How Man Evolved Essay, Research Paper

World History Human Evolution

Final Copy

January 19, 97

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 human

beings. 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 he

leaded to us, Homo Sapiens A lot of fossils, bones, and teeth have been found at various

places throughout Africa, Europe, and Asia that proved that early man existed. Tools

made of stone, bone, and wood have also have been discovered and excavated. As a result

of these discoveries, a idea of human evolution during the past 4 to 5 million years has

shown.

Most of the ability to make and use tools and other objects comes from the large size

and complexity of the human brain. through human evolution the size of the brain has

tripled. 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 human

evolution. They began to move into the tropical areas of Eurasia sometime after a million

years ago, and into the tropical parts of these continents about 500,000 years ago. Later

hominids were able to cross the water barrier into Australia. It is likely that the increase in

brain size took place to permit our ancestors to be increasingly able to live in a variety of

environments.

The third major trend in hominid development is the decrease in the size of the face and

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teeth. All of the apes are equipped with large teeth that were bigger than humans. The

earliest hominid remains had great teeth that project slightly, but those of all later hominids

show a great decrease in size. With these changes is a reduction in the size of the face and

jaws. As the teeth became smaller and the brain expanded, the face became smaller and its

position changed.

Between 7 and 20 million years ago, early apelike animals were greatly spread out on

the African and, later, on the Eurasian continents. Although many fossils, bones and teeth

have been found, the way of life of these mammals, and their evolutionary alikeness to the

living apes and humans are still a question to scientists. None of the fossils apes give signs

of being related directly towards us.

The fossils for human evolution begins with Australopithecus. Fossils of this primate

have been discovered in a lot of sites in eastern and southern Africa. The genus seems to

have become extinct about 1.5 million years ago and were found 4 million years ago. All

the australopithecines walked on two legs and gave the appearance of hominids. Their

teeth, jaws, and brain size are different from themselves and force a separation into four

groups; afarensis, africanus, robustus, and boisei.

The earliest australopithecine is afarensis, which lived in eastern Africa between 3 and 4

million years ago in Ethiopia and in Tanzania. Afarensis had a brain size a little larger than

chimpanzees. Some of them had dog teeth longer than later hominins. No tools have been

found with afarensis fossils. Between about 2.5 and 3 million years ago, afarensis evolved

into a later australopithecine, africanus. Known from sites in southern Africa, africanus

had a brain similar to afarensis. As with afarensis, no stone tools have been found with

africanus fossils.

Many scientists believe that there was an evolutionary split that led to robust

australopithecines, africanus evolved into the group Homo. This must have happened

between 1.5 and 2 million years ago. Fossils from this time show a mixture of traits. Some

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have large brains and teeth. Others have small, Homo-sized teeth and also small

australopithecine brains. Skulls and jaws from this period have been placed in the category

Homo 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 stone

tools, but also animal bones with scratch marks that experiments show were left by knife

marks. This shows that by this time early hominids were eating meat.

Evidence of a large-brained, small-toothed man known as Homo Erectus was found

1.5 million years ago. Homo Erectus grew into the tropical areas of the Old World, and at

the end of its evolution, into the warmer parts of Asia. A lot of archaeological sites from

the time of Homo Erectus show an advancement in toolmaking than was found at the

earlier sites. At the cave site of Peking man in north China, there is proof that fire was

used. These studies suggest that hominid behavior was becoming more advanced and

efficient. Throughout the time of Homo Erectus the movements in human evolution

continued. The brain sizes of early Homo Erectus fossils are larger than those of previous

hominids. 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 looks

with modern humans. New evidence tells that modern man, Homo Sapiens , first appeared

more than 90,000 years ago. There is disagreement with scientists on whether the hominin

fossils show a relation to the first appearance of Homo sapiens to humans. The

Neandertals (named from the Neander Valley in Germany) occupied some parts of Europe

and the middle east from 100,000 years ago until about 35,000 to 40,000 years ago, when

they disappeared.

The arguement over the Neanderthals also asks the question of the origins of human

populations, or races. Human populations are shown by a lot of physical differences. Most

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of these differences show adaptations to environmental conditions. The Neandertals and

other early Homo sapiens are seen as descending from Homo erectus and are ancestors to

modern humans.

Other scientists see racial differences n as a recent occurance. The features of the

Neandertals are a low, sloping forehead and a large face without a chin. They are too

primitive for them to be considered the ancestors of modern humans. According to this

theory, the begginings of modern humans can be found in Southern Africa or the Middle

East. Evolving 90,000 to 200,000 years ago, these humans then spread to all parts of the

world, supplanting the local, earlier Homo sapiens populations. In addition to som fossil

finds from southern Africa, support for this theory comes from comparisons of DNA, a

DNA form inherited only from the mother, taken from women distributing 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.

Whatever the outcome of thisdisagreement, the evidence shows that early Homo sapiens

groups 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 dead

deliberately, the bodies sometimes being accompanied by stone tools, by animal bones, and

even by flowers.

Although the features of today’s people did not change human history, some changes

did 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. About

10,000 years ago, one of the most important events in human history took place, plants

were farmed, and soon after, animals were used. This made it possible for humans to

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civilize.

Every thing we know we got from fossils, but we still don’t know enough. The future

fossil 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 result

in an enormous increase in the understanding of human evolution.

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