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DSST Anthropology as a Discipline

Although the opposable freely moving thumb is present

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Although the opposable (freely moving) thumb is present in most primates, it is particularly developed in man, making him capable of delicate manipulation. A trend in primate evolution has been toward a more elaborate brain. In higher primates, the neocortex functions to receive, analyze, and synthesize information from the senses. The brain of anthropoids is larger, relative to body weight, than that of prosimians and is characterized by a complicated pattern of folds and fissures on the surface. Another evolutionary trend in primates involves the development of offspring both before and after birth. Gestation periods (The period of development in the uterus from conception until birth) are relatively long, allowing for the development of the more complex brain. Ever since recorded history began, and probably before, people have found pieces of rock and other hard material with indentations from the remains of dead organisms. These are called fossils, and the totality of these artifacts and their placement in rock striations is referred to as the fossil record. The fossil record is one of the primary sources of data relevant to the study of evolution. Scientists examine fossils in order to understand the process of evolution and the way specific species have evolved. Dating methods, such as radiometric (but not carbon-14 , which works only for 0-50,000 years before present), show that some of these fossils are tens of millions of years old. Various dating methods have been used and are used today, and while there is some variance in the results from these methods, nearly all of them provide evidence for a very old Earth and for evolution. The geologist sees Relative Time where two or more events are compared without any numerical reference.
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Relative time is where an event is compared in time relative to another event, as opposed to absolute time, where a specific date and time is specified. For example--the Beatles first performed in the United States during the presidency of Lyndon B. Johnson; or January precedes February . Absolute time is measured in some unit (seconds, minutes, hours or years) from some starting point going either forward or backwards. Examples: this is 2003 A.D.; Herodotus studied deltas in Egypt about 420 B.C.; this lecture started l5 minutes ago. The difference between geologic time and the examples given from every day life is the length of time involved. Geologic time is vast, with immense and variable blocks in each relative unit, and very large numbers of years in absolute measurements. Homonoids were ancestors to modern gorillas, chimpanzees, orangutans and humans who diverged 30 million years ago from monkeys. Homonoid characteristics include: large, strong jaw, large brain and partially erect posture. Homonids (human -like primates) diverged from the other homonoids 4-5 million years ago.
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