chronometeran

Chronometeran is a term used to describe a type of animal that possesses a biological clock, allowing it to regulate its internal processes and behaviors according to time. This biological clock is often synchronized with the Earth's rotation, enabling chronometerans to anticipate and respond to changes in light and dark cycles, as well as other environmental cues. The term was coined by biologist John J. McFarland in 1999 to highlight the unique temporal awareness and regulation capabilities of certain organisms.

Chronometerans include a diverse range of species, such as mammals, birds, reptiles, and even some invertebrates. These animals exhibit various temporal behaviors, including circadian rhythms, which are approximately 24-hour cycles that regulate physiological processes like sleep-wake cycles, hormone secretion, and body temperature. Some chronometerans also display ultradian rhythms, which are shorter cycles that occur within the circadian rhythm, and infradian rhythms, which are longer cycles that span multiple days.

The biological clock in chronometerans is typically located in a specialized region of the brain called the suprachiasmatic nucleus (SCN). The SCN receives input from the retina, which detects changes in light intensity, and from other sensory organs, allowing it to synchronize the animal's internal clock with the external environment. This temporal regulation is crucial for the survival and reproductive success of chronometerans, as it enables them to optimize their activities and behaviors in response to changing environmental conditions.

In summary, chronometerans are animals that possess a biological clock, enabling them to regulate their internal processes and behaviors according to time. This temporal awareness and regulation are essential for their survival and reproductive success, and are exhibited by a diverse range of species across the animal kingdom.