Modern Synthetic Theory of Evolution

The modern synthetic theory of evolution represents a genuine synthesis of essentially every relevant biological discipline — genetics, ecology, comparative anatomy, biogeography and palaeontology were all drawn together to build a fuller account of how evolution actually works, one that gives due importance to both mutation and natural selection rather than favouring one over the other. Its principal architects include R. Fisher, J. B. S. Haldane, T. Dobzhansky, J. Huxley, E. Mayr, G. G. Simpson, G. L. Stebbins, Sewall Wright, Gregor Mendel and T. H. Morgan. In his own synthesis of the theory, Stebbins identified five key contributing factors — gene mutations, mutations affecting chromosome structure and number, genetic recombination, natural selection, and reproductive isolation — which together drive the evolution of new species.

• All the individuals of the same species constitute a population. Populations occur as small groups of 'interbreeding populations'; such a small interbreeding group is called a Mendelian population.
• The total genetic information encoded in the sum total of the genes of a Mendelian population is the gene pool - simply, the total number of genes of all the individuals of a population. The gametes produced by the individuals furnish the pool of genes of the next generation, from which genes are selected.
• Migration of a population effectively alters the gene pool; the gene pool also changes as one generation replaces another in the Mendelian population. Thus any change in the gene pool affects the population. …