What does nocturnal mean?

Nocturnal refers to animals that are primarily active during the night. This behavior is an adaptation that allows various species to hunt, forage, or engage in social activities when it is dark, which can help them avoid predators or take advantage of the cooler temperatures. Many animals have developed specific physiological and behavioral traits to thrive in these night-time conditions, such as enhanced night vision or heightened senses.

The other definitions reflect different activity patterns. Some animals may be diurnal, which means they are active during the daytime. Crepuscular describes animals that are most active during twilight periods, such as dawn and dusk. Lastly, the concept of being active throughout the day and night applies to animals that are not restricted to a particular time of day for their activities, which is not relevant to the term nocturnal. The correct answer accurately captures the essence of how nocturnal animals operate within their ecosystems.