species. Their stories seemed consistent, but there was a problem: the silver-backed chevrotain looks a lot like other mouse-deer which inhabited the area.

So the research team set up 30 motion-activated cameras in the Nha Trang area to see whether they could find evidence of this critter.

“We had no idea what to expect, so I was surprised and overjoyed when we checked the camera traps and saw photographs of a chevrotain with silver flanks. For so long this species has seemingly only existed as part of our imagination.”

After six months of camera observations, the researchers confirmed over 200 detections (although it’s not clear how many individuals were observed). The locals were right in their claims that the species never went extinct, leaving researchers overjoyed.

” In an age of mass extinctions, confirming the survival of lost species provides rare second chances for biodiversity conservation,” researchers write. “The silver-backed chevrotain Tragulus versicolor, a diminutive species of ungulate known only from Vietnam, has been lost to science for almost three decades. Here, we provide evidence that the silver-backed chevrotain still exists and the first photographs of the species in the wild, and urge immediate conservation actions to ensure its survival.”

While it’s always exciting to rediscover a species once thought to be lost, the fate of the silver-backed chevrotain is not yet certain. At best, the species still hosts a small but healthy population. At worst, only a few individuals survive in the area, and the species is still on the brink of extinction.

Researchers have developed a mitigation plan dealing with the two main threats to the species: habitat alteration and poaching. Poaching is probably the more pressing issue of the to, so reducing snares is the first and very critical step in ensuring that we don’t lose the species again.

The study has been published in Nature.

Stop climate change or the Emperor penguins die, a new paper warns

Unless we get a grip on climate heating, the emperor penguin is going the way of the dodo — extinct.

Image credits Christopher Michel / Flickr.

An international study led by researchers at the Woods Hole Oceanographic Institution (WHOI) reports that warming climate conditions might cause emperor penguins (Aptenodytes forsteri) to become extinct by the end of the century.

The Emperor’s new environment

“If global climate keeps warming at the current rate, we expect emperor penguins in Antarctica to experience an 86% decline by the year 2100,” says Stephanie Jenouvrier, a seabird ecologist at WHOI and lead author on the paper.

“At that point, it is very unlikely for them to bounce back.”

Emperor penguins live and die by sea ice, which is where they breed and molt. The animals build their colonies on spans of ice that satisfy very specific conditions: it must be locked to the Antarctic shoreline but close to open seawater (giving the birds access to food). Climate heating is melting sea ice, however, which effectively destroys the birds’ habitat, food access, and ability to reproduce.

For their study, the team combined a global climate model (created by the National Center for Atmospheric Research, NCAR) and a model of the penguin populations themselves. The first gave the team a rough idea of how sea ice will evolve in the future, especially in terms of where and when it will form or melt in the future. The second one worked to predict how colonies might react to the changes in their environment.

“We’ve been developing that penguin model for 10 years,” says Jenouvrier. “It can give a very detailed account of how sea ice affects the life cycle of emperor penguins, their reproduction, and their mortality. When we feed the results of the NCAR climate model into it, we can start to see how different global temperature targets may affect the emperor penguin population as a whole.”

The compound model was then used to examine three different scenarios. The first assumes an increase in global average temperatures of only 1.5 degrees Celsius (the goal set out by the Paris climate accord). The second involves a temperature increase of 2 degrees Celsius. The final scenario assumes no action was taken against climate change, leading to temperature increases of 5 to 6 degrees Celsius.

The first one led to a loss of around 5% of sea ice by 2100, causing a roughly 20% drop in the penguin population. The 2-degree warming scenario led to around 15% ice loss and a 30% drop in penguin numbers. The business as usual scenario was by far the most damaging, leading to almost complete loss of the penguin colonies.

“Under that scenario, the penguins will effectively be marching towards extinction over the next century,” she says.

The paper “The Paris Agreement objectives will likely halt future declines of emperor penguins” has been published in the journal Global Change Biology.

The last mammoths lived on a remote island in the Arctic

The last woolly mammoths lived on Wrangel Island in the Arctic Ocean, a new study reports.

Exhibit at the Royal BC Museum in Victoria (Canada).

An international team of researchers with members from the Universities of Helsinki, the University of Tübingen, and the Russian Academy of Sciences reports that the wooly mammoths likely went extinct due to a combination of habitat isolation and extreme weather events — as well as the spread of ancient humans.

Within a very short timeframe some 4,000 years old, the last population of these animals — which lived on Wrangel Island — went extinct, they add.

Last of the mammoths

“It’s easy to imagine that the population, perhaps already weakened by genetic deterioration and drinking water quality issues could have succumbed after something like an extreme weather event,” says professor Hervé Bocherens from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen, a co-author of the study.

