Changes

==Timing of Activity==

==Timing of Activity==

Cats follow a strict timetable to 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 (Konecny, 1987). This is also implied by the structure and function of the [[cat’s eye]], which has a number of adaptations that improve its function in low light conditions. However, cats have 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 (Randall et al., 1985). 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.

Cats follow a strict timetable to 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<ref>Konecny, M. J.  (1987) Home range and activity patterns of feral house cats in the Galapagos Islands. ''Oikos''. 50, 17-23.</ref>. This is also implied by the structure and function of the [[cat’s eye]], which has a number of adaptations that improve its function in low light conditions. However, cats have 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<ref>Randall, W., Johnson, R.F., Randall, S., Cunningham, J.T. (1985) Circadian rhythms in food intake and activity in domestic cats. ''Behav Neurosci''. 99(6), 1162-1175.
 </ref>. 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==

==Relationship with Human Activity==

The activity of domestic cats is also significantly influenced by human activity. In conditions that more closely resemble a normal domestic environment, cats that were more closely involved with their owners showed greater levels of activity during daylight (Piccione et al., 2012). 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 a large number of generations domestic cats have been exposed to a different set of selection pressures related to photoperiodicity of behaviour and the availability of prey, such that entrainment would have a much lower survival value.

The activity of domestic cats is also significantly influenced by human activity. In conditions that more closely resemble a normal domestic environment, cats that were more closely involved with their owners showed greater levels of activity during daylight<ref>Piccione, G., Marafioti, S., Giannetto, C., Panzera, M., Fazio, F., (2013) Daily rhythm of total activity pattern in domestic
cats (''Felis silvestris catus'') maintained in two different housing conditions. ''Journal of Veterinary Behavior.'' ePub online.</ref>. 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 a large number of generations domestic cats have been exposed to a different set of selection pressures related to photoperiodicity of behaviour and the availability of prey, such that entrainment would have a much lower survival value.

==Key points==

==Key points==