Walking on Two Legs: The Oldest Human Ancestor Uncovered

A recent study has shed new light on the ancient species Sahelanthropus tchadensis, suggesting it might be the oldest known human ancestor. This species, found in Chad's Djurab desert in the early 2000s, has been a topic of debate among scientists. The big question was whether it walked on two legs, a key trait of human ancestors. Researchers used advanced 3D technology to examine the fossils. They found a special feature called the femoral tubercle, which is crucial for walking upright. This discovery supports the idea that Sahelanthropus was indeed bipedal. The study also revealed other traits linked to bipedalism, such as a longer femur compared to its ulna, similar to early human ancestors like Australopithecus.The team also found that Sahelanthropus had a natural twist in its femur, helping it to walk with its legs pointing forward. Additionally, it had gluteal muscles similar to those in early hominins, which aid in standing, walking, and running. These findings confirm that bipedalism evolved early in our lineage, possibly from an ancestor similar to modern chimpanzees and bonobos. The study, published in Science Advances, provides strong evidence that Sahelanthropus was a bipedal ape with a chimpanzee-sized brain. It likely spent a lot of time in trees, but was also adapted to walking on the ground. This discovery challenges previous assumptions and offers a deeper understanding of human evolution.