Darwin is considered the father of evolution. In truth, Darwin arrived at his theory of evolution at the same time another scientist, Alfred Russell Wallace, came to the same conclusion. However, Darwin was a respected scientist even before he wrote On the Origin of Species, while Wallace was relatively unknown, so people were more inclined to listen to Darwin. Origin enjoyed immediate success: its first printing sold out immediately and a second printing following a month later. Darwin's ideas found their way out of the scientific world and into the business world and even society itself. In many senses, Darwin's theories created a societal transformation.
Darwin's theory consisted of two main points; 1) diverse groups of animals evolve from one or a few common ancestors; 2) the mechanism by which this evolution takes place is natural selection. This SparkNote will first take a look at Origin of the Species, and then more closely examine Darwin's theories. Darwin's theory of evolution, also called Darwinism, can be further divided into 5 parts: "evolution as such", common descent, gradualism, population speciation, and natural selection. Types of natural selection are discussed in the Natural Selection SparkNote, and types of speciation are discussed in the Speciation SparkNote. The modern understanding of the process of natural selection is discussed in further detail in Synthesis of Darwin and Genetics.