Developing the World

A few days ago I was searching Google Images for a map that shows how ancient man colonized the world. Assuming humanity comes from Africa, as modern scientists do, it would seem reasonable they went to Europe relatively quickly. But alas, not so! Due to the changing climate over thousands of years (I'm using generally agreed upon scientific theory, which differs somewhat from my personal beliefs), the spread of homo sapiens went something like this (source):

• Four major groups of humans spread through southern Africa, with the Sahara Desert stopping them from going north.
• One of the four groups went along the eastern coast of Africa through the northern Arabian peninsula to what is now the Middle East.
• Then, said group died due to global cooling.
• A new group of explorers, from the same area as the previous ones, hit the southern coast of the Arabian peninsula and stick to the beaches, passing through southern India and reaching Southeastern Asia, some of the islands, and even China, in the span of 15 thousand years.
• The path these people traveled is then rendered inhospitable as a massive volcanic eruption nearly destroys the human race.
• Some then backtrack to India while others go further up China and into Australia and Oceania.
• The backtracking group goes all the way through the Indian coast and onward through the Middle East to Turkey. They cut directly through Turkey and migrate right through Europe until they almost reach Spain.
• Asian settlers head north into Siberia and Japan, while some Middle Eastern settlers head into northern Africa. 
• Those in the center of Asia go west to central Europe, while some eastern Asians head toward the eastern border of Russia - right next to Alaska. Thousands of years later they cross over to North America and begin exploring it.
• Another Ice Age kills off very northern populations. North American settlers head to the Southern Americas.
• Ice Age thaws, a second round of people show up and head right down.
• People further populate the formerly iced-over North America.
• It's only within the past 10,000 years (mind you I've just covered 160,000 years) that the British Isles, Scandinavia, and northern Russia were populated.

An interesting picture I found. Observe how we were in Australia twenty thousand years before we entered Europe.

Now why are we getting this history lesson? I want to use this as a sort of guide for where I go with the Earth map. I realize that by using Turkey as a starting point, I'm thousands of miles off course already. However it should be possible for me to eventually fix that. Maybe I could pretend there's some kind of ice age going on. With the village Asshur being east of Tubal, I've developed an eastward trend consistent with early man. However I may break that again, as when I finish with Asshur I want to create Cush - that is, Egypt.