Fossils from the rich hominin deposit at Sterkfontein in South Africa are now argued to by some to be considerably older than originally thought and are contemporary with Australopithecus afarensis in East Africa.
The study further highlights the importance of detailed stratigraphic analysis in assessments of accurate dating cave sites in South Africa and the limitations of the previously relied upon faunal age estimates.
previous ages from the A. africanus fossils recovered from Member 4 at the Sterkfontein cave site dated to approximately 2.1 to 2.6 million years however, this recent study has suggests the ages of the follis to be much older, approximately 3.41 million years.
Granger et al, argues that the previously dated flowstones are stratigraphically intrusive and therefore underestimate the true age of the fossils. The new dates demonstrate the limitations of the widely accepted concept that A. africanus descended from A. afarensis and suggests a more complex family tree in the human evolutionary process.
Read the full research article published in Earth, Atmospheric and Planetary Sciences Anthropology here.