Polar Bears: The Natural History of a Threatened Species

No animal is more symbolic of the Arctic than the polar bear. In the short space of 150,000 years, it has evolved from a grizzly bear into the most specialized predator of the arctic sea ice. Through behavioral, morphological, and physiological changes in a remarkably short period of time, the polar bear has become totally adapted to living comfortably in one of the harshest environments on the planet. Yet, the very survival of this unique mammal is now threatened by global climate warming....