According to Allen’s rule, animals in warm climates tend to have:
Allen’s rule predicts that endothermic animals from warm climates tend to have relatively longer or larger appendages, whereas related cold-climate forms tend to have shorter extremities. Ears, tails, limbs, and bills provide surface through which heat can be exchanged. Long appendages increase surface area relative to body volume and, when supplied with warm blood, can dissipate metabolic heat by radiation and convection. Desert jackrabbits’ large vascular ears illustrate this mechanism. In cold environments, compact appendages reduce heat loss and lower the risk of frost injury, as seen in A
Ref: Evolutionary Analysis, Herron & Freeman, 5th Ed., Ch. 10
