Yes, and some animals (mostly birds iirc) do see UV. Boring brown/black birds aren’t so boring in UV. I don’t know the evolutionary pressure necessary for UV, but it could have developed. Red, for instance, is believed to have been useful for us to pick out berries. Wolves, being carnivorous, wouldn’t necessarily need it, so see in yellow blue… or so I read as a theory a while ago.
Yes, and some animals (mostly birds iirc) do see UV. Boring brown/black birds aren’t so boring in UV. I don’t know the evolutionary pressure necessary for UV, but it could have developed. Red, for instance, is believed to have been useful for us to pick out berries. Wolves, being carnivorous, wouldn’t necessarily need it, so see in yellow blue… or so I read as a theory a while ago.