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How Man Evolved Essay Research Paper How

How Man Evolved Essay, Research Paper

How Man evolved How did the early man evolve and change into the way we are today?Human Evolution, the natural development of the species Homo Sapiens, or humanbeings. The initial man, called the Hominid was short, not intelligent, and very ape like. The next man lived in the stone age; his name was Homo Habilis. After Homo Habilis,Homo Erectus evolved. He was smarter, more efficient, and walked up-right. And heleaded to us, Homo Sapiens A lot of fossils, bones, and teeth have been found at variousplaces throughout Africa, Europe, and Asia that proved that early man existed. Toolsmade of stone, bone, and wood have also have been discovered and excavated. As a resultof these discoveries, a idea of human evolution during the past 4 to 5 million years hasshown. Most of the ability to make and use tools and other objects comes from the large sizeand complexity of the human brain. through human evolution the size of the brain hastripled. The increase in brain size may be from changes in hominid behavior. Over time,stone tools and other artifacts became more complex and the number of them increased. In addition, the geographic areas occupied by our ancestors expanded during humanevolution. They began to move into the tropical areas of Eurasia sometime after a millionyears ago, and into the tropical parts of these continents about 500,000 years ago. Laterhominids were able to cross the water barrier into Australia. It is likely that the increase inbrain size took place to permit our ancestors to be increasingly able to live in a variety ofenvironments. The third major trend in hominid development is the decrease in the size of the face and page 1teeth. All of the apes are equipped with large teeth that were bigger than humans. Theearliest hominid remains had great teeth that project slightly, but those of all later hominidsshow a great decrease in size. With these changes is a reduction in the size of the face andjaws. As the teeth became smaller and the brain expanded, the face became smaller and itsposition changed. Between 7 and 20 million years ago, early apelike animals were greatly spread out onthe African and, later, on the Eurasian continents. Although many fossils, bones and teethhave been found, the way of life of these mammals, and their evolutionary alikeness to theliving apes and humans are still a question to scientists. None of the fossils apes give signsof being related directly towards us. The fossils for human evolution begins with Australopithecus. Fossils of this primatehave been discovered in a lot of sites in eastern and southern Africa. The genus seems tohave become extinct about 1.5 million years ago and were found 4 million years ago. Allthe australopithecines walked on two legs and gave the appearance of hominids. Theirteeth, jaws, and brain size are different from themselves and force a separation into fourgroups; afarensis, africanus, robustus, and boisei. The earliest australopithecine is afarensis, which lived in eastern Africa between 3 and 4million years ago in Ethiopia and in Tanzania. Afarensis had a brain size a little larger thanchimpanzees. Some of them had dog teeth longer than later hominins. No tools have beenfound with afarensis fossils. Between about 2.5 and 3 million years ago, afarensis evolvedinto a later australopithecine, africanus. Known from sites in southern Africa, africanushad a brain similar to afarensis. As with afarensis, no stone tools have been found withafricanus fossils. Many scientists believe that there was an evolutionary split that led to robustaustralopithecines, africanus evolved into the group Homo. This must have happenedbetween 1.5 and 2 million years ago. Fossils from this time show a mixture of traits. Some Page 2have large brains and teeth. Others have small, Homo-sized teeth and also smallaustralopithecine brains. Skulls and jaws from this period have been placed in the categoryHomo habilis, meaning skillful because of the fossils that were found with stone tools. The earliest evidence of stone tools comes from sites in Africa dated to about 2.5

million years ago. By 1.5 to 2 million years ago, sites in eastern Africa include many stonetools, but also animal bones with scratch marks that experiments show were left by knifemarks. This shows that by this time early hominids were eating meat. Evidence of a large-brained, small-toothed man known as Homo Erectus was found1.5 million years ago. Homo Erectus grew into the tropical areas of the Old World, and atthe end of its evolution, into the warmer parts of Asia. A lot of archaeological sites fromthe time of Homo Erectus show an advancement in toolmaking than was found at theearlier sites. At the cave site of Peking man in north China, there is proof that fire wasused. These studies suggest that hominid behavior was becoming more advanced andefficient. Throughout the time of Homo Erectus the movements in human evolutioncontinued. The brain sizes of early Homo Erectus fossils are larger than those of previoushominids. Later, Homo Erectus skulls were within the size of Homo Sapiens. Between 200,000 and 300,000 years ago, Homo Erectus evolved into Homo Sapiens.Although placed in the same species, these early Homo Sapiens are not the same in lookswith modern humans. New evidence tells that modern man, Homo Sapiens , first appearedmore than 90,000 years ago. There is disagreement with scientists on whether the homininfossils show a relation to the first appearance of Homo sapiens to humans. TheNeandertals (named from the Neander Valley in Germany) occupied some parts of Europeand the middle east from 100,000 years ago until about 35,000 to 40,000 years ago, whenthey disappeared. The arguement over the Neanderthals also asks the question of the origins of humanpopulations, or races. Human populations are shown by a lot of physical differences. Most Page 3of these differences show adaptations to environmental conditions. The Neandertals andother early Homo sapiens are seen as descending from Homo erectus and are ancestors tomodern humans. Other scientists see racial differences n as a recent occurance. The features of theNeandertals are a low, sloping forehead and a large face without a chin. They are tooprimitive for them to be considered the ancestors of modern humans. According to thistheory, the begginings of modern humans can be found in Southern Africa or the MiddleEast. Evolving 90,000 to 200,000 years ago, these humans then spread to all parts of theworld, supplanting the local, earlier Homo sapiens populations. In addition to som fossilfinds from southern Africa, support for this theory comes from comparisons of DNA, aDNA form inherited only from the mother, taken from women distributing ancestors. These studies suggest that humans derived from a single generation in sub-Saharan Africaor southeastern Asia. Because of the tracing through the material line, this work has cometo be called the Eve hypothesis; its results are not accepted by most anthropologists,who consider the human race to be much older. Whatever the outcome of thisdisagreement, the evidence shows that early Homo sapiensgroups were highly efficient at exploiting the sometimes harsh climates of Ice Age Europe. Further, for the first time in human evolution, hominines began to bury their deaddeliberately, the bodies sometimes being accompanied by stone tools, by animal bones, andeven by flowers. Although the features of today’s people did not change human history, some changesdid take place. In addition to the first appearance of the cave art of France and Spain,some anthropologists said that it was during that time when language came about. About10,000 years ago, one of the most important events in human history took place, plantswere farmed, and soon after, animals were used. This made it possible for humans to Page 4civilize. Every thing we know we got from fossils, but we still don’t know enough. The futurefossil discoveries will allow scientists to know what we don’t about human evolution. making advanced and new tools, and increasing our knoledge will help anthropologists find the best locations for fossil hunting more precisely. In the years ahead this will resultin an enormous increase in the understanding of human evolution.