Chapter 13 - Epigenetics of Sympatric Speciation—Speciation as a Mechanism of Evolution

Abstract

While in allopatric speciation the reproductive isolation is determined externally by the spatial isolation of populations, during sympatric speciation particular groups of individuals create separate mating systems with self-like individuals while sharing the same habitat with the rest of the original population. Reliable evidence indicates that sympatric speciation not only occurs but, most likely, is the main form of speciation in nature. Formation of separate mating systems in sympatry is based on the ability of individuals in a population to change mating preferences and signaling traits and choose as mating partners individuals with the changed signaling traits. Mating preferences of the choosing sex and signaling traits of the opposite sex form the mating recognition system on which formation of the separate mating system and the reproductive isolation in sympatry is based. No changes in genes are involved in formation of these reproductively isolated groups and in sympatric speciation in general. Sympatric speciation is intrinsically determined by neurocognitive processes taking place in neural circuits that determine the mating behavior and mating preferences.