Mammoths enjoyed great success during the last ice age, from around 100,000 to 15,000 years ago. The species ranged from Spain to Alaska and fared quite comfortably during that time. Around 15,000 years ago, however, temperatures started picking up, and the mammoths’ natural range started to shrink. The Wrangel Island population, the team notes, was cut off by rising sea levels from their mainland counterparts and would live in isolation for the next 7,000 years.

The team examined carbon, nitrogen, sulfur, and strontium isotopes from a large set of mammoth bones and teeth dug up from Northern Siberia, Alaska, the Yukon, and Wrangel Island. These specimens ranged in age from 40,000 to 4,000 years ago. The researchers aimed to document possible changes in the mammoths’ diets over this time (which would be ‘recorded’ in their bones as different isotope ratios) as proxies for the environmental disturbances the species was exposed to.

The results showed that the carbon and nitrogen isotope ratios in the collagen of Wrangel Island mammoths did not shift as the climate warmed up some 10,000 years ago. The values remained unchanged until the mammoths disappeared, seemingly from the midst of stable, favorable living conditions.

Such results show a stark contrast with those obtained from wooly mammoth bones in the Ukrainian-Russian plains, who died out 15,000 years ago. It’s also different from the mammoths of St. Paul Island in Alaska, who disappeared 5,600 years ago. In both cases, the last representatives of these populations (that we’ve found) show markedly-different isotope compositions, suggesting changes in their environment shortly before they became locally extinct.

Earlier research had shown that mammoths on Wrangel Island suffered certain mutations that affected their fat metabolism. In the present study, the team reports finding a different ratio of carbon isotopes in their bones compared to Siberian mammoths, likely due to a difference in the fat and carbohydrates in the diets of the two groups.

The bones of Wrangel Island mammoths also showed higher levels of sulfur and strontium, likely due to increased weathering of bedrock in the area close to the mammoths’ extinction. These elements likely found their way into rivers and streams, affecting the quality of the animals’ drinking water.

All in all, the mammoths of the island disappeared suddenly, but perhaps, not dramatically. The team says short-term events like extreme weather is what likely did them in in the end. A simple icing event can cover the ground in a thick enough layer of ice to prevent the animals from finding food — which is enough to cause a dramatic drop in numbers. Another possible reason is the spread of humans in the area, with the earliest evidence of their presence on the island preceding the last mammoth fossils by just a few hundred years. The chance of finding evidence that humans hunted Wrangel Island mammoths is very small, the team explains, yet a human contribution to the extinction cannot be ruled out.

The study shows just how fragile a small population of large mammals is to environmental shifts and human activity. The team says their findings can help preserve species by aiming conservation efforts at the populations that are not isolated from one another.

The paper “Thriving or surviving? The isotopic record of the Wrangel Island woolly mammoth population” has been published in the journal Quaternary Science Reviews.

Pixelated images showcase how close these species are to extinction

As a campaign the World Wildlife Fund ran in 2008 is re-making the rounds on reddit, one Imgur user has created a powerful follow-up.

Image credits JJSmooth44 / Imgur.

Back in 2008, the World Wildlife Fund (WWF) released a striking photo campaign. Called WWF Japan – Population by pixel, the campaign was created by the agency Hakuhodo C&D in Tokyo. It consisted of a set of 4 posters, blurred so that every single pixel in the photo corresponds to one living animal — the poorer-quality the final image is, the worse for wear the species is in the wild.

Since 2008, however, the four species shown in the campaign have been recovering and increasing in numbers in the wild. But those four aren’t the only ones that have been struggling. A collection of 22 new but very similar images recently published on Reddit by user JJSmooth44 showcases just that.

JJSmooth44 claims he “did it as a programming challenge,” using the Python language to obscure these images through pixelation, matching the number of pixels with the number of individuals that species are estimated to still have in the wild. He took the original photos from the Animal Planet endangered animals list.

“The code is very gross,” he says. “I only worried about the final product and not the readability/niceness of the code.”

The rate of species extinction has been picking up recently, and a big part of that is due to us. Species do go extinct through natural mechanisms, but more and more of them are struggling to adapt to ever-more pollution, human encroachment, and habitat devastation. Climate warming is further pushing these species towards extinction.

Work such as the Population by Pixels campaign and JJSmooth44’s work perfectly showcase how vulnerable Earth’s species and ecosystems can be if we do not care for them. Just like a picture losing its pixels, these species run a very real danger of fading away forever.

Kea parrot.

Human-driven extinction cost New Zealand 50 million years’ worth of bird evolution

The arrival of humans definitely wasn’t the most fortunate thing to ever happen to New Zealand.

Kea parrot.

Kea parrot, an endangered species that’s native to New Zealand.
Image via Pixabay.

