用英语介绍濒危北极熊原因

The polar bear is the world's largest land carnivore， also known as polar bear， naive. Skin is black， because the hair is usually transparent so that the appearance of white， there are yellow and other colors， great size， ferocity.

Polar bears considerable human vision and hearing， but their sense of smell is very sensitive， is seven times the dog when running the fastest speed of up to 60km / h， 1.5 times the world 100 meters champion. As global temperatures rise， gradually began to melt the Arctic ice floes， polar bears former home has been a certain degree of damage is likely to become extinct in the near future， human needs protection.