In a previous article, we have told you about the most sleepy animals in the world. However, there are also 12 animals that don't sleep, or take very few hours of rest daily.
Different factors influence sleep times, but contrary to what was believed some years ago, brain size does not seem to be related to this. Do you want to meet the animals that never sleep? Don't miss the next article on our site!
Are there animals that don't sleep?
Before knowing the species that spend few hours sleeping, it is necessary to ask: "Are there animals that do not sleep?". Formerly, it was believed that the need for more sleep time corresponded to brain mass, that is, the more developed the brain, the more hours of rest the individual needed. However, there are no concrete studies to support this belief. Now, What influences the sleep schedules of animals? Several factors are involved:
- Temperature of the ecosystem inhabited by the species.
- Need to stay alert for predators.
- Possibility of adopting comfortable sleeping positions.
For the above reasons, domestic animals can afford more sleep than wild animals. By not facing the danger of being devoured and living in optimal environmental conditions, the risk involved in surrendering to the unconsciousness of the dream disappears. Despite this, there are wild animals that sleep a lot, like the sloth that, in this case, does so due to the nutritional poverty that its diet provides.
For the scientific community it has been difficult to talk about sleep in animals, since from the beginning they tried to compare their patterns with those of human beings. However, today it has been shown that most species sleep or take some kind of rest, including insects. Doubts persist about more primitive structures, such as marine sponges or plankton. So, are there animals that never sleep? The answer is unknown, mainly because there are still undiscovered animal species today.
With this explanation, it is possible to affirm that, instead of completely insomniac species, there are actually animals that do not sleep much and that In addition, they do it differently from the human being.
Animals that sleep little
In this list of animals that do not sleep, there are some that dedicate very few hours to this activity. These are the animals that sleep less:
1. Giraffe (Giraffa camelopardalis)
The giraffe is one of the animals that sleeps little. He dedicates to this activity only 2 hours a day, but in intervals of just 10 minutes distributed throughout the day. The reason for this? Taking more time to rest would make it an easy target for predators of the African savannah, such as lion and hyena. Also, sleep standing up
two. Horse (Equus caballus)
The horse also sleeps standing up, since when it is free it could be attacked. For this, he takes only 3 hours a day and, in this position, he only reaches NREM sleep, that is, he sleeps without rapid movement of the characteristic eyes of mammals.
In safer environments, the horse can lie down to sleep and only in this position is it able to reach the REM sleep phase, the one during which learning is fixed. For more details, don't miss the following article: "How do horses sleep?".
3. Domestic sheep (Ovis aries)
The sheep is a hoofed mammal that has been domesticated by humans since ancient times. It stands out for its gregarious and diurnal habits. Now, how do sheep sleep and for how long?
Sheep sleep only 4 hours a day and they wake up very easily, because the conditions for sleep must be optimal. They are nervous animals and are in constant threat of being preyed upon, so any strange sound puts the sheep on immediate alert.
4. Donkey (Equus asinus)
The donkey is another animal that sleeps standing up for the same reason as the horse and the giraffe. He spends a maximum of 3 hours a day on this activity. Like the horse, it can lie down to achieve a deeper sleep.
5. Great white shark (Carcharodon carcharias)
The case of the great white shark, and other shark species, is very curious, because sleeps on the move, but not because it be threatened by possible enemies. The shark has gills and it breathes through them. However, its body does not have opercula, bony structures necessary to protect the gills. For this reason, you need to be in constant movement to breathe and cannot stop to rest. Also, its body doesn't have a swim bladder either, so if it were to stop, it would sink.
For these reasons, the great white shark and all shark species are animals that can only sleep on the move. To do this, they access the sea currents, since the flow of water transports them without having to make any effort. For more details, don't miss this article: "How do fish sleep?".
6. Common Dolphin (Delphinus capensis)
The common dolphin and the other species of dolphins have something similar to sharks, which is why they are on the list of animals that do not sleep much. Although they do sleep in intervals of up to 30 minutes, they are forced to do so near the surface. They are marine animals and are part of the mammal family, so they need to breathe out of water to survive. For this reason, the dolphins rest for a maximum of half an hour before coming to the surface for more air. Furthermore, during this resting process, half of their brain remains awake in order not to exceed the resting time and, furthermore, to remain alert to predators.
Don't miss the article "How do dolphins sleep?" to learn more about these wonderful animals.
7. Bowhead whale (Balaena mysticetus)
The bowhead whale, and the other species of the Balaenidae family, are also marine mammals, so they sleep near the surface to get close to the surface for air.
Unlike dolphins, the whale holds up to an hour underwater, this is the maximum time it spends on each lapse of dream As with sharks, you need to be in constant motion to keep from sinking.
8. Pelagic frigatebird (Fregata minor)
The pelagic frigatebird is a bird that nests near the coasts of the oceans. Many people consider that it never sleeps because it is one of the animals that sleep with one eye open. As it does? Find out below!
The pelagic frigatebird spends most of its life in the air, flying from one continent to another. It needs to cover large areas and cannot stop to rest, so it is able to sleep with one section of its brain while the other remains awake. This way keeps flying while resting
Animals that don't sleep at night
Some species prefer to rest during the day and stay awake in the evening. The reason for this? Darkness is the right time to hunt their prey or, on the contrary, in this way they hide from their predators.
These are some of the animals that don't sleep at night:
1. Botfly bat (Craseonycteris thonglongyai)
The botfly bat and other bat species stay awake at night. They are very sensitive to changes in light, so they prefer nightlife.
two. Eagle Owl (Bubo bubo)
The eagle owl is a nocturnal bird of prey that is distributed in Asia, Europe and Africa. Although the owl can also be seen awake during the day, it prefers to sleep during daylight hours and hunt at night.
Thanks to this system, the owl can camouflage itself in the trees until it is close to its prey, which it catches quickly.
3. Aye-aye (Daubentonia madagascariensis)
The aye-aye is a species endemic to Madagascar. Despite its strange appearance, it is part of the primate family. It stands out for its long finger, used to capture the insects that make up its food, and for its large bright eyes.
The aye-aye is nocturnal, which is why it rests during the day.
4. Owl butterfly (Caligo memnon)
The owl butterfly is a species with mostly nocturnal habits. Its wings have a peculiarity: the pattern of spots is similar to the eyes of the owl. Although it is not clear how other animals perceive this pattern, the coloration seems to be due to a way to ward off potential predators. Also, being a nocturnal butterfly, it reduces the number of dangers, since most birds rest during these hours.
