[pierrem15]

Accident plays a big role: in all likelihood, the combination of the quick drop in temperature from the Younger Dryas destroying habitat and human pressure reduced them to an isolated population in Novaya Zemlya where genetic isolation finished them off about 3,000 years ago.

Just like the dinosaurs, an abrupt combination of accidents finished them off. We anthropomorphize nature when we ascribe purposes: "all there is is matter in motion." Unless you are a believer, in which case God may have a purpose, but that is probably unknown to us.

[PIF]

the combination of the quick drop in temperature from the Younger Dryas

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They were gone with the Event that caused the Younger Dryas. Humans had nothing to do with the mass extinctions.