Cool Facts About Cold & Warm Blooded Animals

Habitat

• Warm-blooded animals can live in almost any environment on the Earth's surface. This is because they are able to keep the inside of their bodies at a relatively constant temperature by generating their own heat, or losing it, as required. By contrast, the bodies of cold-blooded creatures become the same temperature as their surroundings. The muscle activity of cold-blooded animals is dependant on chemical reactions that are quicker when it is warmer. This is the reason that animals such as reptiles lie in the sun. According to NASA, cold-blooded animals maximize the amount of sunlight reaching their skin by lying with their bodies perpendicular to the direction of the sun. They can also darken the color of the skin to better absorb heat, and increase their surface area by expanding their rib cages.

Energy

• Cold-blooded animals require much less energy to survive than warm-blooded animals. According to Glogster EDU, warm-blooded animals need between five and 10 times more food than their cold-blooded counterparts. This is because the heat loss from a warm-blooded animal's body is proportional to its surface area, while the heat generated is proportional to the animal's mass. The ratio of an animal's body's surface to its mass decreases as the animal gets larger. Therefore, the larger an animal is, the more heat it can generate relative to the amount of heat it loses.

Disease

• A reptile's immune system is more efficient when the animal is warmer. Despite this, says Glogster EDU, cold-blooded animals sometimes lower their body temperature when they have an infection. This is to stem the growth of bacteria that grow more slowly in colder temperatures. Warm-blooded animals are disadvantaged when it comes to contracting illnesses because their relative warmth provides the perfect environment for bacteria, viruses and parasites to live in.

Excpetions

• Some animals defy the easy categorization of being either warm-blooded or cold-blooded. Examples include echidnas, also known as spiny anteaters. These animals maintain their body temperature between 77 and 98.6 degrees Fahrenheit, but have difficulty cooling down if it goes beyond that. Both mole rats and bats cannot maintain a constant body temperature. Bats' temperatures drop when they are not active. Mole rats live underground so that their surrounding temperature, and therefore their own, is relatively stable.