How We Evolved into Homo Sapiens
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How We Evolved into Homo Sapiens
Uneducated people who believe in evolution have a pretty vague idea of what caused the human
race to have the appearance it has today. There is more to the story of human evolution than saying that
primitive monkeys somehow evolved into brutish Neanderthals, learned to use fire, made up a common
language, and eventually became modern humans. It is a long story of species who endure set backs and
breakthroughs in evolving for survival.
The dawn of apes is recorded at approximately 33 million years ago. Primates, such as
Aegypiopithecus, came to populate areas in northern Africa during the Oligocene epoch. About 30 million
years later, the Australopithecus genus began to populate similar areas in Africa. The time between these
two genus is filled with much uncertainty. However there have been some suggested ancestors that
appeared at various times between about 8 and 20 million years ago: Pronconsul and Kenyapithecus
(Kenya), Rampithecus and Sivapithecus (India, Pakistan, China, Kenya), Rudapithecus and Dryopithecus.
Some of the apes evolved into a different form, that of Australopithecus afrensis. This species
existed from about 3 million B.P. (before present) to about 2 million B.P. The first example of this species
was Lucy, a skeleton discovered by Donald C. Johanson in north-central Ethiopia. By finding bits of an
arm, part of a pelvis, a couple vertebrae, pieces of a jaw, and some ribs, Johanson was able to determine
that the skeleton was that of a female about 1.1 meters tall weighing about 30 kg. From the reconstructed
skull, it was determined that Lucy still had apelike facial features: a low forehead, a bony ridge over the
eyes, a flat nose, and no chin. Their cranial capacity is estimated at 375 to 500 milliliters compared to the
average 1350 ml of modern man. Being this primitive, their brains did not have the necessary areas for
The most important thing they learned from Lucy’s skeleton was that her pelvis and knee joints
allowed her species to walk with an erect bipedal stride millions of years before any other primate species.
This made A. afrensis more efficient allowing them carry food and materials where they needed to go. It
also allowed them to scavenge meat from predators more quickly with less risk of getting caught.
At the same time another species that has the same genus, Australopithecus africanus, dominated
South Africa from about 3 million to 2 million B.P. Very similar to A. afrensis, A. africanus had only a
slightly increased body size and cranial cavity. The brain was still however not advanced enough for
The next species of Australopithecus were robustus and boisei which existed from about 3 million
B.P. to 2 million B.P. Found in South Africa and Eastern Africa (respectively), these two share similar
cranial capacity, about 530 ml, and body structure, having a heavier and more powerful body than A.
afrensis and africanis. Both also had extremely power full jaws for eating hard shelled fruits and fibrous
roots. They also both used bone tools for digging and scavenging. Though both A. robustus and A. boisei
seem to be candidates for ancestors, they are believed to be evolutionary dead ends. There is however
another more likely relative that existed and competed with them during this time.
Homo habilis also existed in the same time frame in the Olduvai region of Africa. On average,
they were about 5 ft. tall and weighed under 100 lbs. This species had increased brain power, a cranium of
680 ml. It also contained the portion of the brain essential for speech. Although articulate speech did not
likely develop until perhaps 300,000 to 400,000 years ago, H. habilis were well on their way to increasing
their communication ability. A larger brain also allowed them to develop some primitive stone tools used
to butcher leftovers from predators’ kills quickly. From these tools, scientists were able to start studying
the culture and behavior of H. habilis. Tools made from material foreign to the region suggest that they
were able to travel and carry quantities of material efficiently.
Around 2 million years ago, H. habilis evolved into a stronger variety of human, Homo erectus.
Specimens of this species include Java man from the Dutch East Indies (Indonesia), Peking man found in
China, and other various
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Human evolution, Lower Paleolithic, Prehistoric Indonesia, Humans, Transitional fossils, Homo erectus, Homo habilis, Homo, Australopithecus, Anatomically modern human, Neanderthal, Java Man
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