In this case, we must believe that genes such as Pax6 first evolved when no vision system existed.Inasmuch as the Pax6 gene family is involved in more than eye development, it is reasonable to hypothesize that some of the other Pax6 functions involving ectodermal tissues (such as nervous system devolopment) were present in ancestral organisms.ReplyDeletePedantMarch 26, 2011 at 6:17 AMI neglected t