Final answer:
Bergmann's rule and Allen's rule explain how organisms adapt to different climates and temperature conditions by either increasing or decreasing their size or altering their body proportions.
Step-by-step explanation:
Bergmann's rule states that within a broadly distributed taxonomic group, populations or species of larger size are found in colder environments, whereas populations or species of smaller size are found in warmer environments. This rule helps explain how organisms adapt to different climates and temperature gradients.
Allen's rule states that animals living in hotter climates generally have longer extremities than closely related animals living in colder climates. This rule helps explain how organisms adapt to different temperature conditions by altering their body proportions.