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![](https://lemmy.world/pictrs/image/eba14d9b-c90b-44ff-aafb-95d5ed4f4eba.jpeg)
There’s a company that makes things like this that have a hard shell covered with felt (I think felt?); cats can be both inside, or on top. I’ll have to see if I can ever find it again; it looked like the cats were quite pleased with that kind of design.
IIRC, it takes around 100 generations to see a significant shift in skin pigmentation due to evolution. For humans, that would work out to about 1700 years for people that were moved from the Nordic regions to sub-Saharan Africa to develop dark skins (assuming that there were no other factors in play).
Evolution can take what seems like a really long time.