Timing of Feline Activity

Key Points
Cats often adapt their activity patterns to the presence of humans. However, experimentally cats show variation in activity pattern and ability to adapt to light conditions, which may be why some individuals exhibit nocturnal activity which is problematic for owners.

Timing of Activity

Cats follow a strict timetable for movement around their territory in order to avoid contact with each other, taking full advantage of the chemical signals deposited by other cats. Cats are now commonly described as crepuscular (active primarily during twilight - dawn and dusk), and this has been confirmed in radio-telemetry studies. This is also implied by the structure and function of the cats eye, which has a number of adaptations that improve its function in low light conditions. However, cats have also previously been described as nocturnal and diurnal, based on findings from different studies. Under laboratory conditions in isolation from human contact, cats showed random patterns of activity in continuous light, and free-running circadian rhythms in constant darkness. Food intake was stimulated by simulated starlight and the presence of people. There was also a significant level of idiosyncratic variation in entrainment to different light-dark cycles, indicating that some individuals were more capable than others of adapting to different day length.

Relationship with Human Activity

The activity of domestic cats is also significantly influenced by human activity. In conditions that more closely resemble an average domestic environment, cats that were more closely involved with their owners showed greater levels of activity during daylight. Given that man-made lighting, including light pollution, maintains the outdoor environment in towns and cities at a constant level of illumination that resembles the crepuscular period, many cats are exposed to a distorted photoperiod that does not favour proper entrainment and is likely to favour more idiosyncratic patterns of behaviour. For many generations domestic cats have been exposed to a different set of selection pressures related to photoperiodicity of behaviour and the availability of prey. In these altered environmental conditions cats which continued to follow a traditional feline pattern of proper entrainment, i.e. greater levels of activity during the twilight period would have a much lower survival value.