People killed the Carolina parakeet. An inquiry into their historic population range helps illustrate the challenges of understanding ancient human populations.
Long known as a group of human relatives with big teeth and jaws, these ancient species lived for at least two million years alongside our ancestors.
This year's highlights include ways of finding ancient relatives, how some phenotypes evolved in ancient people, and trace evidence from artifacts.
A comparison of surviving populations of lions in Africa and India with extinct lions, including cave lions from Siberia and Yukon.