Kirk had written about that cute polar bear at the zoo, and I thought to add a t…

Kirk had written about that cute polar bear at the zoo, and I thought to add a thought. Polar bears are good at three things: being white, floating well, and surviving cold. All of these are due to an aspect of their fur: it is hollow, unlike the solid strands of other mammals. The fur is actually translucent, and the scattered reflection makes them appear white; the fur’s hollowness also traps air, which both aids the bear in floating and acts as insulation so that they’re like a giant down jacket.

A problem with this is that, in more temperate climates (such as Kumamoto’s), algae often grows within the hair tubes. This does no harm to the bear but makes it turn green, and zoo-goers are oft put off by green polar bears. A solution is to add chemicals to their water, but this would in fact harm the animal. Kumamoto zoo had a problem with this a while back (photo below), but I do not know how they have dealt with it. (I suppose you could shampoo them periodically - volunteers?) - William