Principle
Allen's Rule
Endotherms from colder climates tend to have shorter limbs or appendages than the equivalent animals from warmer climates.
Ecological Physiology
Field: Ecological Physiology
Sequence of Expressions
Principle
Bergmann's Rule
Populations and species of larger size are found in colder environments, and species of smaller size are found in warmer regions.
Principle
Gloger's Rule
Darkly pigmented forms of a species tend to be found in more humid environments, e.g. near the equator.