thermoregulate

Thermoregulate is a verb meaning to regulate an organism's internal body temperature within a narrow range, despite changes in the external environment. Thermoregulation, the broader noun form, describes the biological processes that achieve this regulation. These processes integrate sensory input, neural control, hormonal signals, and behavioral responses to maintain stable core temperature, which is essential for metabolic function and enzyme activity.

Organisms employ different strategies depending on their thermoregulatory approach. Endotherms, such as mammals and birds, generate heat metabolically and regulate heat loss through vasomotor changes, sweating or panting, and, in some species, non-shivering thermogenesis in brown adipose tissue. Ectotherms, such as many reptiles, amphibians, and fish, rely more on external heat sources and behavioral adjustments, including basking, seeking shade, and changing body orientation.

In humans, the hypothalamus acts as a central thermostat. Responses to cold include shivering, increased metabolic rate, vasoconstriction, and seeking shelter, while heat exposure prompts vasodilation, sweating, and evaporative cooling. Fever is a regulated rise in body temperature during infection, mediated by signaling molecules that raise the hypothalamic set point.

Thermoregulation has implications for health, ecology, and medicine. Abnormal thermoregulation can lead to hypothermia or hyperthermia; fever is a common clinical sign. Understanding thermoregulation informs medical care, climate biology, and industries such as cryopreservation and livestock management.