Which is The Only Animal Known to Hibernate and Dream?

As hibernation is normally associated with animals that enter a period of extremely low activity, a small primate living in Madagascar seems to defy common knowledge.

Fat-tailed dwarf lemurs are the only primates known to hibernate; however, their hibernation is also accompanied by REM-like activity of the brain. REM sleep is widely known to be associated with dreams, hence raising many interesting questions on how the brain functions during a long period of inactivity.

What is the Fat-Tailed Dwarf Lemur?

As it might be expected from the name of the creature, fat-tailed dwarf lemur is a small primate found only in Madagascar. This small animal is unique because of the ability of storing a huge amount of fat in its tail.

Fat becomes a sort of energy reserve for the animal. During the dry season of Madagascar, when finding food can be quite challenging, the lemur enters its hibernation period.

How Does the Lemur Hibernate?

Hibernation is unlike regular sleep in that there are many changes that happen within the physiology of the animal. These include significant drops in body temperature, heart rate, metabolism and activity level.

The fat-tailed dwarf lemur is adapted for such a condition as it gives an opportunity to survive during those times of low availability of food thanks to the fat reserve in its tail.

How does its Brain Function During Such a Special State?

REM-like brain activity found in torpor

During their research on the fat-tailed dwarf lemur, scientists came across the fact that its brain activity during hibernation was not reduced to zero.

What the researchers discovered were short bursts of brain activity during the torpor – the deep inactivity typical for hibernation, some of which looked like REM sleep.

REM, or rapid eye movement sleep, is the stage of sleep connected with dreaming in humans. The similar activity has been discovered in other animals during their sleep. The fact that there is REM-like activity during torpor makes the dwarf lemur rather special.

That is why scientists suppose that the animal may be dreaming while hibernating. What should be pointed out is the fact that brain activity only indicates such an opportunity and not necessarily actual dreams.

What Importance Might This Have?

The link between hibernation and brain function could enable researchers to learn more about how brains adapt to long periods of low metabolism.

Learning from animals that can put their bodies through these extreme states could lead to more knowledge about how brain cells protect themselves during long inactive periods.

Scientists are also curious about how this might one day contribute to studies of brain damage, medical treatment or long trips in space.

Therefore, the fat-tailed dwarf lemur is an important example of a creature that scientists can use to study the connections between sleep, hibernation and brain function.

An Extremely Well Adapted Little Mammal

Even though the fat-tailed dwarf lemur is small, it has a very special way of ensuring its survival. With its capacity to store energy in its tail and go through long periods of hibernation, it can live through times where its surroundings cannot give it any food.

It is also interesting that it is apparently capable of experiencing REM-like brain activity in torpor.