Posted: Jul 02, 2022 6:36 am
by Spearthrower
Let me just give a little context - I still haven't worked through all the implications, and honestly, I doubt I have the depth of knowledge ever to be comprehensive. I'll be looking for specialist responses to this, even though there doesn't seem to be a peep at the moment!

So this new dating technique (which may take more technical evaluation regarding its error bars) has produced a date for the sediment in which Australopithecus afarensis fossils were found here, and that date is around 3.5mya.

This is, as far as we believed according to the evidence available, around the same time as australopithecus genus first evolved, with various fossils from other sites now being repositioned as up to a million years after these Sterkfontein individuals. It's also worth mentioning that the Sterkfontein site is actually the most abundant site of australopithecines ever discovered, so a very important site in terms of making statements about available evidence.

The dating we had before for australopithecines would have had them overlapping in time and space with early Homo, plus given the older dating of East African australopithecines, the picture was of S. African australopiths descending from East African groups.

These dates change both of the above. Most significantly, I think, is that if this dating is true, then these individuals were not extant at the time of Homo, and thus there's an extra million years of evolutionary time Plus, the last common ancestor between the various australopithecus species is much older and as yet undiscovered.