Correct option is B
Bergman’s rule states that within a broadly distributed taxonomic clade, populations and species of larger size are generally found in colder environments, while populations and species of smaller size are typically found in warmer regions. This is due to the relationship between body size and thermoregulation, where larger animals have a smaller surface area relative to their body mass, allowing them to conserve heat in colder environments, while smaller animals have a larger surface area to volume ratio, facilitating heat dissipation in warmer environments.
Information Booster:
Bergman’s rule specifically relates to the body size of animals in relation to temperature gradients. It is most applicable to endothermic animals, whose body temperature is regulated internally.
Larger animals are better suited to cold climates because their smaller surface area relative to volume helps minimize heat loss.
Smaller animals are better suited to warm climates because their larger surface area to volume ratio facilitates heat dissipation.
This rule is often observed in various taxa, including mammals and birds.
Additional Information:
(a) Allen’s rule relates to the shape of an organism’s body parts, stating that in colder regions, animals tend to have shorter appendages (ears, tails, limbs) to reduce heat loss, while in warmer regions, animals have longer appendages to increase heat dissipation.
(c) Gause’s rule refers to competitive exclusion, where two species with identical ecological niches cannot coexist in the same environment indefinitely.
(d) Gloger’s rule relates to the color of organisms, stating that darker coloration is found in more humid environments, whereas lighter coloration is found in drier or colder regions.
