AGE OF CONTROVERSIAL HOMO ERECTUS SKULL CONFIRMED AT 1.9M YEARS
A new study verifies the age and origin of one of the oldest specimens of Homo erectus -- a very successful early human who roamed the world for nearly 2 million years. In doing so, the researchers also found two new specimens at the site -- likely the earliest pieces of the Homo erectus skeleton yet discovered, Science Daily reported, the same day the study was published by the journal Nature Communications.
"Homo erectus is the first hominin that we know about that has a body plan more like our own and seemed to be on its way to being more human-like," said Ashley Hammond, an assistant curator in the American Museum of Natural History's Division of Anthropology and the lead author of the new study. "It had longer lower limbs than upper limbs, a torso shaped more like ours, a larger cranial capacity than earlier hominins, and is associated with a tool industry -- it's a faster, smarter hominin than Australopithecus and earliest Homo."
In 1974, scientists at the East Turkana site in Kenya found one of the oldest pieces of evidence for H. erectus: a small skull fragment that dates to 1.9 million years.
The East Turkana specimen is only surpassed in age by a 2-million-year-old skull specimen in South Africa.
But there was pushback within the field, with some researchers arguing that the East Turkana specimen could have come from a younger fossil deposit and was possibly moved by water or wind to the spot where it was found.
To pinpoint the locality, the researchers relied on archival materials and geological surveys.
"It was 100 percent detective work," said Dan Palcu, a geoscientist at the University of São Paulo and Utrecht University who coordinated the geological work. "Imagine the reinvestigation of a 'cold case' in a detective movie. We had to go through hundreds of pages from old reports and published research, reassessing the initial evidence and searching for new clues. We also had to use satellite data and aerial imagery to find out where the fossils were discovered, recreate the 'scene,' and place it in a larger context to find the right clues for determining the age of the fossils."
Although located in a different East Turkana collection area than initially reported, the skull specimen was found in a location that had no evidence of a younger fossil outcrop that may have washed there.
This supports the original age given to the fossil. Within 50 meters of this reconstructed location, the researchers found two new hominin specimens: a partial pelvis and a foot bone.
Although the researchers say they could be from the same individual, there's no way to prove that after the fossils have been separated for so long. But they might be the earliest postcrania -- "below the head" -- specimens yet discovered for H. erectus.