How Long Have We Been Around?

 ...longer than we thought. Better dating has demonstrated that Homo sapiens fossils found in Ethiopia could be 230,000 years old...30,000 years older than previously thought. We know this because we've dated some of the eruptions and the ash layer above them...

And that, of course, is just Homo sapiens. And for so much of that history we were wild animals.

Makes one wonder if the reason we haven't encountered aliens is because none of our neighbors have got past the hunter gatherer stage.

And maybe they're somewhat better off.