Let’s meet a nocturnal monkey from South America!

Did you know?

Different animals are active at different times of day. By active, we mean awake and keeping busy with feeding, traveling, playing, grooming, communicating, or other activities. Biologists find it useful to describe several different activity patterns:

  • A nocturnal animal is mostly active at night.
  • In contrast, a diurnal animal is mostly active during the day.
  • A crepuscular animal is mostly active at dawn and dusk.
  • A cathemeral animal is active during parts of the day or night. In other words, this type of animal might wake up and be active during the day, then have a sleep, then be active again, then rest, then be active in the night, then sleep, and so on!

Have a think!

Why might different animals be active at different times of day? What do you think would happen if all the animals where you live were only active during the day and slept at night?

Can you think of an animal that fits each of the 4 activity patterns (nocturnal, diurnal, crepuscular, cathemeral)?

Can you think of any animals that change their activity pattern in winter or summer?