Human Evolution :: essays research papers

Evolution is the complexity ofprocesses by which lively organisms establishedon earth and earn been expanded and modifythrough theorized changes in form and function.Human evolution is the biological and culturaldevelopment of the species Homo sapienssapiens, or human beings. Humans evolved fromapes because of their similarities. This can beshown in the evidence that humans had a decreasein the size of the face and teeth that evolved. Earlyhumans are classified in cristal different types offamilies. Creationists believe that humans werealways humans. Humans are classified in themammalian family Primates. In this arrangement,humans, along with our extinct close ancestors,and our nearest living relatives, the African apes,are sometimes placed together in the familyHominidae because of genetic similarities. Two-legwalking seems to be one of the earliest of themajor hominine characteristics to have evolved. Inthe course of human evolution the size of the brainhas been more than tri pled. The increase in brainsize may be related to changes in homininebehavior (See chassis 3). The third major trend inhominine development is the gradual decrease inthe size of the face and teeth. harmonize to theMicrosoft Encarta Encyclopedia 98, the fogeyevidence for direct ancestors of modern humans is split up into the category Australopithecus andHomo, and begins about 5 one thousand thousand years ago (Seefigure 1). Between 7 and 20 million years ago,primitive apelike animals were widely distributedon the African and, later, on the Eurasiancontinents (See figure 2). Although many fossilbones and teeth have been found, the way of lifeof these creatures, and their evolutionaryrelationships to the living apes and humans, remainmatters of active discussion among scientists. Theevidence for human evolution begins with theaustralopithecines. All the australopithecines were bipedal and therefore possible hominines. Indetails of their teeth, jaws, and brain size,however, they modif y enough among themselvesto be divided into five species Australopithecusanamensis, A. afarensis, A. africanus, A. robustus,and A. boisei. Genus Homo are also divided infive different spices Homo erectus, H. habilis, H.sapiens, and H. sapiens sapiens. According toBritannica Encyclopdia, Australopithecusanamensis lived in Kenya between 4.2 million and3.9 million years ago. A. afarensis lived in easternAfrica between 3 and 4 million years ago. Thisaustralopithecine had a brain size a little larger thanchimpanzees. Some had canine teeth more stickingout than those of later hominines. No tools of anykind have been found with A. afarensis fossils.According to Microsoft Encarta Encyclopedia98, between about 2.5 million and 3 million yearsago, A. afarensis clearly evolved into A. africanus.A. africanus had a brain similar to that of itsancestor. However, although the size of the