It is generally recommended that people get about eight hours of sleep each night.

Of course, some people thrive on less, and some people need more to feel their best.

Whatever your particular needs, finding the right levels of sleep is important for keeping you alert and healthy.

In the animal kingdom, sleep schedules can be extremely different from creature to creature.

Koala Bears, for example, might sleep more than any other animal out there. These cute animals can sleep between 18 and 22 hours per day according to National Geographic.

This is largely because of what they eat. When possible, koalas will eat almost exclusively eucalyptus leaves. They can eat about 500 grams (17.6 ounces) of them per day, which sounds like a lot.

This type of leaf, however, contains very little nutrients, so they need to consume lots of it in order to get what they need.

To make matters worth for the Koala, eucalyptus is actually toxic and if humans tried to eat this much of it, we would die.

Koalas are able to survive because they have a caecum in their digestive tract, which contains bacteria that can mitigate the toxicity. That added step in the digestive process takes a lot of energy from this animal that is already running on fumes most of the time.

With all this working against them, the Koala preserves energy by sleeping as much as they can.

On the other end of the spectrum is a creature that not only sleeps just 4 hours and 48 minutes per day, but they do it about one minute at a time.

According to a 2009 study, the fire ant species called Solenopsis invicta sleeps about one minute at a time, but takes these ‘power naps’ 253 times per day.

This is one of the quickest sleeping patterns known in nature so far.

The study’s co-author, Deby Cassill, told BBC Earth News:

“The large number and short naps by workers means that jobs in the nest never go unattended. There is always a worker available when the need arises. When work is slow, workers sleep more.”

It should be noted that queens sleep much more, an impressive six minutes at a time with a total daily average of 9 hours of sleep.

Sleep patterns differ  quite a bit between species.

That said, it is necessary for all of us.

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