Aquatic Ape Theory
There are many debates about how Homo sapiens came to be. Different people have different theories or ideas about the evolution of man. There is the Christian belief that a spiritual power put humans onto the earth, this view is shared by many religions throughout the world, this is not strictly evolution but is called the creationism theory. The theory of evolution was first brought to scientists' attention by Charles Darwin one hundred and forty years ago, where he speculated that man evolved from earlier life form. Since then scientists have been trying to solve the mysteries of mans origins. There is a period of time before approximately five million years ago that has no fossil evidence to prove the step from ape like primates to hominids, the theories of evolution all ponder on this period to try and find "the missing link". There are many theories of human evolution, although just two are widely debated by scientists today. The savannah hypothesis is a theory that man evolved from the primates that were forced down from the trees in the African rainforests to the dry African savannah and thereby had to adapt to this new way of life. The other is the aquatic ape theory. This theory says that man evo
As the body lost its hair it had to adapt to keep warm, the aquatic ape theory believes that the adoption of a subcutaneous fat layer was this adaptation. Humans are the fattest primates, they have ten times as many fat cells as would be expected in an animal of the same size. There are only two types of animals that have this fat layer, hibernating animals and aquatic animals. The hibernating animals only have fat seasonally, whereas humans and aquatic animals have this fat all year round. Humans have different sweat glands to most mammals, these glands lose large amounts of water and salt. If humans were evolved on the savannah with these sweat glands they would have dehydrated very quickly, as water and salt are needed within the body in hot conditions. Another way that humans lose salt and water is through the tear ducts. Humans cry tears of emotion and tears in response to a stimulus such as smoke or dust, no other land mammal does this. There are however marine mammals that can do this such as a walrus, they can weep due to excitement when feeding or weep when they have induced too much water and the body tries to expel some of it. The aquatic ape theory argues that in order for the aquatic apes to lose the excess salt ingested in the salty environment these adaptations were necessary. The human body has another type of gland that secretes oil known as sebum. Other primates such as chimpanzees have these glands although theirs are very small whereas the human glands are enormous. The aquatic ape theory leaflet states that "the only known function of sebum is that of waterproofing the skin or fur". The human brain has increase in size throughout evolution, from the relatively small brain of the australopithecus to the large brain of the Homo sapiens. In the aquatic ape theory the brain's jump in size from the primate to the Homo sapien is put down to two theories. The type of food in the aquatic environment contained two nutrients essential for growth of the brain. These nutrients are omega-3 fatty acids which build brain matter and DHA which is a chemical that helps stabilise normal brain functioning (Verhaegen, 1985). The other theory is that the change of diet caused an increase in brain size. As the human like primate changed its diet from a mainly herbivorous one to an omnivorous/carnivorous one. This increased meat diet decreased the size of the digestive tract as plant matter takes longer to digest than meat, thus meaning the body had extra energy to use on another system. The body used this increased store of energy to increase the size of the brain and make it more specialised. Savannah theorists believe that when the apes lost their fur they needed protection from the cold nights and this fat layer provided the insulation. If humans had this fat layer on the savannah they would be slow and unfit, which would make them vulnerable to predators. Human babies when born are very chubby and fat compared to the other primate babies, if the other primate babies were born like this they would be unable to hold on to their mothers when fleeing danger, or in the tree tops and could die by falling. Human babies accumulate fat before and after birth, some of this being white fat, which is extremely rare in newborn mammals. This fat layer is attached or bonded to the skin. In most other land mammals the fat is deposited around the internal organs and muscles. White fat is not good for respiration, that is, it does not readily break down to produce energy and heat. Although it is good for insulation in water and makes babies have a certain amount of buoyancy. The result of a vertical spine meant that human sex organs were frontal meaning humans have frontal sex, the only other mammals that have frontal sex is sea mammals such as the dolphins and whales. Aquatic ape theorists argue that if humans did evolve from the apes on the savannah why don't they have mounted sex. The only other primate known to have frontal sex
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Elaine Morgan, Phil Nicholls, Europe Homo, Charles Darwin, Ape Theory, aquatic ape, Alistair Hardy, ape theory, aquatic ape theory, Max Westerhofer's, Danakil Island, ape hypothesis, aquatic ape hypothesis, homo sapiens, fat layer, aquatic ape theorists, ape theorists, human primates, sweat glands, animals fat, fur protect, theory aquatic ape, ape theory theory,
Approximate Word count = 2828
Approximate Pages = 11 (250 words per page double spaced)
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