Final answer:
Archaic Homo and Neanderthals differ in physical characteristics and social behaviors. Neanderthals were adapted to colder conditions and had larger brains and different social behaviors compared to modern humans. Interbreeding between Neanderthals and modern humans has been identified through genetic analysis.
Step-by-step explanation:
Archaic Homo and Neanderthals differ in several ways. Archaic Homo is an umbrella category that includes diverse Homo species after H. erectus, while Neanderthals are a specific type of archaic Homo. In terms of physical characteristics, Neanderthals had a larger brain size, thicker skull, and prominent supraorbital ridges compared to anatomically modern humans. They were also adapted to colder conditions and had different social behaviors. Neanderthals and modern humans interbred, and genetic analysis suggests that some modern humans have Neanderthal DNA.