"Some animals do not fall neatly into the categories of being warm or cold-blooded . Bats , for example , are mammals who can not maintain a constant body temperature and cool off when they are not active . Echidnas maintain a range of body temperatures which usually lies between 77 and 98.6 degrees Fahrenheit and have difficulty cooling down . Mole Rats are another group of mammals who are unable to regulate their body temperature , however , since they live underground , the temperature of their environment does not change much . Some warm-blooded animals , such as bears , groundhogs , gophers and bats hibernate during the cold winter . During hibernation these animals live off of stored body fat and can drop their body temperatures by as much as 50 degrees Fahrenheit . The Hawk Moth is an insect which can raise its body temperature well above the temperature of its surroundings when it is flying because of its huge wing muscles which generate heat when in use . Bees are another example of insects that can raise their body temperatures above that of their environment by moving their wings rapidly to generate heat ."
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"Bats , for example , are mammals who can not maintain a constant body temperature"
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