The Class of Birds (called Aves) consists of 27 different orders. One of these orders, Strigiformes, contains all the worlds owls, and is divided into two families: Strigidae (the so-called true or typical owls) and Tytonidae (known as barn owls).
Most owls share an innate ability to fly almost silently and also more slowly in comparison to other birds of prey. Most owls live a mainly nocturnal lifestyle and being able to fly without making any noise gives them a strong advantage over their prey that are listening for any sign of noise in the dark night. A silent, slow flight is not as necessary for diurnal and crepuscular owls given that prey can usually see an owl approaching.
Crepuscular, diurnal, and nocturnal are terms which are used to describe the period of the day during which an animal is active.
When an animal is said to be crepuscular, it is active during the twilight hours at dawn and dusk.
Animals who are active during the day are known as diurnal.
Nocturnal animals, on the other hand, only come out at night
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