jul 11, 1974 - An archaeologist named Donald Johanson finds parts of a skeleton that date back 3.2 million years. The importance of this discovery (other than the skeleton's incredible age) was Lucy's bone structure, which confirmed that Lucy walked upright (affirming that humans had been bipedal before our brains developed).
Added to timeline:
Date:
jul 11, 1974
Now
~ 51 years ago