Charles Darwin and Natural Selection

Charles Darwin wrote a legendary book titled On the Origin of Species by Means of Natural Selection. The three important ideas discussed in this book are the fact that evolution does actually occur, the theory that natural selection is the driving force behind evolution, and phylogeny, the concept that all forms of life are related to one another genealogically, through family roots. Darwin developed these ideas as a result of his experiences on the H.M.S. Beagle, a British surveying vessel. It sailed around the world on a mapping expedition during the 1830s. Darwin was the ship's naturalist; he recorded information about geology, sea life, plants, animals, and people the crew met along the way.

Darwin was twenty-two years old and a college grad on this voyage and greatly interested in natural science and history. He wanted to be a preacher because he thought it would allow him the free time to pursue his interests. Darwin was well-aware of the concept of evolution and knew that other researchers were debating its credibility.

Evolution had been a part of Western society for over 2,000 years, since the days of Aristotle, who explained that there were natural laws that told of how the world came about. These laws were meant to serve as alternatives to usual myths and stories about the origin of the universe. Aristotle believed that the world had "lower" and "higher" ranks of species, with the lower ones giving rise to the higher. Erasmus Darwin, one of Darwin's grandfathers, had even written extensively on the concept of evolution. During Charles Darwin's time, scientist and research jobs were becoming more professionalized, developing their own societies and holding regular meetings. These advances are what allowed the theory of evolution to become an actual scientific hypothesis.

During the middle 1800s, evolution proposed a debate to the notion that species were fixed and unchanging. This concept was called the Fixity of Species. The argument for this theory was based on the idea that the structure of each species was based on a model, ideal form. Every type of species was supposed to be an exact replica of its counterpart because everything was believed to be built in one definitive way. Everyone believed that there was no possibility for change.

Charles Darwin himself began wondering if species were fixed or prone to evolution. His 5-year experience on the Beagle collecting natural specimens had allowed him to become the best naturalist in the world at that time. He looked at species differently than other researchers; he thought that it was important that all species should have uniqueness in them even though they were the same in some respects. The first clue that made Darwin totally believe in the concept of evolution was the mockingbird. Darwin collected specimens of these birds in the Galapagos Islands and sent them back to London for study. At the end of the voyage, Darwin consulted a bird specialist by the name of John Gould concerning the origin of the mockingbird. Darwin learned that he had misclassified some of these birds because he was unable to tell the species apart from the subspecies. He could not tell their physical differences from one another, and this was due to the fixity theory. He realized that different traits between the species and subspecies would be better recognized if the subspecies developed a bit differently. He determined that this could be done by placing them in a different environment, in this case, a separate island. A second clue that made Darwin look into the evolution process

further was fossils. He had collected specimens of armor-plated beasts known as megatheres, and research led him to believe that they might be related to the armadillo.

Darwin's study of the evolution theory led him to develop the concept of natural selection, which has many different parts to it. More individuals are born into a species in every generation than the ones that actually live to reproduce; all individuals differ in structure and behavior, with many of these traits being inherited; some individuals have a greater ability to survive and reproduce because their traits are better adapted for them to survive in a particular environment; the rate at which offspring are produced is much faster than the environment in providing food, shelter, and other needs of survival. Therefore, the individuals which have traits that are better adapted to the environment with outlast all the others, creating differences in the species over time.

Darwin's development of the natural selection process is very important to science, even today. It allowed us to understand why there are differences within a species. It explains why one blonde-haired individual may have blue eyes, while another has green ones. I was always somewhat skeptical of Darwin's work, but after looking over these websites, it is very easy to see how important his studies are to the world of science.