Move over Lucy!

It is. There's some disagreement, but some think that this upright primate might have led to both chimps and humans. Kind of turns the usual idea around, that the upright walkers evolved from chimps. So easy to think that evolution always and only advances our way, like adaptation to live in trees is automatically less advanced than to walk upright. It works for us, but another way worked better for the chimps.

Maybe; anthropologists still have a lot of arguing to do.

And who's laughing from the trees watching us use computers, relying on the engineers who built them, and the scientists who developed the theories and those who first made glass and concrete and invented the arch and mitered joints -- etc, etc -- just so some of us could build fancy tree houses?

I love evolution. I was fascinated when I heard about this. The fact Lucy walked upright was groundbreaking. And now here's Ardi, who was walking 1.2 million--MILLION!--years earlier. So cool.