Male or female? The first sex determining genes appeared in mammals some 180 million years ago

The Y chromosome, which distinguishes males from females at the genetic level, appeared some 180 million years ago. It originated twice independently in all mammals. The team of Prof. Henrik Kaessmann at the Center for Integrative Genomics and the SIB Swiss Institute of Bioinformatics managed to date these events that are crucial for both mammalian evolution and our lives, because the Y chromosome determines whether we are born as a boy or girl. The results of this research have just been published in Nature.

Fuente : http://www.alphagalileo.org/ViewItem.aspx?ItemId=1...