[The Scientist (OP)]

How did people moving to tropical and polar regions adapt to the temperature?

Please elaborate upon explanation. Thanks!

[evan_au]

It is thought that humans originated in Africa - some recent fossil finds in Morocco suggests that some hominids were living in tropical climates for a long time.

The relative hairlessness of humans allows for more effective sweating, which allows us to be more active on hot days. But it also makes sense to rest under a tree or in a cave or in a constructed shelter in the hottest part of the tropical day.

In moving out of Africa, humans were exposed to some very cold climates. Use of fire and clothes certainly would have helped here, as well as sheltering in caves. The light-colored skin of northern Europeans seems to be an adaptation to reduced sunlight intensity, and helps prevent vitamin D deficiency.

The development of agriculture allowed long-term storage of seeds for the winter, which certainly helps survival in rugged environments.

[chris]

This interview with Nina Jablonski on evolution of human skin colour and hair characteristics is quite relevant to this discussion.

[alancalverd]

Having developed weapons and collaborative hunting, and worked out how to control fire, it was fairly easy to adapt to different prey and terrain. Modern native Americans (particularly Inuit)  and Saami wear clothing and occasionally adopt a lifestyle that would have been entirely normal in the Neolithic period. Though steel knives, composite bows and rifles have made some tasks a lot easier, foraging, fishing, food preservation, clothes, skis and even canoe construction haven't changed much. The use of dogs for hunting, herding and transport probably goes back 20,000 years or so .   

[chris]

The use of dogs for hunting, herding and transport probably goes back 20,000 years or so .

The first people to arrive in Australia 40-50,000 years ago must also have had boats, because despite sea level fall owing to the ice-age, the Torres strait dividing Northern Australia from Indonesia was still very deep and very much inevidence. Extraordinary, when you think about it, given how long ago that was...