Either that, or “you have two different groups of hominins with two totally different toolmaking traditions occupying the same landscape at the same time yet never intermixing,” said the study’s lead author, Daniel Adler, an anthropologist at the University of Connecticut.2014 September 29, Douglas Quenqua, “Toolmaking May Have Risen Independently”, in The New York Times:
This idealized structure may not exist in reality, considering the high divorce rate and the intermixes of maternal-paternal dominance characteristics.1973, Wilson Brian Key, Subliminal Seduction, →ISBN, page 83: