Extreme heat takes a lot of getting used to, just as extreme cold does. No animal is better accustomed to frigid temperatures as the Arctic fox. In addition to its lush fur coat that provides plenty of insulation, its appendages (legs, ears, muzzle) are small in comparison to its central body mass to conserve heat. It even has fur on the bottom of its feet! Like polar bears, its pelt is white to camouflage with the snow.
But what if you have to brave the unforgiving cold without the aid of a thick fur? Once again, we take a look at frogs to see how they deal with their local weather conditions. Rana sylvatica, an Arctic wood frog, quite literally allows itself to freeze over during hibernation. The frog can remain unharmed with up to 65 percent of its body water frozen. All of its bodily functions - breathing, heart rate, metabolism - practically stop, similar to cryogenic freezing processes found in science fiction. Heightened levels of glucose and urea in the body allow R. sylvatica to withstand much lower temperatures without damage to the cells and organs caused by the formation of ice around tissues.
Resilience to toxins.
The kingsnake, called such probably because it'll eat anything it can sink its teeth into (including other snakes), is immune to the venom of prey snakes.
There has been increasing evidence to suggest that doctors who are exposed to radiation in their line of work have developed an enhanced line of defense to protect themselves. While an increase of hydrogen peroxide in the blood is possibly harmful to cells, a correlating increase in a certain antioxidant and enzyme may mean that the body is reacting to protect cells against radiation as well as to systematically kill the cells that are already damaged.
Some of the most interesting adaptations are the ones in which animals change their behaviors in order to adjust to their environments. The diving bell spider lives its entire life underwater, despite breathing air. It weaves a special kind of web that's used as an air bubble, which it takes underneath the water's surface to prey, mate and raise offspring. The spider eventually has to refresh the air supply in the bubble every few days.