Deagle113
Citizen of Zooville
I think I remember this question! Sorry it got lost I must have missed responding to it. The purpose of fur or any of the other testicular adaptations is to keep sperm at the idea temperature to prevent mutation or damage -- either from excessive heat or cold.I got a question about rabbits (I asked before but I guess it went under in the flood of other questions). I've seen rabbits with both furless as well as furred balls, which is also a factor I try to depict anatomically correct in furry character design. I'm a bit uncertain why both options seem to be a thing. Is it a seasonal thing that they sometimes grow fur and sometimes they do not? Or is it different from breed to breed? A furless scrotum seems to be more normal for rabbits than it is for hares, according to the pictures I saw, but I'm not certain how rare or common it is.
All our domestic rabbit breeds descend from the wild European one, Orcytolagus cuniculus, but the genes for fur distribution have been played with to make all the different varieties. Most of the domestic rabbits I deal with have furless testicles, but I am not surprised about the fur on some breeds--look at Angoras!
One interesting fact about it -- rabbits have open inguinal canals, meaning their testicles can be pulled all the way up into their body vs stopping at a certain point as with many mammals.