夜行性 Nocturnal
夜行性形容這些生物會於日間休息，晚間活躍。這習慣可能是一種避敵行為，以避過有較多獵食者活躍的時間，從而減低被捕獵的機會。另外一個原因是要避開日間猛烈的陽光，以減低水份流失。夜行性動物通常擁有發達的聽覺及嗅覺系統，還有特別用以適應晚間活動時的視覺系統。
Nocturnal is used to describe organisms that are active at night and rest during the daytime. This kind of behavior may help them to avoid predators (crypsis). Moreover, this can allow them to avoid intensive sunlight and prevent excessive water loss. Nocturnal creatures generally have highly developed senses of hearing, smell, and specially adapted eyesight.