New research shows that half of the island’s bird species have gone extinct since humans arrived. The team estimates it would take approximately 50 million years to recover the same number of bird species.

Gone with the dodo

“The conservation decisions we make today will have repercussions for millions of years to come,” says Luis Valente of Museum für Naturkunde in Berlin and the paper’s lead author.

“Some people believe that if you leave nature alone it will quickly recuperate, but the reality is that, at least in New Zealand, nature would need several million years to recover from human actions — and perhaps will never really recover.”

While the number of lost or threatened bird species often has been quantified, the team explains, the broad-scale evolutionary consequences of human impact on island biodiversity rarely have been measured.

Valente says that the biodiversity levels observed today are the result of millions of years of evolutionary time, and that extinctions caused by humans erase this history. So, for their new study, the team developed a new method to estimate how long it would take for a particular closed ecosystem (i.e. island) to regain the species it lost to human activity.

New Zealand happened to be an ideal case to apply and demonstrate this new method, spawning the present study.

“The anthropogenic wave of extinction in New Zealand is very well documented, due to decades of paleontological and archaeological research,” Valente says.

“Also, previous studies have produced dozens of DNA sequences for extinct New Zealand birds, which were essential to build datasets needed to apply our method.”

The team used computer models to simulate a range of human-induced extinction scenarios and see how the ecosystem fared following these.  All in all, they report that it would take approximately 50 million years to recover the number of species lost since humans first arrived in New Zealand.

If all species currently under threat are allowed to go extinct, they add, it would require about 10 million years of evolutionary time to return to the numbers of species today. However, not all is lost.

“The conservation initiatives currently being undertaken in New Zealand are highly innovative and appear to be efficient and may yet prevent millions of years of evolution from further being lost,” Valente says.

In the future, the team plans to estimate evolutionary return times for several other islands worldwide and see if any risk losing more evolutionary time. They also want to find out which anthropogenic factors play the most significant role in determining those losses.

The paper “Deep Macroevolutionary Impact of Humans on New Zealand’s Unique Avifauna” has been published in the journal Current Biology.

8 bird species have disappeared this decade or are on the brink of extinction

Credit: Cinemablend.

Unlike the animation Rio, in real life, there are no more Spix’s Macaws left in the wild. Credit: Cinema Blend.

In the 2011 animation film Rio, a captive-raised Spix’s Macaw by the name of Blu arrives in Brazil to mate with the last-known wild member of his species, a female named Jewel. In real life, however, Rio would have arrived a decade too late.

According to a recent study, the last wild Spix’s Macaw disappeared in 2000 and the species is now presumed extinct apart from a handful of specimens born and raised in captivity. Along with it are seven other bird species that have suffered the same fate in the last decade.

The study, funded by the non-profit BirdLife International, statistically analyzed 51 critically endangered bird species and found that eight could likely be classified as extinct or very close to extinction. Specifically, three are already extinct, one is extinct in the wild — there are an estimated 70 Spix’s Macaws (Cyanopsitta spixii), left in the world, all captive — and four are extremely close to extinction, if not already gone.

The extinct bird species identified in the new study are the Brazilian cryptic tree hunter (Cichlocolaptes mazarbarnetti), last seen in 2007; the Brazilian alagoas foliage-gleaner (Philydor novaesi), last seen in 2011; and the Hawaiian black-faced honeycreeper (Melamprosops phaeosoma), last seen in 2004.

A total of 187 species of birds have gone extinct since scientists started keeping records. Historically, birds native to islands have been the most vulnerable due to invasive species, but deforestation ramped by expanding agriculture and logging is growing fast as the leading driver of avian extinction.

“Ninety percent of bird extinctions in recent centuries have been of species on islands,” said Dr. Stuart Butchart, BirdLife’s Chief Scientist and lead author on the paper. “However, our results confirm that there is a growing wave of extinctions sweeping across the continents, driven mainly by habitat loss and degradation from unsustainable agriculture and logging”.

Adult Spix's macaw in Vogelpark Walsrode, Germany in 1980. Credit: Wikimedia Commons.

Adult Spix’s macaw in Vogelpark Walsrode, Germany in 1980. Credit: Wikimedia Commons.

Butchart and colleagues hope that their work will inspire more action to prevent other extinctions. Five of the eight extinctions reported in the journal Biological Conservation involve species in South America, four of which happened in Brazil. The Amazon, where most of these extinct species were once abundant, lost 17 million hectares of forest between 2001 and 2012. Unlike other animals, birds are more vulnerable to habitat loss because they often occupy ecological niches, consuming specific prey and nesting in specific trees.

“Our results confirm that there is a growing wave of extinctions sweeping across the continents, driven mainly by habitat loss and degradation from unsustainable agriculture and logging,” said Butchart.