Natural Selection

Natural Selection         Natural selection is a theory that Charles Darwin wrote about in the 19th Century. Many people criticized Darwin during this time but it was not something new. Galileo was placed under house arrest for his heliocentric theory. Many members of the church criticized Darwin's theory and so did many older scientists. However, many younger scientists believed Darwin, partly because they had come to the same or similar conclusions.                 Darwin thought that natural selection was caused by three main ideas. The first in that natural selection in which varieties occur spontaneously by chance but are the "selected for" because they are aids to survival. The second is that direct action of the environment in which non-adaptive varieties do not survive because of climate, food conditions, or the like. The third idea was the effects of use or disuse of variation. This means things such as the short beak of a bird versus a longer beak.

        Darwin took most of his information from breeders of pigeons, livestock, dogs and horses. Even though this information was not exactly scientific it still showed that humans could change many characteristics of a species. Darwin's goal was to prove that the same thing happened to animals but this time by natural selection. Varieties of animals are important for natural selection. Markings, coloration, size or shape of appendages, organs, or bodies are all types of varieties that Darwin related to natural selection. Even though at the time of this discovery of his, he had no idea what the use of these varieties were.

        Natural selection is a very simple concept and can be understood if one would think about certain simple things. Animals, plants and humans live in certain places. Animals live in different places due to their ability to survive in different...