Why do scientists think that Neanderthals and Modern Humans mated with each other rather than just sharing the same DNA through evolution? : AskAnthropology

Wolves did not mate with modern dogs, they evolved into them, and can still produce fertile offspring to this day.

So how do we know that is not the same thing that happened between humans and neanderthals/denisovans?

via Why do scientists think that Neanderthals and Modern Humans mated with each other rather than just sharing the same DNA through evolution? : AskAnthropology.