23. Everybody Sleeps

Every animal in the world sleeps to rest and heal from the dayŐs stresses.  Some animals sleep in the night and are active during the day, which we call diurnal.  Other animals sleep during the day and are active at night, which we call nocturnal.  The type of animal that we are most familiar with and that has the most known sleep pattern is mammals.  Mammals are animals that have hair, make milk, and donŐt lay eggs.  Giraffes sleep for the shortest time of any large mammal, sleeping only 1 to 2 hours a day.  The small brown bat holds the title for the longest sleeping animal, sleeping up to 22 hours a day.  Humans sleep about 8 hours a day, which is pretty long for the larger mammals. We have to sleep so much because of our more advanced brains which need extra time to process what happened when we were awake.

      Other types of animals like fishes, reptiles, birds and insects have different sleep patterns from us mammals.  Sleep in fish is not very well studied.  We think that fish that have to move to breathe donŐt sleep at all.  Some bigger fish sleep 8 hours like we do.  Reptiles sleep for around the same time as mammals but they donŐt have one stage of sleep that we do.  BirdsŐ sleep is almost exactly like mammals with the only difference being for migratory birds.  Wild migrating birds need only a few minutes of sleep a day during migration.  Insects have the most odd sleep patterns as compared to us humans.  Some ants sleep only a minute at a time but sleep around 250 times a day.  Other insects sleep longer times, around 10 to 15 minutes, but only a few times a day.  Sleep helps the world go round.

Everybody Sleeps


1.   Why do animals sleep?

(to rest and heal from the dayŐs stresses)


2.   What are night active animals called?



3.   What are some things that let us know that an animal is a mammal?

(fur, does not lay eggs and gives milk)


4.   What mammal sleeps the shortest amount of time?



5.   How long does the brown bat sleep?

(22 hours)


6.   Why do humans have to sleep so long?

(to process activity from a large brain)


7.   When do some wild birds sleep a few minutes each day?

(when migrating)


8.   Who never sleeps because they have to move to breathe?

(some fish)


9.   How do some ants sleep?

(one minute at a time up to 250 times a day)


1.         Tell some facts that will explain how you sleep.