Kate Underwood answers the question Are Felines Nocturnal?:
It’s a common response for cat owners to believe their cats are nocturnal, and that’s why they keep odd hours. However, nocturnal is not the correct term for domestic cats. There are three terms for the time of day when an animal is the most active: nocturnal, diurnal, and crepuscular.
No, cats are not nocturnal, although that’s a popular misconception. As AllThingsNature.org explains, cats are crepuscular, not nocturnal.
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Cats are crepuscular animals, meaning they are naturally wired to be at their most active during twilight. So during those hours just before you’d go to bed and the early morning or dawn hours, your cat may be inclined to meow, nudge, or otherwise try to engage with you.
As AllThingsNature.org notes, “crepuscular” originates from the Latin word “twilight.” Crepuscular animals can take advantage of those low-light hours between day and night for hunting and finding water. Being crepuscular benefits some animals because visibility becomes more challenging to predators in the wild, and the temperatures are cooler.