Stack Exchange Biology is another good Q&A resource that has an answer. https://biology.stackexchange.com/questions/39664/how-could-humans-have-interbred-with-n

Stack Exchange Biology is another good Q&A resource that has an answer. https://biology.stackexchange.com/questions/39664/how-could-humans-have-interbred-with-neanderthals-if-were-a-different-species https://biology.stackexchange.com/questions/39664/how-could-...