Homo Naledi may be Two Million Years Old (Give or Take)

Francis Thackeray, University of the Witwatersrand

There has been global interest in the announcement of new fossils from a cave called Rising Star in the Cradle of Humankind World Heritage Site in South Africa.

These fossils were recently reported by Lee Berger and his team, who described the discovery of more than 1500 fossils as representing a new species of the genus Homo. It has been called Homo naledi, associated with a name for star in the Sesotho language.

But the age of Homo naledi is not yet known with certainty. The new species has not yet been dated. Unsuccessful attempts had been made by Paul Dirks and members of the Rising Star team to obtain an age. They used techniques applied previously to date a range of fossils. These included Australopithecus africanus, such as the famous “Mrs Ples” skull, as more than two million years old, and fossils of Paranthropus robustus and Homo erectus.

In a new paper in the South African Journal of Science I suggest that Homo naledi lived two million years ago (plus or minus 500,000 years). If shown to be correct, this will help to place Homo naledi in the family tree of human relatives.

The variance is based on the fact that the earliest date for Homo rudolfensis is about 2.5 million years, and the date for certain African Homo erectus samples is about 1.5 million years.

Although different, Homo naledi is most similar to fossils attributed to Homo habilis (about 1.8 million years old), and to a lesser extent to fossils of Homo rudolfensis and Homo erectus.

Taken together I am suggesting that Homo naledi is in the order of two million years old, with upper and lower limits of about 1.5 and 2.5 million years respectively.

Why is dating so important

Estimating —> Read More