FREE ESSAY ON EVOLUTION

EVOLUTION

The origins of mankind is an extremely controversial issue within today's society.
Scientists have a host of different theories pertaining to man's inhabitance of earth.
Many disagreements arise between scientists who have different beliefs pertaining to
where and how mankind arose. One such argument is the conflict involving the theory of
evolution versus the theory of creation. After extensive scientific research, it is
apparent that the theory of evolution is correct.
Evolution is the theory that life arose by natural processes at an early stage of the
earth's history and that complex organisms developed from simpler organisms by a process
of slow change (Coren 209). It's the idea that new species arise from older species after
thousands of years of gradual chemical, environmental, and genetic change (Coren 142).
Evolution can also be described as the complex processes by which living organisms
originated on earth and have been diversified and modified through sustained changes in
form and function ("Evolution"). Scientists, looking for an explanation to the origin of
man and other organisms created this evolutionism theory, which also presented answers to
the many asked questions dealing with similarities between species. Unlike the theory of
creation, which states that the complexity of life and different species can only be
explained in 
terms of a supernatural creator or god who placed life on earth, the theory of evolution
has a plethora of evidence proving it to be true ("Creation"). 
There are several different types of observations that support the theory of organic
evolution as an explanation for the similarities and the differences among species. One
such observation is in the geologic record. The geologic record is the rock scheme found
within the earth's outer crust. By means of radioactive dating, the ages of rocks in many
places on earth have been determined. It's a timetable of the earth's geologic history.
This combined with the fossil record, another observation supporting the evolutionary
hypothesis, has produced an apparent sequence of life forms from most simple to most
complex during the history of the planet. Fossils are any remains or traces of a
once-living organism, which are formed by preservation, petrifaction, or sedimentation.
Organisms can be preserved and protected against decay by being trapped in amber, tar, or
frozen in ice. The hard parts of an organism, such as shells or bones, can be preserved
when the flesh of an organism has decayed away. In other cases, materials of a dead
organism may be gradually washed away and replaced by minerals from the water causing the
organism to petrify, or harden. Imprints, molds, or casts left by an organism after it is
enclosed in sedimentary rock and decomposed are also fossils, as well as footprints and
tracks. The fossil record is the timetable of fossils found in within the earth's
geologic record. Since the upper layers of sedimentary rocks are assumed to have been
laid down over lower layers, the upper layers are younger than those deeper into the
earth. Therefore, fossils found within the upper layers 
are also younger than those found within the lower layers. This combination of geologic
and fossil records shows the progression of species as time also progressed (Coren 142).
In reiterating the definition of evolution, we are reminded that gradual changes in one
life form's anatomy, cytology, embryology, or biochemistry could cause for a new species
to originate. Similarities in these categories link species together and are therefore
studied to support evolutionism. In comparing anatomy, the structures of different
organisms often show unexpected similarities. Cell organelles, such as cell membranes,
ribosomes, and other structures found within cells, are also similar in organisms of all
kinds, showing that comparative cytology can also shows signs of evolution. When
comparing the embryos of different organisms, comparative embryology, similarities can be
seen in early stages of embryos that are completely different at maturity. Finally,
comparative biochemistry, which is the comparing of biochemical compounds, such as amino
acids, can also show similarities in species, reinforcing the idea of evolution (Coren
143). 
As curiosity rose throughout much of the world, scientists began to question the
existence of organisms and why some are so alike in so many ways and so diverse as well.
