scientists – Eastern European Association of the Greens

Mouse thought extinct for 150 years found living on island

06/29/2021 News

(CNN) – A mouse thought to have become extinct more than 150 years ago has been found alive on an island off the coast of Western Australia, researchers have discovered.

Scientists compared DNA samples from eight extinct Australian rodents and 42 of their living relatives, and discovered that the extinct Gould’s mouse was “indistinguishable” from the Shark Bay mouse.

Researchers were studying the decline of the country’s native species since the arrival of Europeans in Australia in 1788.

The mouse — which will still be known by the common name “djoongari,” or “Shark Bay mouse” — was once found across the country, from south-west Western Australia to New South Wales, but was last seen in 1857. The introduction of invasive species, agricultural land clearing and new diseases destroyed the native species, researchers said, adding that climate change and poor fire management also affected population sizes.

The remaining populations of the djoongari were located on a single 42 square-kilometer (16.2 square-mile) island in Shark Bay, Bernier Island. One small population is not enough for a species to survive, researchers said, so the mice have been taken to two other islands to establish new populations.

“The resurrection of this species brings good news in the face of the disproportionally high rate of native rodent extinction, making up 41 per cent of Australian mammal extinction since European colonisation in 1788,” lead author Emily Roycroft, an evolutionary biologist from the Australian National University (ANU), said in a statement.

“It is exciting that Gould’s mouse is still around, but its disappearance from the mainland highlights how quickly this species went from being distributed across most of Australia, to only surviving on offshore islands in Western Australia. It’s a huge population collapse,” she added.

The team also studied seven other extinct native species, which were found to have high genetic diversity immediately before extinction, showing that their populations were widespread before Europeans arrived.

“This shows genetic diversity does not provide guaranteed insurance against extinction,” Roycroft warned.

More than 80% of Australia’s mammals are endemic, as result of Australia’s long period of isolation from other continents. But the country has what researchers described in a 2015 paper as an “extraordinary rate of extinction.” Meanwhile, a study published in 2019 found that Australia was home to 6-10% of the world’s post-1500 recognized extinctions.

Roycroft said the extinction of the seven native species happened “very quickly.”

Humans have already wiped out hundreds of species and pushed many more to the brink of extinction through wildlife trade, pollution, habitat loss and the use of toxic substances. The Earth’s sixth mass extinction is happening now, much faster than previously expected — and the rate at which species are dying out has accelerated in recent decades, scientists have warned.

The research will be published in the journal PNAS next month.

Scientists has found a new human species – “Dragon Man”

06/28/2021 News

(CNN) – A cranium hidden at the bottom of a well in northeastern China for more than 80 years may belong to a new species of early human that researchers have called “dragon man.”

The exciting discovery is the latest addition to a human family tree that is rapidly growing and shifting, thanks to new fossil finds and analysis of ancient DNA preserved in teeth, bones and cave dirt.

The well-preserved skullcap,found in the Chinese city of Harbin, is between 138,000 and 309,000 years old, according to geochemical analysis, and it combines primitive features, such as a broad nose and low brow and braincase, with those that are more similar to Homo sapiens, including flat and delicate cheekbones.

The ancient hominin — which researchers said was “probably” a 50-year-old man — would have had an “extremely wide” face, deep eyes with large eye sockets, big teeth and a brain similar in size to modern humans.

Three papers detailing the find were published in the journal The Innovation on Friday.

“The Harbin skull is the most important fossil I’ve seen in 50 years. It shows how important East Asia and China is in telling the human story,” said Chris Stringer, research leader in human origins at The Natural History Museum in London and coauthor of the research.

Researchers named the new hominin Homo longi, which is derived from Heilongjiang, or Black Dragon River, the province where the cranium was found.

The team plans to see if it’s possible to extract ancient proteins or DNA from the cranium, which included one tooth, and will begin a more detailed study of the skull’s interior, looking at sinusesand both ear and brain shape, using CT scans.

Dragon man’s large size could be an adaptation to the harsh environment in which he likely lived, researchers said.

We are family

It’s easy to think of Homo sapiens as unique, but there was a time when we weren’t the only humans on the block.

In the millennia since Homo sapiens first emerged in Africa about 300,000 years ago, we have shared the planet with Neanderthals, the enigmatic Denisovans, the “hobbit” Homo floresiensis, Homo luzonensis and Homo naledi, as well as several other ancient hominins. We had sex with some of them and produced babies. Some of these ancestors are well represented in the fossil record, but most of what we know about Denisovans comes from genetic information in our DNA.

The story of human evolution is changing all the time in what is a particularly exciting period for paleoanthropology, Stringer said.

The announcement of dragon man’s discovery comes a day after a different group researchers published a paper in the journal Science on fossils found in Israel, which they said also could represent another new type of early human.

The jaw bone and skull fragment suggested a group of people lived in the Middle East 120,000 to 420,000 years ago with anatomical features more primitive than early modern humans and Neanderthals.

While the team of researchers stopped short of calling the group a new hominin species based on the fossil fragments they studied, they said the fossils resembled pre-Neanderthal human populations in Europe and challenged the view that Neanderthals originated there.

“This is a complicated story, but what we are learning is that the interactions between different human species in the past were much more convoluted than we had previously appreciated,” Rolf Quam, a professor of anthropology at Binghamton University and a coauthor of the study on the Israeli fossils, said in a news release.

