My theory is very simple: All Neanderthal males were killed and the females mated with. Over a period of thousands of years that is. Neanderthals lived in small groups of around 30. There were around 30,000 Neanderthals in total during the time Homo sapiens began to enter Europe. That would mean that there were around 1,000 Neanderthal groups spread all over Europe and some Asia. Homo sapiens likely entered the regions in large groups of males. Groups of 30 Neanderthals had maybe 5-8 adult males of “fighting age” meaning not children and not seniors. They were easily outnumbered and probably surprised by the invasions. They didn’t prepare for what they didn’t see coming. Similar to the Basques who later would … Continue reading “Why is there no Neanderthal y-DNA in modern humans?”