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It did not look much like the delicate unicorns of myth and legend, but the extinct unicorn of Siberia is even more appealing to paleontologists.
For the first time, scientists analyzed his DNA – and realized that everyone was wrong about the mysterious beast.
The ancient rhinos did not die 200,000 years ago, before the last ice age – as we had previously thought. Strange animals have survived much, much longer, disappearing only 36,000 years ago. In fact, they could have lived alongside modern humans.
Moreover, as it was thought, the Siberian unicorn was not closely related to modern rhinos, but to a single lineage that separated from the lineage that led to modern rhinos over 40 million years ago. .
Until now, our knowledge of the unicorn (Elasmotherium sibiricum) was blocked due to lack of fossil data.
Only a few fragmented bones were recovered and, apart from the size of the beast (about 3.5 tons), the same range as that of a small African elephant was difficult to analyze.
For example, part of the skull described in a 2016 article was radiocarbon dated 29,000 years ago, but the result was considered unreliable.
An international team of researchers collected 23 specimens of Siberian unicorn bones and submitted them to radiocarbon dating to determine if they could recover DNA and learn more about the unicorn. of Siberia and its time on Earth.
The results were surprising: they have been dated several times after the animals were thought to be extinct, the most recent dating from 35,000 to 36,000 years ago. At that time, humans began to populate the steppes of Russia, Kazakhstan, Mongolia and northern China.
But humans probably have nothing to do with the disappearance of the animal.
"If we look at timing, it's during a period of climate change, which was not extreme, but which caused a whole series of colder winters that we believe actually has changed the extent of the grasslands in the region, "said Alan Cooper, of the Australian Center for Early DNA at Adelaide University explained to ScienceAlert.
"We can also see the change in isotopes in the bones of animals – you can see and measure the carbon and nitrogen in the bones and we can see that it was only about eating from the grass. "
At about the same time, other grass-eating animals began to change their diet into grasses, shrubs, and other vegetation where they could bite, but not the Siberian unicorn. The researchers believe that the poisoned permafrost has killed him.
"It looks like this unicorn was so specialized to eat grass that it could not survive," Cooper said.
"His head was huge, his waist was really very low, sitting very low, so he did not need to lift his head.It may be wondered if he could even lift it at all. highly specialized and once the environment has changed, it seems to be off. "
We do not know how much the horn of the animal has grown because it has never been found. However, the part of the skull where the horn would have grown was found, with an absolutely massive base. On the basis of comparisons with live horned animals, the horn of a Siberian unicorn could have measured up to 1 meter long.
Combined with its big heavy head, this horn could have made the foliage attack even more difficult for the old rhinoceros. But if his lineage was tens of millions of years old, the species had already survived several climate changes.
Exactly, why this relatively mild cooling event was the last straw on the unicorn is still a mystery, and more research is needed to solve it. But this is a warning that we would do well to take into account.
"What's worrying is that it shows that it's not necessary to deal with a major climate change so that vegetation can destroy a species – and that's before that humans have limited the range of animals, can you imagine what will happen today? " Cooper said.
"That's why people are interested in large grasslands such as Africa. But what about food production? These kinds of things, once climate change has started to happen, the environment can have quite a big impact quickly. "
The team's research was published in the journal Nature Ecology & Evolution.
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