Extinction of Woolly rhinoceros (Coelodonta Antiquitatis) This species, which lived at the beginning of the Holocene Epoch, remains shrouded in mystery, with conflicting evidence as to its causes and dynamics. A team of paleontologists led by scientists from the University of Adelaide and the University of Copenhagen has used computationally intensive modelling techniques and extensive paleontological and ancient DNA information to uncover why and how this enigmatic species went extinct.
Woolly rhinoceros (Coelodonta Antiquitatis) was once widespread across northern and central Eurasia but became extinct about 10,000 years ago. Image by Mauricio Antón.
The woolly rhinoceros is an iconic member of the giant steppe fauna of central and northern Eurasia, originating from the Tibetan Plateau approximately 2.5 million years ago.
It is a cold-adapted species with thick skin and long fur, and its body size is comparable to that of modern mammals. African white rhinoceros (Ceratotherium simum).
Based on fossil chronology, the woolly rhino is estimated to have become extinct by 13,900 years ago, despite having survived multiple glacial and interglacial cycles during the Pleistocene.
However, recent discovery of woolly rhinoceros DNA in early Holocene deposits suggests a later extinction date of 9,800 years ago. This young dating is subject to debate, but is unlikely to be due to redeposition of DNA.
“Using computer models, fossils and ancient DNA, we have traced the population history of woolly rhinoceros across Eurasia over 52,000 years, at a resolution previously thought impossible,” said Dr Damian Fordham, from the University of Adelaide.
“This suggests that a combination of decreasing temperatures beginning 30,000 years ago and small-scale but continuing hunting by humans caused the woolly rhino's range to shrink southwards, confining it to isolated and rapidly degraded habitat at the end of the last ice age.”
“As the Earth thawed and temperatures rose, woolly rhino populations were unable to colonize key new habitats in northern Eurasia, causing destabilization and collapse, ultimately leading to extinction.”
The new research contradicts previous studies that found humans were not responsible for the woolly rhino's extinction, despite the animal coexisting with humans for tens of thousands of years before its disappearance.
“The demographic responses revealed by our analysis have a much higher resolution than previously captured in genetic studies,” said Professor Eline Lorenzen from the University of Copenhagen.
“This allowed us to pinpoint key interactions between woolly rhinos and humans and document how these have changed over time and space.”
“One of these largely overlooked interactions is persistent, low-level hunting by humans, presumably for food.”
“Humans pose similar environmental threats today,” the researchers said.
“Large animal populations have been forced into fragmented and suboptimal habitats by overhunting and changes in human land use.”
“Of the 61 species of large terrestrial herbivores weighing more than one tonne that lived during the Late Pleistocene, only eight survive today, five of which are rhinos.”
“Our results show how climate change and human activities can lead to the extinction of large animals,” said Professor David Nogus Brabo from the University of Copenhagen.
“This understanding is crucial for developing conservation strategies to protect species currently at risk of extinction, such as vulnerable rhinos in Africa and Asia.”
“Studying past extinctions can provide valuable lessons for conserving Earth's remaining large animals.”
of study Appeared in Proceedings of the National Academy of Sciences.
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Damien A. Fordham others2024. 52,000 years of woolly rhino population dynamics reveal mechanisms of extinction. PNAS 121(24):e2316419121; doi:10.1073/pnas.2316419121
Source: www.sci.news
