Science

Next, the researchers investigated whether macaques experience a phenomenon known as the uncanny valley, first identified in humans, in which avatars that are highly realistic but not quite perfect are disliked more than unrealistic ones. They showed macaques variations of the 3D avatar with different levels of realism—sequentially removing the fur, color and texture from the animation—and measured their responses.

They found that monkeys fixated less often on avatars with intermediate levels of realism than on both very unrealistic avatars and the highly realistic 3D animation. This U-shaped relationship between attention and realism is characteristic of the uncanny valley effect.

I thought the uncanny valley was about being considered creeped out, not just dislike. It's also supposed to be subtle but what they removed seems a lot more drastic. It's a cool experiment but idk if it proves much.