Bergmann's rule

E. Linacre


Carl Bergmann was a 19th century biologist who pointed out that amongst birds and mammals, individuals of the same species tend to be larger and heavier when they lived in colder climates. This applies to pumas (1), bears, koalas, penguins etc. Even in the case of people, there is an obvious difference between the height and weight of a high-latitude Scandinavian and those of an equatorial pygmy. The larger size increases the distance between the environment and the creature’s core, which has to be maintained near 37° C.



(1) Linacre, E.T. & J.E. Hobbs 1977. The Australian Climatic Environment (Jacaranda Wiley), p. 216.