What’s different about animals’ sleep?

How animals sleep and how long they sleep varies from species to species. Here are some different sleep characteristics:

1. Birds: Birds often exhibit unilateral sleep, in which one brain hemisphere rests while the other remains awake. This allows them to stay alert so they can take off quickly if necessary.

2. Mammals: Mammalian sleep is usually divided into two types: REM (rapid eye movement) and non-REM sleep. REM sleep is an active stage of sleep in which people often dream, while non-REM sleep is a deeper stage of sleep.

3. Reptiles: Reptile sleep patterns vary from species to species. For example, snakes often choose a warm place to curl up and enter a long sleep state; while turtles float on the water and sleep with only one eye closed.

In summary, while most animals need sleep, how and when each animal sleeps varies, depending on their lifestyle, environment, and physiological characteristics.

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