Imagine yourself, being one of those hardy souls that accepts the challenge of a “polar bear plunge” festivity, by throwing their warm body into frigid ocean water. That is a challenge to any warm, mammalian body and just as all mammals, marine mammals need to maintain a body temperature of 98.6℉ (37℃). To be able to do that, they have evolved several anatomical and behavioral adaptations to neither overheat nor get too cold. For example, they use blubber and/or fur as insu

The smallest toothed whale, the Vaquita porpoise, is still a hefty size compared to the smallest primate, the pygmy marmoset, which is a comfortable handful. Why is that? This has to do with all mammals trying to maintain a body temperature of 98.6℉ (37℃), by having all cells in their bodies produce heat. Since water conducts heat much better than air, mammals living in water face much higher heat loss to the environment than land mammals. Everything else being equal, a large