Since 2010, scientists have known that Neanderthals and our ancestors had offspring together, and those hybrid babies passed down their genes to many present-day people. But the idea of “archaic introgression,

Most people alive today carry fragments of Neanderthal DNA in their genome.

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...