Whether you measure complexity in biological or cultural building blocks, there can be no doubt that humans are one of the most complex organisms found in the known cosmos. This video charts the course of human evolution, how human primates evolved, how we spread out of Africa and began to populate the planet as well as the tricks and traits we use to ensure our species success.
65 million years ago, a catastrophic even wiped out the the dinosaurs and a small shrew-like creature managed to survive. This became one of the earliest ancestors to humanity from which primates evolved. 2530 million years ago, apes diverged from old world monkeys into their own species demonstrating a higher intelligence. These would eventually diverge and give rise to early examples of the Homo genus, some 2.4 million years ago, and these eventually evolved into modern humans.
From Crash Course: Biology on YouTube presented by Hank Green.