It’s called “corpse”. Often riddled with diseases.
I remember a documentary about a famous northwest passage expedition that was never seen again. One of the inuit people they talked to during an investigation claimed they found a boat, and in the captain’s quarters they found a body in the bed with a big smile on its face. That would be absolutely terrifying, but apparently that’s what naturally happens to corpses when their lips and gums receed.
Illness, death, and antisocial behavior. All of these were threats we evolved to handle, people who are “a little bit off” in one way or another, who might endanger the group or individual. This, and that our pattern seeking brains don’t like it when something doesn’t easily fit within an existing schema, even more so if it lies just outside of our existing preconceptions.
Obviously, I can’t say that these definitely are the reasons why we experience the uncanny valley, but I think it’s probably a better explanation than… Skin walkers? Or whatever else the meme would be implying.
Still, it’s a cool premise for a horror story at least.
Or it’s just that something feels off, fellow human.
On the other hand, maybe because we’re a highly social species and some people are just crazy, which you see in their face or behavior.
You mostly see this in autistic or ADHD people, even if most of us aren’t dangerous.
Dead bodies probably, as they spread diseases.
But it’s generally pretty obvious when someone’s dead. More likely it has to do with someone alive who may have a communicable disease.
