Diurnality is an animal behavior characterized by being active during the day and sleeping at night. Animals that are not diurnal might be nocturnal (active at night) or crepuscular (active primarily during twilight ( at dusk and dawn).

Diurnal In animal behavior, diurnality indicates an animal that is active during the daytime and rests during the night. Animals that are not diurnal are either nocturnal (active at night) or crepuscular (active primarily during twilight, i.e., at dusk and dawn). Many animal species are diurnal, including many mammals, insects and birds. The diurnal pattern is often controlled internally by the circadian rhythm (endogenous rhythm) of the animal. In some animals, especially insects, external patterns of the environment control the activity (exogenous rhythms) Answered by: ??? ___________________________________________________________________ Main Entry: nocturnal Part of Speech:adjective Definition: night Synonyms: late, night, night-loving, nightly, nighttime Antonyms: daytime Notes: nocturnal means belonging to or active during the night; diurnal means belonging to or active during the day. I got this from http://www.dictionary.com 's thesaurus! Edited by: QWERTY ___________________________________________________________________