Inbreeding Neanderthals Interbred with Denisovans

DNA sequencing of an ancient toe has revealed long-term inbreeding amongst a Siberian-based Neanderthal population.  The sequencing results also reveal Neanderthals, and a sister group, Denisovans, met and reproduced in the Late Pleistocene between 12,000 and 126,000 years ago.