The origin of species

For more than 20 years, Darwin collected evidence to support his theory and refined his ideas. He delayed publishing his ideas until 1858, when Alfred Russel Wallace sent him a letter describing a theory of evolution identical to Darwin’s own. Wallace was a British naturalist who had worked in the Malay Archipelago for eight years. He concluded from his research that some organisms live while others die because of differences in their characteristics, such as their ability to resist disease or escape predation. Darwin and Wallace published a paper jointly describing their theory of evolution by natural selection. However, Darwin’s name has become more strongly linked with the theory because of a book he published on 24 November 1859. The book, entitled “The Origin of Species by Means of Natural Selection or the Preservations of Favoured Races in the Struggle for Life”, has been called the most important biology book ever written. It not only gives a full description of the theory of evolution by natural selection, but also contains a huge mass of evidence to support the theory.

The reaction to Darwin.

Many people found it difficult to accept Darwin’s ideas, especially the idea that modern humans and apes are probably descended from a common ancestor. However, his theory is supported by so much evidence that the majority of biologists accept it. Evolution by natural selection has become a central theme which underpins much of modern biology. The modern theory of evolution is called neo-Darwinism because it incorporates new scientific evidence, particularly from genetics and molecular biology. For example, we know that the variations that are so important in natural selection come about by random and spontaneous changes in genes, particularly from mutations in reproductive cells. Despite modifications to Darwin’s theory in neo-Darwinism, natural selection is still the driving force behind evolution, or the theory of evolution by the natural selection of inherited characteristics.

Natural Selection