Another timeline. I'm soon going to string all these together into one big mega-post that will speak to history, pre-history, and evolutionary biology beginning around 63 million years ago. Right now we're looking at the late Bronze Age, the period from 4000 to 2000 BC. I'm going to use "BC" rather than BCE here, for no better reason than that the AP style guide approves of it. On second thought, I won't use BC or BCE here. I'll just assume you, dear reader, know that is what is meant in each of the (always approximate) years provided. So ... here we go. 4000 -- farming settlements first established in the Indus River Valley. Another point around this time: horses have begun to be domesticated on the Eurasian steppes, modern-day Ukraine and west Kazakhstan. 3600 -- in the land between the great rivers Euphrates and Tigris, i.e. Sumer, copper begins to be mixed with tin to create Bronze, giving this era a name. 3500 -- the desertification of much of no...