This is the most thorough documentary on mans impossible journey to conquer and poplulate the planet earth. I've read alot of members refer to this documentary in the past, for those who haven't seen it, prepare to be entertained.

http://www.youtube.com/watch?v=OV6A8oGtPc4

The people that most impressed me in this documentary were the Chuckchi. The way these people have adpated to their enviorment, both physically and mentally is astounding. It's alarming to learn how quickly our bodies can adapt to extreme climates.