Stringer, who was not involved in the Science research, said the fossils were less complete than the Harbin skull, but it was definitely plausible that different types of humans co-existed in the Levant, which was a geographical crossroads between Africa, Asia and Europe that today includes Lebanon, Syria, Iraq, Israel, Jordan and other countries in the Middle East.

Two fossils found in Israel challenge the idea that Neanderthals originated in Europe.

Concealed treasure

The Harbin cranium was discovered in 1933 by an anonymous Chinese man when a bridge was built over the Songhua River in Harbin, according to one of the studies in The Innovation. At the time, that part of China was under Japanese occupation, and the man who found it took it home and stored it at the bottom of a well for safekeeping.

“Instead of passing the cranium to his Japanese boss, he buried it in an abandoned well, a traditional Chinese method of concealing treasures,” according to the study.

After the war, the man returned to farming during a tumultuous time in Chinese history and never re-excavated his treasure. The skull remained unknown to science for decades, surviving the Japanese invasion,civil war, the Cultural Revolution and, more recently, rampant commercial fossil trading in China, the researchers said.

The third generation of the man’s family only learned about his secret discovery before his death and recovered the fossil from the well in 2018. Qiang Ji, one of the authors of the research, heard about the skull and convinced the family to donate it to the Geoscience Museum of Hebei GEO University.

‘Sister lineage’

The so-called dragon man likely belonged to a lineage that may be our closest relatives, even more closely related to us than Neanderthals, the study found. His large size and where the fossil was found, in one of China’s coldest places, could mean the species had adapted to harsh environments. Dragon man had a large brain, deep set eyes, thick brow ridges, a wide mouth and oversize teeth.

“We are human beings. It is always a fascinating question about where we were from and how we evolved,” said coauthor Xijun Ni, a research professor at the Chinese Academy of Sciences and the vice director of the Key Laboratory of Vertebrate Evolution and Human Origins.

“We found our long-lost sister lineage.”

The study suggested that other puzzling Chinese fossils that paleoanthropologists have found hard to classify — such as those found in Dali in Yunnan in southwestern China and a jawbone from the Tibetan plateau, thought by some to be Denisovan — could belong to the Homo longi species.

Stringer said also it was definitely plausible that dragon man could be a representative of Denisovans, a little-known and enigmatic human population that hasn’t yet been officially classified as a hominin species according to taxonomic rules.

They are named after a Siberian cave where the only definitive Denisovan bone fragments have been found, but genetic evidence from modern human DNA suggests they once lived throughout Asia.

Denisovans is a general name, Stringer said, and they haven’t officially been recognized as a new species — in part because the five Denisovan fossils that exist are so tiny they don’t fulfill the requirements for a “designated type specimen” that would make it a name-bearing representative.

Denisovans and Homo longi both had large, similar molars, the study noted, but, given the small number of fossils available for comparison, it was impossible to say for sure, said Ni, who hoped that DNA experiments might reveal whether they are the same species.

“We’ve only just begun what will be years of studying this fascinating fossil,” Stringer said.

Biodiversity loss and climate change are similar to each other and should be talked together

06/11/2021 News

Biodiversity loss has been eclipsed by climate change on the global agenda but the two issues are closely linked, have similar impacts on human welfare and need to be tackled urgently, together, scientists said on Thursday, Reuters informs.

The destruction of forests and other ecosystems undermines nature’s ability to regulate greenhouse gases in the atmosphere and protect against extreme weather impacts – accelerating climate change and increasing vulnerability to it, a report by the U.N. agencies on climate change and biodiversity said.

The rapid vanishing of carbon-trapping mangroves and seagrasses, for example, both prevents carbon storage and exposes coastlines to storm surges and erosion.

The report calls for governments to enact policies and nature-based solutions to address both issues.

“For far too long, policymakers tended to see climate change and biodiversity loss as separate issues, so policy responses have been siloed,” said report co-author Pamela McElwee, an ecologist at Rutgers University, told a virtual news conference.

“Climate has simply gotten more attention because people are increasingly feeling it in their own lives – whether it’s wildfires or hurricane risk. Our report points out that biodiversity loss has that similar effect on human wellbeing.”

The report marks the first collaboration of scientists from both the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the Intergovernmental Panel on Climate Change (IPCC).

Calling on countries to protect entire ecosystems rather than iconic locations or species, the report’s authors hope to influence policy discussions at both the U.N. conference on biodiversity in October in Kunming, China, and at the U.N. climate talks being held a month later in Glasgow, Scotland.

“The report will connect the two COPs (summits) in terms of thinking,” said Hans Poertner, IPCC co-chair.

Ahead of the Kunming conference, the U.N. has urged countries to commit to protecting 30% of their land and sea territories by 2030. Experts say at least 30% of the Earth, if not 50%, should be under conservation to maintain habitats under a changing climate.

So far more than 50 countries, including the United States, have made the 30% pledge.

“With this report, the two issues are married now, which is really powerful,” said James Hardcastle, a conservationist at the International Union for Conservation of Nature (IUCN). “We can use the momentum to get more commitments from countries on conservation.”

Since 2010, countries have collectively managed to add almost 21 million square kilometers – an area the size of Russia – to the global network of protected lands, bringing the current total to nearly 17% of the Earth’s landmass, according to a report published last month by the IUCN.

Yet less than 8% of these lands are connected – something considered crucial for ecological processes and the safe movement of wildlife. Meanwhile, total marine conservation areas lag at 7%, below the 2020 target of 10%.