Quote Originally Posted by hospitaller View Post
based on gilmore logic...we all descend from lucy (and we probably do).

...
Yes, if her line did not die out.

As I recall the most recent common female ancestor of all of humanity is estimated to have lived about 80,000 years ago. And the most recent common male ancestor of us all lived about 60,000 years ago. (Or was it 60,000 and 40,000 years?)

I have also read that we are all cousins within approximately the 30th degree. That is, any two individual humans have a common ancestor no more than some 30 generations ago.