Evolution Is the Process by Which Organisms

Evolution is the Process by which organisms change over successive generations through the inheritance of new traits. During sexual reproduction, a complete set of DNA is donated from each parent organism. These two complete sets of DNA then mix together to create an entirely new set, discarding the remaining, giving rise to a new organism with a completely independent set of DNA. During the process, minor changes can occur in the makeup of the DNA, called mutations. These changes are the result of randomness, or chance mistakes which just happen to occur. Sometimes these mutations cause new traits to appear in the particular organism. If a new trait assists the organism in it's survival, then the organism will survive longer, reproduce more, and pass this particular trait along to more offspring. This is called "Natural Selection," it is nature selecting for the best new traits through survival. Sometimes new traits simply occur over time that are not survival mechanisms, but simply the result of random changes. For instance, changes in the sizes of certain anatomical features like horns, ears, or tails. When this occurs it is called "Genetic Drift."

The process of evolution is often said to work through Natural Selection, or in other words, the trait which aids survival in nature is what gets selected and passed on to succeeding generations. Over many generations these traits accumulate to cause changes in the organism; this is Evolution. An example can be made in the case of wolves, Canis lupus, as they spread around the world these animals developed different traits for survival in different environments. As a result, in nature, there are currently many different species of wolves which can trace their evolution back to a single source. (Vila, 1997) When humans interfere in this process, when they decide which traits will be chosen to be passed on to successive generations, then it is called "Domestication." (Morey, 1994)

When it came to the creation of man's best friend, the dog, for instance, Humans are thought to have began with wolves somewhere between 135,000 to 75,000 years ago choosing traits which were to be passed on and which were not. (Vila, 1997) By allowing the least aggressive, most tame and sociable among humans to reproduce, humans developed an entirely unique species: the dog, Canis familiaris. (Morey, 1994) From those beginnings, humans then continued to select for a variety of different traits creating more than 400 different breeds of dogs. Humans chose for physical traits like appendage size, shape of skull, or color, but also chose for behavioral traits like tameness, playfulness, herding, guarding, barking, or other traits that pleased their human masters. (Honeycutt, 2010)