This theory helps to explain the correlation between body mass and sleep length in mammals as the little brown bat sleeps for 19 hours whereas the elephant sleeps for only 3 hours. Small animals have a high metabolic rate and hence use more energy so therefore need more sleep.
However, the evolutionary approach to functions of sleep can be said to be a reductionist explanation because it fails to address why we have a strong desire for sleep when deprived.
The contrived lab conditions of these studies is unlikely to reflect natural real life circumstances, the animals involved may have altered their own sleeping patterns and behaviour.
This highlights how the Evolutionary Theory of sleep cannot be applied universally to all species, and that the threat of predation may not be the main function of sleep. Horne also proposed that the function of sleep is a combination of both the evolutionary and restorative approach.
On the other hand, herbivores, such as cows, eat food which is low in nutrients i. Predator avoidance is another evolutionary explanation which suggests that if an animal is a predator then it can sleep for longer, whereas prey species cannot afford to sleep long as of predator risk.
We will write a custom essay sample on Discuss evolutionary explanations of sleeo or any similar topic specifically for you Do Not Waste. However there are many exceptions, such as sloths, which are very large yet sleep for 20 hours a day. A2 level EvolutionaryFunction of SleepSleep AO1 — According to the Evolutionary Approach, the function of sleep serves an adaptive purpose and sleeping patterns have evolved naturally in order to promote survival.
Core sleep is mainly SWS and is the vital portion of sleep that an organism requires for brain processes, whereas optional sleep is mainly REM and is dispensable. This shows that NREM sleep is more important for energy conservation; thus supporting evolutionary explanations.
The first element of the evolutionary explanation is that it is necessary for energy conservation. An example of this is unilateral sleep which occurs in dolphins- this is when only a single hemisphere of a brain sleeps at a time.
For example, why do we have a stronger drive for sleep when we are deprived of it?
For example, smaller mammals sleep longer Zepelin and Rechtschaffenwhich fits with the energy conservation theory. Webb proposed the hibernation theory, which proposes that sleep evolved for this exact reason.
Predators, however, such as tigers, can sleep for longer as they are not at threat of this and do not need to adapt to the environment in terms of altering sleeping patterns to aid survival. For example the three-toed sloth has a metabolism so slow that it can die on an full stomach, though it sleeps for 18 hours a day which suggests that there are other extraneous variables which are not taken into account, therefore lessening the internal validity of these studies.
Similarly, migrating birds must remain awake for long periods of time so also use unilateral sleep. Therefore, their unilateral sleeping behaviour has been uniquely adapted in order to increase their chances of survival, supporting the evolutionary theory as a whole.
This supports the view that energy conservation might be the main reason for sleep. Webb suggested that sleep serves the purpose of providing a period of inactivity, therefore conserving energy which would be more efficiently spent at other times e.
For instance, in modern society humans are no longer at risk of predation, unlike animals and our ancestors who would have been under threat during tribal warfare and so needed to sleep less and be vigilant.
Energy conservation Mammals expend a lot of energy just staying awake at a certain body temperature. Discuss evolutionary explanations of sleeo - Paper Example Discuss evolutionary explanations of sleeo Discuss evolutionary explanations of the functions of sleep - Discuss evolutionary explanations of sleeo introduction.
Horne proposed that the restorative approach can explain why we need core sleep, whilst the optional sleep can explain why we might sleep to waste time and conserve energy.
IDA — The Evolutionary Approach can be also criticised as it is reductionist and oversimplifies sleep from the complex process that it actually is. If this did not happen, the dolphin would drown, showing how this evidence supports the idea that sleep is adapted for survival.
On the other hand, examples in the real life world do support the idea that sleep patterns may have evolved in response to certain environmental pressures. They actually found a negative correlation between metabolic rate and sleep, refuting the conservation hypothesis.The first element of the evolutionary explanation is that it is necessary for energy conservation.
Mammals expend a large amount of energy to maintain a constant body temperature, and it is suggested that sleep is a time of enforced inactivity which conserves energy. Evolutionary theory, also known as the adaptive theory of sleep, suggests that periods of activity and inactivity evolved as a means of conserving energy.
According to this theory, all species have adapted to sleep during periods of time when wakefulness would be the most hazardous.
May 15, · The evolutionary explanation of sleep tries to explain why we sleep through the benefits it would bring in terms of survival. Energy conservation Mammals expend a lot of energy just staying awake at a certain body temperature. We have a limited supply of energy so sleep acts as a way of reducing the amount of.
Nov 20, · According to the Evolutionary Approach, the function of sleep serves an adaptive purpose and sleeping patterns have evolved naturally in order to promote survival. One explanation is ‘The Hibernation Theory’ as proposed by Webb (), who suggested that the purpose of sleep is for energy conservation.
The Evolutionary explanations suggest that sleep has evolved into an essential behaviour because it provides some vital biological advantage that promotes survival.
The evolutionary approach has also been called the ecological approach. Discuss evolutionary explanations of the functions of sleep - Discuss evolutionary explanations of sleeo introduction.
Evolutionary explanation of sleep suggests there four mains reasons for it, energy conservation, foraging requirements, predator avoidance and .Download