I saw this in 1982 at the cinema, aged sixteen, and loved it. I've never watched it again, until today. Obviously science, knowledge and discoveries have moved on in the past 40 years. It's still a great film. There's an awful lot wrong with it; early modern humans were essentially like us not like apes, so the ape-like behaviour they display is jarring and unconvincing. In addition, the hairy gorilla-like creatures who attack them at the beginning; who are they supposed to be? But it's a pretty good stab at showing how our early ancestors lived.