An ancient leg bone found next to the famous Toumai skull of a human ancestor provides new evidence that our ancestors could walk upright as early as 7 million years ago, Science reports..

Part of a femur and two forearm bones from the Jurab Desert in Chad suggest a hominid species known as the Chadian sahelanthropus (Sahelanthropus tchadensis) walked bipedally and also spent some time in trees, according to a new study..

[see_also ids\u003d"

If this creature really walked on two legs, it's a huge discovery, says Dan Lieberman, a paleoanthropologist at Harvard University.. This would mean that bipedalism was one of the first features of the human ancestry, which split off from the chimpanzee around this time, he says.. But according to Lieberman, a “bad throw” is possible because the fossil femur is missing both ends..

Sahelanthropus first became known to the world when researchers discovered its nearly intact skull in 2001.. Paleontologist Michel Brunet from the University of Poitiers (France) named this creature Tumai, which in the local Daza language means "

The skull was larger than that of a modern chimpanzee.. But his teeth told a different story: fangs resembled those of later hominids or members of the human family.. The shape of the opening at the base of the skull—the foramen magnum—suggested that Sahelanthropus balanced its head on an upright neck, similar to upright primates such as modern humans..

But the skull alone cannot prove that the species walked straight. Needed legs.. And as it turns out, Toumai had one, but her Brunet team failed to identify.

In 2004, Aude Bergeret, then a master's student at Poitiers, noticed a femur shaft and forearm bones in a box full of animal fossils labeled " She alerted her consultant, who determined it was a primate femur, and turned to Brune, Tumai's discoverer.. But Brunet's team never did a serious analysis..

Only in 2017 did the bone specialist Guillaume Daver begin studying the student's find together with the paleoanthropologist Franck Guy of Poitiers..

In a new study, a team of French and Chadian researchers used a suite of techniques to analyze the internal and external structure of bones.. When they compared these features and sizes with living and fossil apes and hominins (humans), they found that the orientation of the base of the femoral neck and the flattening of the top of the bone resembled those of hominins, members of the human race, but certainly not the femurs of African apes.. In addition, bone density seen in cross section was within the hominin range, suggesting that it was subjected to loading compatible with upright posture..

There was no one " According to him, it was " If this is true, then this Toomai walked right through the forests that bordered the ancient Lake Chad, more than 1 million years earlier than the earliest known bipedal hominids - Orrorin tugenensis and Ardipithecus.

Even if Sahelanthropus was bipedal, he still spent quite a lot of time in the trees.. Two forearm bones show that this species also had an arboreal lifestyle, where it was likely to be safer from predators..

However, experts say more work is needed to show that Sahelanthropus was indeed an upright human ancestor.. “Evidence is compatible with bipedalism,” but doesn’t prove it, says functional morphologist Chris Ruff of Johns Hopkins University (Maryland, USA).

Others believe that the bones are so similar to chimpanzees that it is unlikely that the species walked upright like later hominids.. It was not a chimpanzee, but "

And yet, the femur shaft taunts scientists - it dates back to a time when our earliest ancestors were very similar to African apes, but had already moved away from the line leading to chimpanzees..

“At some point, hominids become bipedal, but exactly how and when this transition occurred is one of the most interesting and important questions regarding our origins,” says paleoanthropologist Carol Ward from the University of Missouri, Columbia, USA.. “Any fossils that talk about it are really important”. But, unfortunately, in her opinion, they do not provide convincing information..

In addition to the transition to upright posture, one of the most important evolutionary leaps from still apes to already humans was the emergence of cooking and the transition of the human ancestor to softer foods.. It did not require powerful jaw muscles and huge teeth, as well as the need to chew almost constantly.. This significantly reduced the time for meals for the human ancestor, made food more high-calorie and gave more time to think..

And it also allowed the cranium to grow, which could accommodate the brain that grew in the course of evolution..

[see_also ids\u003d"

Sahelanthropus (Sahelanthropus is a genus of hominins whose representatives lived in the late Miocene. In the genus, one species is distinguished - Chadian sahelanthropus (Sahelanthropus tchadensis). Described based on finds made in the north-west of the Republic of Chad in 2001: the skull of Tumai and fragments of several more individuals.