They find in the arctic frozen remains of a primate that seems to be roughly as ancient as some of the australopithecus, so they call it (if I remember correctly) "borealopithecus" but I googled this word and got nothing.
Anyway they manage to clone (I think) a living organism from these remains and he (he is a male) is left to survive in an arctic environment, with a herd of reindeers that he manages to semi-domesticate. He manages not just to survive, but make elaborate clothes, tools, various artifacts including a sleigh
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