In: Anatomy and Physiology
Define Bergmann's rule and Allen's rule in relation to climate adaptation. What is one example of an environmental factor that can lead to development of body-shape characteristics that deviate from those predicted by these two rules?
Bergmann's rule - Thir rule represnts the relation between the external climate (in terms of temperature) and the ratio between body surface to weight in warm blooded animals. According to this, it has been obseved that Animals residing in colder region have the bulkier body than the animals residing in the warmer region. Therfore, this is the adaptive mechanism to save and release of the body heat depending on the climate change.
Allen's rule - This rule represents the body shape of the warm blooded animals in respect to the climate change. According to this rule, body shape of animals in linear in warm climates where as in cold climates ,its got adapted to round or compact in order to prevent the dissipation of heat energy.It is due to the principle that round shape has the smaller surface area to volume ratio.
The example of an environmental factor that can lead to development of body-shape characteristics that deviate from those predicted by these two rules are the nutrient deficiency and stress generated due to chronic disease during the period of growth and development and in menarch of female.