http://news.nationalgeographic.com/news/2013/10/131008-women-handprints-oldest-neolithic-cave-art/Cool article on National Geographic. Someone did a study on handprints in cave paintings and theorized with the data that 75% were women.
Kinda reminds me of the anecdote about the bone with 28 notches:
When I was a student at Cambridge I remember an anthropology professor holding up a picture of a bone with 28 incisions carved in it. “This is often considered to be man’s first attempt at a calendar” she explained. She paused as we dutifully wrote this down. ‘My question to you is this – what man needs to mark 28 days? I would suggest to you that this is woman’s first attempt at a calendar.’
It was a moment that changed my life. In that second I stopped to question almost everything I had been taught about the past. How often had I overlooked women’s contributions?
— Sandi Toksvig.
(this quote probably refers to the Ishango Bone, which has been used to say women were the first mathematicians according to my websearches for this danged quote)