Several theories have been proposed in the past to account for the diversity and
similarity of species. One scientist by the name of Lamarck proposed that changes in
species occurred basically as the result of a striving of organisms for improvement. One
main point of this theory was use and disuse. New organs 
appear in a species as a result of a need for them, and they increase in size or
effectiveness through repeated use. Organs not needed decrease in size or strength as a
result of disuse. A second idea included in his theory was the transmission of acquired
characteristics. This means that a trait acquired during the lifetime of an organism,
including improvements of existing traits, can be transmitted to its offspring (Coren
145). Later in scientific history, it was Charles Darwin who came up with the most
convincing theories of adaptation and development. In 1859 he published The Origin of
Species, introducing the theory that species evolve from others, including man's
development from apes (Lampton 48). Darwin proposed that evolution occurred as the result
of natural selection. Natural selection is the process by which environmental effects
lead to varying degrees of reproductive success among individuals of a population of
organisms with different characteristics and traits. It's the idea that organisms with
favorable variations are better able to survive and reproduce than organisms not well
adapted ("Natural Selection"). Overproduction is a main idea of Darwin's theory. He
believes that more offspring are produced than can survive, because of limitations in
living space and food supply. He also believes in competition, where individuals of each
generation compete for available food and opportunities to mate and reproduce. A third
idea of Darwin's evolution theory is variation, meaning some individuals are better
fitted to survive than others, because of variations in characteristics. Survival of the
fittest was how he explained the fact that individuals better fitted to survive are more
likely to live longer and reproduce. Darwin's idea of transmission of 
favorable characteristics modified the earlier idea presented by Lamarck. Charles
believed offspring of the fittest individuals would inherit only the favorable variations
that enabled their parents to survive and reproduce (Coren 145). Explaining this idea,
Charles Darwin stated, "Beneficial variations of all kinds will thus, either occasionally
or habitually, have been preserved, and injurious ones eliminated" (Thomas 130). In the
end, Darwin expressed his idea on the evolution of species saying that the accumulation
of favorable variations will gradually lead to the appearance of new species better
adapted to their environment. Another scientist, DeVries, later added to Darwin's theory
that mutations were the source of new traits that permitted evolution to occur. These
scientists put together today's basis of thinking and questioning evolutionary processes
(Coren 145).
Once these new scientific explanations were introduced into the society, people began
questioning not only animal origins, but also the beginnings of mankind itself. Through
years of research, experimentation, and applying the theories of evolution, it has been
suggested that man derived from the ape, and there is an endless amount of evidence to
prove it. 
The first step in proving that man derived from ape is to compare the two organisms from
head to toe, and from anatomy to embryo development. Similarities between the two
organisms would provide some facts helpful in proving the humans and apes to be related.
In comparing anatomy, a multitude of 
similarities is present. Both human and ape have diversified teeth, meaning a variety of
tooth types such as molars, incisors, and canines. This also confirms that 
humans and apes are omnivorous, eating both meat and vegetables. Both lack an external
tail and both are capable of reaching an upright posture as well as bipedal locomotion,
walking on two legs. Humans and apes both have an appendix, which is an appendage that it
believed to be used for the digestion of rocks, sticks, and tree bark. Humans do not have
a need to digest rocks; therefore their appendix is fairly small and useless. The theory
of evolution would lead us to believe that human ancestors did have to digest stones and
needed a strong appendix, but as a result of disuse, the appendix in modern humans has
shrunken and weakened and is not needed. Other similarities in anatomy between man and
ape include, stereoptic vision, which is the ability to see in three dimensions, and
similarities in cranial structure. In comparative embryology, a similarity in the length
of the gestation period is observed. Fetal development in both humans and apes is between
250 and 280 days. In biochemistry, the two species reach sexual maturity between the ages
of 8 and 15 years due to the secreting of hormones. They also have similar blood types.
The most intriguing similarities are those that have to do with behavior and psychology.
Both man and ape have similar personality ranges. They interact in small social units,
families of two to six members, and they have the ability to invent their own culture,
for example, tool making (Moore 185).
Even with all of the information about similarities between man and ape, there is still
more evidence proving the theory of evolution. Determined and curious scientists,
archeologists, and anthropologists began to study the geologic and fossil records in
order to obtain actual remains of human ancestors. The fossil evidence 
for immediate ancestors of modern humans is divided into the genera Australopithecus and
Homo, and begins almost 5 million years ago. Australopithecus originated in Africa, which
was believed to be the place of origin of man's ancestors, and were most primitive. The
Genus Homo pertained to the more modern and complex ancestors who began to spread through
and eventually out of Africa ("Human Evolution"). Scientists' discoveries are hard
evidence supporting the evolution theory as well as helping to date the beginnings and
stages of mankind. One such discovery was the finding of Australopithecus Ramidus.
