100,000?
Dude, we're talking 12,000-15,000 years ago. The total Human population at that time was no more than a couple of million, and I doubt many of them were hanging out in North Eastern Siberia. These were small nomadic hunter gatherer tribal units which accidently made it across the Bering land bridge into the New World.
One hundred years ago Siberia was a vast empty land with scattered and isolated communities. Imagine what it was like 15,000 years ago when the global population was less than .05% of its current levels and with no transportation technology to speak of, not even domesticated pack animals. Most groups of people were cut off from one another and almost totally alone.