Latest News
Human time-line keeps moving back
Mar 20
Images show aerial and lateral images of (top to bottom) (A) a human footprint made walking normally with an extended knee and hip gait; (B) a human footprint made walking with bent-knees and hips to mimic a chimpanzee; and (C) a scan of a cast from the Laetoli fossil trackway. Notice that the toe is much deeper than the heel in the middle print and that the Laetoli scan looks more like the human print. (Credit: Randy Haas, University of Arizona)
When one reads Genesis 1: 26-27 it is clear that humans did not evolve from some common ancestor of chimpanzees. For that reason, it is no surprise that the timeline for humans (in evolutionary circles) gets pushed further back.
David Raichlen, an assistant professor in the University of Arizona School of Anthropology, and his colleagues at the University at Albany and City University of New York's Lehman College have developed new experimental evidence indicating that early hominins were walking with a human-like striding gait supossively 3.6 million years ago.
Since the Laetoli tracks were discovered, scientists have debated whether they indicate a modern human-like mode of striding bipedalism, or a less-efficient type of crouched bipedalism more characteristic of chimpanzees whose knees and hips are bent when walking on two legs.
To resolve this, Raichlen and his colleagues devised the first biomechanical experiment explicitly designed to address this question. The team built a sand trackway in Raichlen's motion capture lab at the UA and filmed human subjects walking across the sand. The subjects walked both with normal, erect human gaits and then with crouched, chimpanzee-like gaits. Three-dimensional models of the footprints were collected by biological anthropologist Adam Gordon using equipment brought from his Primate Evolutionary Morphology Laboratory at the University at Albany.
The researchers examined the relative depth of footprints at the heel and toe, and found that depths are about equal when made by a person walking with an erect gait. In contrast, the toe print is much deeper than the heel print when produced by a crouched gait, a product of the timing of weight transfer over the length of the foot.
"We expected that the Laetoli footprints would resemble those of someone walking with a bent knee, bent hip gait typical of chimpanzees, and not the striding gait normally used by modern humans," Raichlen said. "But to our surprise, the Laetoli footprints fall completely within the range of normal human footprints."
The fossil footprints at Laetoli preserve a remarkably even depth at the toe and heel, just like those of modern humans. "This more human-like form of walking is incredibly energetically efficient" Raichlen said.
Note: If it looks like a human foot print and walks like a human, perhaps (just maybe) it is a human.
Humans pushed back even further:
A shape comparison of the most complete fossil femur indicates the earliest form of bipedalism occurred at least six million years ago and persisted for at least four million years. William Jungers, Ph.D., of Stony Brook University, and Brian Richmond, Ph.D., of George Washington University, say their finding indicates that the fossil belongs to very early human ancestors.
The research is the first thorough quantitative analysis of the Orrorin tugenensis fossil – a fragmentary piece of femur – which was discovered in Kenya in 2000 by a French research team. Dr. Jungers, Chair of Anatomical Sciences at SBU School of Medicine, and Dr. Richmond, Associate Professor of Anthropology at GWU.
Book creation speaker Larry Dye ”the Creation Guy”, for a creation seminars for your Church or organization.
Book a tour at the Creation Discovery Centre, a creation museum learning centre located in Bow Island, Alberta Canada.
Other recent articles: