Poikilotherm

As cold-blooded or poikilothermic ( poikilos ancient Greek ποικίλος " diverse ", " changing "; θερμός thermos " hot " ) refers to animals that do not have a constant body temperature. Generally, but not entirely correct is " cold-blooded " equated with " ektotherm ", as most cold-blooded animals are also ektotherm and vice versa ( " cold-blooded " refers to the fluctuating body temperature of the animals, whereas " ektotherm " describing what makes these fluctuations come about ).

Most animals are cold-blooded, for example, almost all fish, amphibians, reptiles, insects, and other invertebrates. Plants and other organisms are generally cold-blooded (though there are some plants that can control their heat, at least in certain organs ). Relatively equal warm ( homoiotherm ) are against birds and mammals.

The body temperature alternately warm animals nearly equal to the temperature of the environment. They are less active than when hot (compare RGT rule) in the cold. Some cold-blooded animals can in turn influence their behavior body temperature. To find many reptiles specifically for sunny or shady areas. Garter snakes hibernate in dense tangles, so that they can mutually provide warmth itself. States forming insects, such as ants, bees, hornets or termites produce heat by shivering or care in the floor or in the building by ventilation or wing beat for cooling.