FISHERIAN RUNAWAY Meaning and
Definition
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Fisherian runaway, also known as the Fisherian process, is a concept derived from evolutionary biology and population genetics. It refers to a theoretical model proposed by British statistician and geneticist Ronald Fisher in the early 20th century to explain the evolution of conspicuous, sexually-selected traits in certain species.
In Fisherian runaway, a positive feedback loop occurs between a particular trait that is preferred by one sex (usually the female) and the preference for that trait in the opposite sex (usually the male). Initial genetic variation in the trait leads to some individuals possessing slightly more exaggerated or elaborate versions of the trait, which enhances their chances of mating. This, in turn, creates a selective advantage for individuals who possess the trait, leading to its increased prevalence in subsequent generations.
The runaway process is self-reinforcing and can lead to an "arms race" in which both sexes continuously evolve more extreme versions of the trait and preference, respectively. Ultimately, this can result in the development of extravagant and seemingly impractical traits, such as the elaborate plumage of male peafowls or the impressive antlers of male deer.
The Fisherian runaway mechanism has contributed to our understanding of sexual selection and the evolution of exaggerated traits, shedding light on the intricate dynamics between reproductive success, genetic variation, and mate choice. By studying this process, scientists gain insights into the formation and persistence of some of nature's most visually striking and flamboyant displays among various animal species.
