Re: Fossil Ancestor of Humans and Primates Is 47 Million Years Old
With fossils you usually do it by sediment layers and yeah I think they can also use carbon dating to make it more exact (they can use half-lives of some other elements and molecules if need be). They can also look at the food they x-rayed in the critters stomach to estimate at what period it existed in. It's not that complex, generally the deeper down in layers the older something will be lol. They're open to some error now and again, but in terms of evolution over millions of years its difficult for them to screw up that badly.
The fossils interesting but the media's emphasis of a possible human link is shit, everyone they've interviewed has said it's unlikely to be that closely related to human ancestry.