Translated as “through the day” in Greek, this behavioral trait is a non-adherence to a strict diurnal (i.e., active during the day) or nocturnal (i.e., active during the night) activity, often showing several peaks over the diel (i.e., 24 h cycle) day (Tattersall 1987).
Cathemerality is a term applied to the pattern of an organism’s activity that occurs during both the light and dark portions of the 24 h cycle. Thus, a cathemeral organism does not strictly adhere to a diurnal (i.e., active during the day), nocturnal (i.e., active during the night), or crepuscular (i.e., active during twilights) phase, but rather shifts its activity throughout the 24 h. Put more simply, “the activity of an organism can be regarded as cathemeral when it is distributed approximately evenly throughout the 24-h of the daily cycle, or when significant amounts of activity, particularly feeding and/or travelling,...
- Donati, G., & Borgognini-Tarli, S. M. (2006). From darkness to daylight: Cathemeral activity in primates. Journal of Anthropological Sciences, 84, 7–32.Google Scholar
- Donati, G., Santini, L., Razafindramanana, J., Boitani, L., & Borgognini-Tarli, S. M. (2013). Unexpected nocturnal activity in “diurnal” Lemur catta supports cathemerality as one of the key adaptations of the lemurid radiation. American Journal of Physical Anthropology, 150, 99–106.CrossRefGoogle Scholar