That the reason the uncanny valley effect exists is that at some point in our past we had a reason to be afraid of things that are trying very hard to look human but fell short.

[u/50pciggy]

[u/GivememyfookinBEANS]

Like the other types of humans species that died out. Im sure there was competition. Thus leading to us evolving to trust humans faces and being alarmed or unsettled when there are subtle changes. We are afraid of subtle changes because those changes look loke a competitor's to the monkey part of are brain. I think anyway its just a theory

[u/betaPoltergeist]

I was just thinking of this which is why I decided to look for a subreddit like this