Ramidus, meaning root, is thought to be the missing link between man and ape. It was
given that name because it is the beginning of man, man's roots. Dated to be 4.4 million
years old, it is the oldest hominid, human ancestor, ever unearthed. Tim White, from the
University of California, discovered Australopithecus Ramidus in 1992, near Aramis,
Ethiopia. This hominid was more apelike than manlike, but not completely ape (Thomas
136). An amazing discovery that had a large impact on the scientific world of evolution
was the discovery of Lucy. Lucy was Australopithecus Afzrensis that dated back 3.5
million years. Found by paleoanthropologist, Donald Johanson, in Hadar, Ethiopia, on
November 30, 1974. The reason why it was such a huge find was because the 3 ? foot tall
female hominid skeleton was the most complete, best preserved skeleton of any
erect-walking human ancestor that has ever been found. The completeness allowed for an
accurate idea of how she should have been pieced together, what she looked like, and how
old she was (Johanson 86). Until the discovery of Lucy and Australopithecus Ramidus, the
oldest known human ancestor 
was Australopithecus Africanus, known as the Southern Ape from South Africa (Thomas 136).
It was a little more than 3 million years old and was thought to be the missing link
until the later discoveries (Lemonick 82). Raymond Dart discovered Australopithecus
Africanus near Tuang, South Africa, in 1925 (Thomas 69). Another important finding was of
ER-1470. ER-1470 was the oldest known Homo, Homo Habilis. Named after its discovery
sight, ER-1470 was the oldest most complete representative of Homo Habilis. Richard E.
Leakey located the skeleton near Lake Turkana in Kenya. It was named Homo Habilis because
that meant skillful person. The 1.8 million old skeleton featured a large cranial
capacity, meaning it was more intelligent than the older ancestors, a compact face, and
small teeth. This species had grown a foot and a half since Lucy, reaching 4 1/2 to 5
feet tall. Its cranial capacity was 50 cubic inches, which was also a great amount larger
than the older ancestors. Homo Habilis was the first to use tools, which were found, at
the site. That's just another reason for its title of skillful person (Thomas 140).
Before Homo Sapiens, modern day humans, there was the Neanderthal Man. Its discovery was
also extremely important discovery because of its young, 1 million-year-old age.
Discovered in a small cave in the Neander Valley near Dusseldorf, Germany, Homo
Neanderthalensis was 5 ? feet tall with an even larger cranial 
capacity than Homo Habilis. Neanderthals made tools and controlled fire, two major
achievements for primitive man (Thomas 44). These discoveries make up the strong evidence
proving the theory of evolution.
As more and more discoveries of primitive skulls and bones of human ancestors were made,
an evolution scale could be created. The scale is a timeline of human ancestors beginning
at the most apelike and moving to the most humanlike until the modern day human is
finally reached. Starting 4.4 million years ago was Australopithecus Ramidus and ending
with Homo Sapiens Sapiens, the anatomically modern human being. As the scale moves from
oldest hominid to youngest, the species become taller, more erect in their posture, and
their cranial capacity increases, indicating a increase in intelligence (Lemonick 82).
These facts are just more evidence supporting the evolution theory.
As scientists attempted to prove their ideas of adaptation and development, others still
believed in the idea of creation. On May 7, 1925, in Tennessee, a popular schoolteacher
by the name of John Scopes was arrested. He was charged with teaching the theory of
evolution to his class on April 24. In court, Scopes' strong defense penetrated the
prosecution's case when they stated that the Bible could not always be taken literally
and that there was no way the world could have been created in six days. Even though
Scopes was found guilty of contradicting creationism and the Bible's teachings, the
persuasion of the defense's case brought up the major question of evolution versus
creation. In 1996, the issue was revisited 
and now teachers have the right to teach both theories. The Attorney General said the
constitutional separation of church and state would be violated if both theories were not
acceptable. This trial was a major step for those who believed in evolution. 
The outcome eventually allowed for people to open their eyes and accept new ideas. The
theory of evolution proved to be true ("Monkey").
The controversy over whether evolution or creation is the correct answer to human origins
is a major topic of discussion and argument in today's society. People are entitled to
their beliefs, but a great deal of evidence and supporting information has confirmed the
theory of evolution to be factual and accurate. By combining all of this information
along with comparisons between man and ape and the discoveries of humanlike fossils, the
truth is apparent. The theory of evolution is correct.