Jan 3, 2026 06:30 PM
Anthropologists offer new evidence of bipedalism in long-debated fossil discovery
https://www.eurekalert.org/news-releases/1109959
EXCERPTS: In recent decades, scientists have debated whether a seven-million-year-old fossil was bipedal -- a trait that would make it the oldest human ancestor. A new analysis by a team of anthropologists offers powerful evidence that [b]Sahelanthropus tchadensis -- a species discovered in the early 2000s -- was indeed bipedal by uncovering a feature found only in bipedal hominins.
Using 3D technology and other methods, the team identified Sahelanthropus’s femoral tubercle, which is the point of attachment for the largest and most powerful ligament in the human body -- the iliofemoral ligament -- and vital for walking upright. The analysis also confirmed the presence of other traits in Sahelanthropus that are linked to bipedalism.
“Sahelanthropus tchadensis was essentially a bipedal ape that possessed a chimpanzee-sized brain and likely spent a significant portion of its time in trees, foraging and seeking safety,” says Scott Williams, an associate professor in New York University’s Department of Anthropology who led the research. “Despite its superficial appearance, Sahelanthropus was adapted to using bipedal posture and movement on the ground.”
The study, which included researchers from the University of Washington, Chaffey College, and the University of Chicago, appears in the journal Science Advances.
[...] The authors also found that Sahelanthropus had a relatively long femur relative to its ulna -- additional evidence of bipedalism. The researchers note that apes have long arms and short legs, whereas hominins have relatively long legs. And while Sahelanthropus had much shorter legs than do modern humans, these were distinct from apes and approached Australopithecus in relative femur length, suggesting another adaptation to bipedalism.
“Our analysis of these fossils offers direct evident that Sahelanthropus tchadensis could walk on two legs, demonstrating that bipedalism evolved early in our lineage and from an ancestor that looked most similar to today’s chimpanzees and bonobos,” concludes Williams... (MORE - missing details)
https://www.eurekalert.org/news-releases/1109959
EXCERPTS: In recent decades, scientists have debated whether a seven-million-year-old fossil was bipedal -- a trait that would make it the oldest human ancestor. A new analysis by a team of anthropologists offers powerful evidence that [b]Sahelanthropus tchadensis -- a species discovered in the early 2000s -- was indeed bipedal by uncovering a feature found only in bipedal hominins.
Using 3D technology and other methods, the team identified Sahelanthropus’s femoral tubercle, which is the point of attachment for the largest and most powerful ligament in the human body -- the iliofemoral ligament -- and vital for walking upright. The analysis also confirmed the presence of other traits in Sahelanthropus that are linked to bipedalism.
“Sahelanthropus tchadensis was essentially a bipedal ape that possessed a chimpanzee-sized brain and likely spent a significant portion of its time in trees, foraging and seeking safety,” says Scott Williams, an associate professor in New York University’s Department of Anthropology who led the research. “Despite its superficial appearance, Sahelanthropus was adapted to using bipedal posture and movement on the ground.”
The study, which included researchers from the University of Washington, Chaffey College, and the University of Chicago, appears in the journal Science Advances.
[...] The authors also found that Sahelanthropus had a relatively long femur relative to its ulna -- additional evidence of bipedalism. The researchers note that apes have long arms and short legs, whereas hominins have relatively long legs. And while Sahelanthropus had much shorter legs than do modern humans, these were distinct from apes and approached Australopithecus in relative femur length, suggesting another adaptation to bipedalism.
“Our analysis of these fossils offers direct evident that Sahelanthropus tchadensis could walk on two legs, demonstrating that bipedalism evolved early in our lineage and from an ancestor that looked most similar to today’s chimpanzees and bonobos,” concludes Williams... (MORE - missing details)