Throughout the animal world, the temperature of the body, or of certain parts of the body, is one of the predominant parameters of their vital balance. Indeed, it is directly related to mobility and influences nutrition, reproduction, and reaction to aggression. Arthropods, in general, are relatively small organisms, resulting in a high surface area-to-volume ratio. The smaller ones heat up faster than the bigger ones but also lose their heat more quickly. The regulation of body temperature is, therefore, very specific and involves, in different proportions, endothermic and exothermic processes (Heinrich 1974).