So... I've seen people suggest long tails for climbing or as hybrid genes. But this is much simpler and just something I think would fit well in Niche.
(Also I want a short tail too, but that has been suggested plenty of times...)
The long tail would give 1 or 2 heat resistance and would be unlocked either automatically or by spending time in hot climate.
(Also if my mane types idea ever gets added in, then this would get a tail tuft with the tuft- and longmane)