human evolution: the last 4 billion years

Here is a timeline of our direct ancestors according to science. Note that some of this is in dispute, but more or less it goes like this (the creatures pictured are reconstructed or are like those in our direct line): 4,000 million years ago: Life begins. 3,900 million years ago: The first cell. 2,500 million years ago: The first … Continue reading human evolution: the last 4 billion years