Neandertals And Other Early H Sapiens example essay topic

... aw muscles. The robust became extinct about 1.5 million years ago. The Genus Homo Although scientists do not agree, many believe that after the evolutionary split that led to the robust, A. africanus evolved into the genus Homo. If so, this evolutionary transition occurred between 1.5 and 2 million years ago. Fossils dating from this period display a curious mixture of traits. Some possess relatively large brains-several almost 800 cc (about 49 cu in) -and large, -sized teeth.

Others have small, Homo-sized teeth but also small, -sized brains. A number of fossil skulls and jaws from this period, found in Tanzania and Kenya in eastern Africa, have been placed in the category H., meaning "handy man", because some of the fossils were found associated with stone tools. H. many traits that link it both with the earlier and with later members of the genus Homo. It seems likely that this species represents the evolutionary transition between the and. The earliest evidence of stone tools comes from sites in Africa dated to about 2.5 million years ago. These tools have not been found in association with a particular homini ne species. By 1.5 to 2 million years ago, sites in various parts of eastern Africa include not only many stone tools, but also animal bones with scratch marks that experiments have shown could only be left by human like cutting actions.

These remains constitute evidence that by this time early homini nes were eating meat, but whether this food was obtained by hunting or by scavenging is not known. Also unknown at present is how much of their diet came from gathered vegetable foods and insects (dietary items that do not preserve well), and how much came from animal tissue. It is also not known whether these sites represent activities by members of the line leading to Homo, or if the robust were also making tools and eating meat. Fossil evidence of a large-brained, small-toothed form, known earliest from north Kenya and dating from 1.5 to 1.6 million years ago, has been placed in the species H. erectus. The first part of the time span of H. erectus, like that of the earlier-in-time homini nes, is limited to southern and eastern Africa. Later-between 700,000 and a million years ago-H. erectus expands into the tropical areas of the Old World, and finally at the close of its evolution, into the temperate parts of Asia.

A number of archaeological sites dating from the time of H. erectus reveal a greater sophistication in toolmaking than was found at the earlier sites. At the cave site of Peking man in north China, there is evidence that fire was used; the animal fossils that have been found are sometimes of large mammals such as elephants. These data suggest that was becoming more complex and efficient. Throughout the time of H. erectus the major trends in human evolution continued.

The brain sizes of early. erectus fossils are not much larger than those of previous homini nes, ranging from 750 to 800 cc (45.8 to 48.8 cu in). Later H. erectus skulls possess brain sizes in the range of 1100 to 1300 cc (67.1 to 79.3 cu in), within the size variation of Homo sapiens. Early Homo sapiens Between 200,000 and 300,000 years ago, H. erectus evolved into H. sapiens. Because of the gradual nature of human evolution at this time, it is difficult to identify precisely when this evolutionary transition occurred, and certain fossils from this period are classified as late H. erectus by some scientists and as early H. sapiens by others.

Although placed in the same genus and species, these early H. sapiens are not identical in appearance with modern humans. New fossil evidence suggests that modern man, H. sapiens sapiens, first appeared more than 90,000 years ago. There is some disagreement among scientists on whether the homini ne fossil record shows a continuous evolutionary development from the first appearance of H. sapiens to modern humans. This disagreement has especially focused on the place of Neandertals (or Neandertals), often classified as H. sapiens neanderthal is, in the chain of human evolution.

The Neandertals (named for the Ne ander Valley in Germany, where one of the earliest skulls was found) occupied parts of Europe and the Middle East from 100,000 years ago until about 35,000 to 40,000 years ago, when they disappeared from the fossil record. Fossils of additional varieties of early H. sapiens have been discovered in other parts of the Old World. The dispute over the Neandertals also involves the question of the evolutionary origins of modern human populations, or races. Although a precise definition of the term race is not possible (because modern humans show continuous variation from one geographic area to another), widely separate human populations are marked by a number of physical differences.

The majority of these differences represent adaptations to local environmental conditions, a process that some scientists believe began with the spread of H. erectus to all parts of the Old World sometime after a million years ago. In their view, human development since H. erectus has been one continuous, in-position evolution; that is, local populations have remained, changing in appearance over time. The Neandertals and other early H. sapiens are seen as descending from H. erectus and are ancestral to modern humans. Other scientists view racial differentiation as a relatively recent phenomenon. In their opinion, the features of the Neandertals-a low, sloping forehead, large brow ridge, and a large face without a chin-are too primitive for them to be considered the ancestors of modern humans.

They place the Neandertals on a side branch of the human evolutionary tree that became extinct. According to this theory, the origins of modern humans can be found in southern Africa or the Middle East. Evolving perhaps 90,000 to 200,000 years ago, these humans then spread to all parts of the world, supplanting the local, earlier H. sapiens populations. In addition to some fragmentary fossil finds from southern Africa, support for this theory comes from comparisons of mitochondrial DNA, a DNA form inherited only from the mother, taken from women representing a worldwide distribution of ancestors.

These studies suggest that humans derived from a single generation in sub-Saharan Africa or southeastern Asia. Because of the tracing through the material line, this work has come to be called the "Eve" hypothesis; its results are not accepted by most anthropologists, who consider the human race to be much older. See also RACES, CLASSIFICATION OF. Whatever the outcome of this scientific disagreement, the evidence shows that early H. sapiens groups were highly efficient at exploiting the sometimes harsh climates of Ice Age Europe. Further, for the first time inhuman evolution, homini nes began to bury their dead deliberately, the bodies sometimes being accompanied by stone tools, by animal bones, and even by flowers. Modern Humans Although the evolutionary appearance of biologically modern peoples did not dramatically change the basic pattern of adaptation that had characterized the earlier stages of human history, some innovations did take place.

In addition to the first appearance of the great cave art of France and Spain See CAVE DWELLERS, some anthropologists have argued that it was during this time that human language originated, a development that would have had profound implications for all aspects of human activity. About 10,000 years ago, one of the most important events in human history took place-plants were domesticated, and soon after, animals as well. This agricultural revolution set the stage for the events in human history that eventually led to civilization. Modern understanding of human evolution rests on known fossils, but the picture is far from complete.

Only future fossil discoveries will enable scientists to fill many of the blanks in the present picture of human evolution. Employing sophisticated technological devices as well as the accumulated knowledge of the patterns of geological deposition, anthropologists are now able to pinpoint the most promising locations for fossil hunting more accurately. In the years ahead this will result in an enormous increase in the understanding of human biological history. Daniel Mo kari.