Ectothermy

Ectothermy was the physiological ability of some creatures to maintain their body temperatures by absorbing heat from their environment. It was also colloquially referred to as cold-bloodedness, although that term could be misleading—at least one individual interpreted it literally, thinking that an ectothermic creature's blood was frozen solid. The opposite of ectothermy was endothermy. A vast majority of reptiles, such as the Trandoshans or the flying lizards of Da'nor, were cold-blooded organisms, although there were exceptions such as the Ssi-ruuk or the duuvhals. When the weather was too cold for his or her taste, an ectothermic being became torpid and experienced a decrease of his or her intellectual capacities. If no external source of heat was provided in time, that situation could degenerate gradually until death ensued. To,conserve their energy and avoid getting cold during the night, some species like the dewbacks insulated themselves in huddled groups.

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