The discovery of the Homo naledi fossils in the Rising Star cave in South Africa has stirred up global interest among scientists. One of the aspects of the Homo naledi that scientists have yet to uncover is the age of this new ancient human species.
Now, a new report by Francis Thackeray, a paleoanthropologist at the University of the Witwatersrand, suggested that the new human species Homo naledi may have roamed around the Earth about two million years ago.
Previous attempts to obtain the age of the Homo naledi were unsuccessful, Thackeray said. To find the age of the Homo naledi, Paul Dirks, as well as some members of the Rising Star team led by Lee Berger, used methods that were applied to date a range of fossils. These included the fossils of Mrs. Ples, an Australopithecus africanus; fossils of Homo erectus; and fossils of the Paranthropus robustus.
In a report featured in the South African Journal of Science, Thackeray explained that he developed a mathematical technique to measure the size of the skull of Homo naledi. He compared his measurements to the size of the skulls of other pre-historic human species. The fossils of Homo naledi are similar to Homo habilis fossils, which are dated to be 1.8 million years old.
Thackeray said the age of the Homo naledi may be 500,000 years less or more.
He explained that the variance in the age of the Homo naledi is based on the fact that the date for samples of the Homo rudolfensis is 2.5 million years, while the date for samples of African Homo erectus is 1.5 million years. The Homo naledi may have been an early ancestor of the Homo erectus.
"If shown to be correct, this will help to place Homo naledi in the family tree of human relatives," said Thackeray.
The Rising Star team that discovered the Homo naledi found more than 1,500 fossils that represented the new ancient human species. The word naledi is a name for star in the Sesotho language. Regarding the Homo naledi's features, scientists said it had a small brain with a volume of 500 cubic centimeters, making it similar to Australopithecus.
Meanwhile, Thackeray said his report has already attracted interest from universities in Europe and the United States. The report's findings illustrate the potential to advance scientific knowledge, he added.