Here is a video of Zoo monkeys in Japan forming a "monkey ball" to stave off the winter cold. Monkey balls can include as many as 100 monkeys with
the alpha male getting the most warmth in the middle.
It's nice to be in the middle............ then the gas is passed
That is the best why to keep from getting to cold. My girlfriend loves cold nights do to the heat I put off when I sleep. I just wish she did the same