Four separate studies of the skeletal remains of a hominin nicknamed "Little Foot" suggest that it could actually represent an entirely new species of early humans.
According to researchers, some specific features of the skeleton are unique, making it completely different from any other known species.
Little Foot is one of the best-known and most complete fossils in palaeontology, and was unearthed more than 20 years ago in South Africa.
In early 1990s, Professor Ronald Clarke of the University of Witwatersrand was looking through a bone collection when he noticed some foot bones labelled as monkey bones. Clarke studied the bones in details and arrived at the conclusion that they did not belong to an ape.
In 1994, Clarke and his research team arrived at Sterkfontein caves near Johannesburg to excavate the site where those bones were found. It took the research team several years to fully extricate the complete skeleton from the rocks.
"I've spent 20 years getting this skeleton, finding it in the rock in the deep darkness of the cave, locating every bone, and then cleaning it sufficiently so we could identify them in the cave, undercutting them, bringing them out in blocks, cleaning them, reconstructing them," Clarke told New Scientist.
Four separate research teams then examined the fossils in detail, and their findings have now appeared in separate papers, not peer reviewed yet. Researchers conclude that the skeleton represents a new species, which they have named as Australopithecus Prometheus.
Australopithecines were early humans that lived about two to four million years ago. Famous fossil "Lucy" also belongs to this group.
Researchers revealed that Little Foot skeleton dates back approximately 3.67 million years and was from an elderly woman. This woman was just over 130 centimetres tall and was vegetarian. Her legs were longer than her arms, suggesting that she walked using her feet only.
The face of Little Foot was found to be flatter than the faces of members of A. africanus. There are differences in hip bone, skull shape and tooth arrangement also, suggesting that it belongs to a unique species. Researchers think it could be an interim species, which appeared between early Australopithecines and the first Paranthropus - a hominin that co-existed with early Homo species for about a million years.
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