Hi Geoff, None of the three articles cited can definitively rule out the possibility that the genetic remnants of some interbreeding of modern humans with Neanderthals and/or Denisovans. After reading these and a couple of other articles on this topic, it appears that the primary distinction between the Out of Africa hypothesis and the Multi-Regional hypothesis is where this interbreeding took place. The former seems to hold that it took place in Africa and the latter seems to assert that the interbreeding took place outside of Africa. Both hypotheses seem to acknowledge that there was some intermixing of the genes of these different lines. Please notice that #2 below states that there was only "limited interbreeding: one with Neanderthals and one with Denisovans" in the Out of Africa hypotheis. 1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2629215/ 2. http://en.wikipedia.org/wiki/Multiregional_origin_of_modern_humans >http://en.wikipedia.org/wiki/Neanderthal_extinction_hypotheses#Interbreedin g >http://en.wikipedia.org/wiki/Denisova_hominin#Interbreeding_with_modern_hum ans >http://www.ts-si.org/biology/30943-modern-humans-interbred-with-archaic-hom inids-before-leaving-africa =