But the study, published Thursday in the journal Science, shows “that whenever Neanderthals and modern humans have mated, there has been a preference for male Neanderthals and female modern humans, as opposed to the other way around,” said author Alexander Platt, who studies genetics at the University of Pennsylvania.

The 2010 discovery that early humans and Neanderthals once encountered one another and had babies was a scientific bombshell that electrified the field of human origins.