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Theory of Evolution

Brett Ramirez
The primary author is the individual who drafted the first version of this section; a section that could have been modified since it was originally published.

Australopithecus Sediba: The First Human Ancestors

The beginning of evolution started much before the first human ancestors walked the planet Earth. However for the purposes of this research, let us start with the first human ancestors; Australopithecus Sediba, a species of Australopithecus that was discovered in a remote part of the Malapa Nature Reserve in north Johannesburg in early 2008. The remains discovered date back nearly two million years. These remains represent the closest relation to the present-day humans discovered to date.

The remains discovered were of a young male juvenile, who stood just slightly over 4 feet tall. These remains have the earliest recognizable forms of present day hominid brain capacity, foot and ankle bones as well as pelvic bones. It is because of these similarities that they are considered the oldest human ancestors ever discovered.

The studies performed on these early ancestors have shown that they are just as different from present day humans as they are alike. For example, because of the shape of their shoulders, our ancient ancestors would have had a very difficult time running for extended periods of time as we can do today. Rather, they were more inclined to climb using their elongated arms, making them very proficient climbers. While they may have not gotten around like we do now, they do exhibit signs of similar knee, hip, and back structures that are seen in present day humans.

Ancient Theories

To explain how the ancient world pictured evolution, put into perspective the way they thought of the world around them.

Considering how the Incas reacted to a lunar eclipse serves as a perspective into the way of thought in the ancient world. The Inca believed that a lunar eclipse was the product of a jaguar attacking the moon and to protect the moon they began yelling and howling at the sky while commanding all their animals to do the same. They believed that because they did this, the jaguar got scared and the moon returned to normal.

Ancient people did not have the same knowledge of the universe we do today. Today we know that a lunar eclipse is the result of the moon crossing paths with the sun; not because a jaguar is attacking. The eclipse will end without any action from Earth.

In the ancient world, the major belief was that if evolution was real, it was because it was directly sent from the Gods. Nature evolved because that is what the Gods wanted for the world. The Gods controlled everything that happened in the world. This was the major belief system until Charles Darwin published The Origin of Species.

Charles Darwin: The Theory of Evolution

Famous for writing Origin of Species in 1859, Charles Darwin was the founder of the theory of evolution. Darwin became internationally famous because of these ideas which have become generally accepted.

Although his ideas were not accepted at the time of their conception, Darwin is considered as one of the single most influential people in all of human history. It was not until the 1930s when modern evolutionary synthesis created a general agreement that natural selection was the driving force behind evolution.

Darwin says that new species come gradually over time. The less fit species will not survive because competition for survival is always fierce. The surviving species reproduce only favorable traits as the weak traits do not survive long enough to reproduce. Over millions of years, everything around us from plant life to animal life has evolved from each other which means that every living thing in the world are related at the molecular level.

In the natural selection process, over long spans of time, an offspring will be born with an altered trait, this trait will either increase the organism's chance of survival and thus be passed on to the next generation. If a trait is detrimental to the survival of the organism, it will not be passed down to the next generation. This is how new species are evolved from previous species.

A quick example of this can be seen in the difference between the bear population. Brown bears were once the dominant species of bear in the world; until at some point in history one bear was born with white hair. This white hair gave the bear an advantage when hunting in the snow because it was harder for prey to see them coming. This gene is then passed on to the next generation. Eventually white bears dominated the northern polar regions of the world pushing the less prepared brown bears south where they use their brown fur to blend into the forests.

Darwin's Galapagos Islands

Some of Charles Darwin's first work was done on the Galapagos Islands which are located off the coast of Ecuador in the Pacific Ocean. They were, at the time of Darwin, very rarely visited by travelers because of their remote location and harsh desert like conditions. Darwin was the first person to begin to study these islands and the creatures that inhabited it. Brad Page's "Charles Darwin and His Finches" goes into detail about Darwin's study of the Galapagos Islands.

At the time of his study, Darwin was just a young man who had just left medical school at Edinburgh and was searching for inspiration. He studied how each species of animal had specific adaptations that made them flourish on their islands. Particularly he studied the islands finches and tortoises, which he explains later on in his famous book, Origin of Species.

Thomas H. Huxley: The Evidence

Thomas Huxley has become known as "Darwin's bulldog" because he was such an advocate for Darwin's work in the theory of evolution. Huxley was, however, slow to accept some of the most extreme ideals of Darwin such as natural selection. Huxley did, though, publically fully support Darwin and was also very important in creating scientific learning in the schools starting in Britain and expanding world-wide.

Huxley also was key in developing the term "agnostic" which describes argues that it is impossible to know for sure whether or not there is or is not a God.

Evolution vs. Creation Science

The debate between evolution and creationism or creation science is ongoing and may never reach an actual conclusion. When considering this debate, it is important to keep in mind that creationism is not against modern science; it simply takes into an account that evolutionary changes are due to the powers of a creator God.

One of the biggest debates is how the universe came into existence. The theory of the big bang is universally accepted. However it is the details of this event that are controversial. A pure evolutionist would say that the big bang was the product of matter exploding into everything we see today; something that happened simply by chance. A creationist would argue that these atoms exploded together because of the work of a higher creational power known as God.

An evolutionist would also argue that the physical evidence we see in geology—the study of rocks and rock formations—explain the age of the earth. Evolutionists believe the Earth is somewhere around 4.5 billion years old. Creationists believe that the origins of all species can be traced back to an event explained in the Bible as the great flood. In the great flood, God flooded the Earth and instructed Noah to build an Ark which would protect animals. Creationists argue that, based on this event, that the Earth is less than 10,000 years old.

Works Consulted