I have heard many times that wolverine (and wolf) are desirable furs for parka ruffs because they easily shed frost that forms from breathing. You’ve seen (and maybe experienced) frost buildup on beards that is difficult and sometimes painful to break off. But by all accounts, frost will fall right off wolverine fur.
My questions is, WHY?
Here are some possible clues.
1) Under the microscope, I don’t readily notice anything special about the scale pattern, medulla, or structure that raises an eyebrow.
2) Some references (non-scientific) mention that the individual hairs have low water content, and this is supposed to be a contributing factor in not forming ice. I am not quite sure how the physics (or the biology) work in that scenario. Is there less free water in the hair and therefore less to bond with the ice on the outside of the hair shaft?
3) Other references mention that the hair has an oil in it that helps. I get it, oil and water don’t mix. But then there is the anecdotal evidence of my dog. He’s a mutt, and in the snow he’s the teflon dog…never gets snowballs matted in his fur, never gets snow stuck in his paw pads. We know plenty of other dogs here who have trouble with snow. And yet, my dog isn’t the kind of dog who has the oily water-dog skin and he doesn’t smell “doggy,” a smell I attribute to those greasier breeds. In fact, he’s asleep next to me as I write this, and smells very nice.
4) The exhibit designer I work with, Paul Gardinier, suggests the effect might be related instead to the geometry of the hair…the fact that it is very long and flexible and there is a whiplash or waving action that causes the hair to flex and the brittle ice to break off before it gets well-established as a thick crust.
5) Finally, I can’t help but wonder, shouldn’t the fur of all the mammals in Alaska resist getting frosted up? Granted, people aren’t breathing on most of those critters, but buildup of frost under high humidity conditions sounds like a biological disadvantage, doesn’t it?
I am pondering this…any ideas? If I get something that rings true, I will post it in the comments…