The maybe most relevant ecogeographical rule was formulated by Allen in 1877.
Allen's rule predicts a relationship between climate and morphology as a thermoregulatory adaptation. This ecogeographic principle explains changes in the ratio of body surface area to body mass in hotter versus colder climates. Besides ample empirical cases including cervids, there is also experimental evidence.
Thus, with Allen's rule we would expect short and broad limb proportions for animals in colder climates. Such adaptions were shown experimentally in rats raised at 5 or 28 degrees, and in pig litter mates raised at 5, 20 or 35 degrees.
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