Natural Selection's Influence on Animals Sleep Patterns

“Multiply, vary, let the strongest live and the weakest die” is a quotation from Charles Darwin who claimed the theory ‘Natural Selection’. Another assertion of natural selection from Herbert Spencer is “The survival of the fittest.” These sayings indicate the traits of natural selection, elimination and revolution. Natural selection makes genes, habits, species, and other features that are inferior to the others eliminated.It also executes revolution to adapt the environment. A feature that seems to be useless to refer to but has remained from natural selection is ‘sleeping’. While the animals sleep, they do not search for food, eat, find mates, procreate or feed their young, and the animals are exposed to the danger of being prey. ‘Sleep’ has survived because of its distinctive functions: resting and healing regardless of these some negative aspects of sleep. Although sleep has distinctive functions, natural selectionstill demands revolution on ‘sleep’ to fit into the environment. Each animal’s sleep pattern has been alteredsignificantly by natural selectionon threefactors; the times, the places, the methods.

Firstly, each animal’s sleeping time varies due to its selected life style.Nocturnalanimals sleep in whole daytime and carry out their activities during night to adapt to the climate and to protect themselves from predators.Protection from climate and predators is the main reason of being nocturnal. Nocturnal animal usually lives inan extremely hot place like a desert. Although the average overnight temperature in desert (-3.9°C)is not mild enough for activities, daytime average temperature (38°C) is toohigh that animals cannot move their bodies in the climate. As a result, they choose to sleep in burrows duringthe day. The...

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...al animals’ sleep patterns. The three factors; the time, places and methods are the main alternations of animals’sleep patterns to accommodate themselves to the habitat or to survive. The time is diverse from nocturnal, hibernation to long-short types. The places are also different from water, land to nest. Lastly, various sleeping methods are introduced; unihemishperic, a few different sleeping postures and sleeping in groups. For these reasons, it is definite that influence of natural selection on animals’ sleep pattern is changes. From the changes, animals’ sleep patterns have resulted in diversity. Moreover, since the diversity of sleep patterns is natural selection which is equal to whoever lives in the earth, humans’ sleep pattern is not the only correct one. Therefore, the animals’ various sleep patterns should not be considered as peculiar, but be respected.