"The idea that the Uncanny Valley is because of the ancient hominins we used to interact with during the Pleistocene. Sure, there were interbreeding events, but imagine if you had no idea what a Neanderthal or a Denisovan were and saw one for the first time.
You and your family have been traveling far from home and seek refuge in a cave for the night. You get a fire going, everyone starts to relax. Then out of nowhere, this “almost human” looking being walks up. You all panic and run. Reacting with fear was probably the easiest way to make it out of an encounter like that alive."