The map has the locations of some modern towns to show the locations.
It shows the southern boundaries of the great ice fields, the glaciers over the mountains, and the great lakes formed by the iced up rivers. And they are into the north, as well as to the east and across the north Pacific into America - and west into Europe.
And with the boats comes more technology - and knowledge to be passed on.
Navigating by the currents, the sea-birds, the winds, the position of the sun, and the stars at night.
Some islands like Flores, as well as the Australian continent are separated by deep sea trenches marking the edges of boundary plates, which even in the most severe ice age remained as open seas and since this was on and near the equator, never froze.
During the ice ages, in this region, the rain forests became less dense, but the living was still easy compared to the northern parts of the world.
New immigrants turned up in the north, thousands of years later when the climate warmed up.
Here is a description of Neanderthal life in what is now the English Midlands, and then possibly as far north as humans in Europe are known to have lived at the time.
They either managed to migrate further south - or they died out.
In south-eastern Britain then linked to what is now Germany by "Doggerland", the ancient Brits either migrated to Spain or the South of France or failed to survive.