Question 1.: Why is Homo Sapiens Sapiens widely distributed around the earth, even in places that are hard to live in, like the Arctic, or hard to get to, like Easter Island.
In http://uniso.karleklund.net/ Part 1 it says: "If the tribe found an ecological niche that allowed it to be successful, it naturally expanded and developed tensions. If it had the opportunity, it fissioned and the two parts moved away from one another to reduce the stress. If it was just a matter of getting too big to exploit the ecological niche properly, we wouldn't have to move that far. But we have to move far enough so we aren't affected by being aware of the people in the other tribe who aren't like us.
When we settle down again, if the place is reasonably fertile our tribe will expand again and fission again, and migrate apart. This repeated fission caused us to spread all over the globe even without the attraction of looking for a better environment. If the environment had been the motivation the whole tribe would move together.
The need to fission to control population is why we are distributed all over the globe in a manner unlike any other primate."
This is not only an unusual phenomenon, because not many other animals are as widely distributed over the earth as Homo Sapiens Sapiens is, but it is a unique phenomenon because the wide distribution is associated with a wide variety of appearance that does not correspond to a variety of species. All the varieties of Homo Sapiens Sapiens are of one species as we occasionally demonstrate by interbreeding of appearance varieties. That is undoubtedly unique.