SEXUAL SELECTION Meaning and
Definition
-
Sexual selection refers to a mechanism for evolutionary change that primarily occurs through the influence of certain traits on an organism's ability to secure mates and reproduce. It is a branch of natural selection that operates specifically on characteristics that enhance an organism's reproductive success, rather than solely on the ability to survive.
In sexual selection, certain individuals possess traits that are deemed attractive or preferred by potential mates. These traits can be physical features such as bright colors, distinctive patterns, or elaborate ornaments, as well as behavioral traits like courtship displays or vocalizations. The individuals possessing these favored traits may have a higher chance of finding mates, mating more frequently, or having better reproductive success.
This process can lead to the evolution of exaggerated, often conspicuous characteristics that may not necessarily contribute directly to survival. These traits are further refined and passed on to successive generations, gradually creating more pronounced differences between sexes or populations.
Sexual selection can work in two principal modes: intersexual selection, involving competition between individuals of one sex for access to mates of the opposite sex, and intrasexual selection, involving competition among individuals of the same sex for mating opportunities. These two modes often interact and can lead to distinctive social behaviors, mating rituals, and morphological variations.
Overall, sexual selection plays a pivotal role in shaping the diverse reproductive strategies and physical traits observed among organisms, contributing to the vast array of species we see in nature.
Etymology of SEXUAL SELECTION
The word "sexual selection" was coined by Charles Darwin in his book "The Descent of Man, and Selection in Relation to Sex" published in 1871. Darwin used the term to describe the process through which certain traits or behaviors evolve as a result of individuals within a population choosing mates based on those traits. The term combines the words "sexual", relating to reproduction or the sexes, and "selection", referring to the process of choosing or selecting. Darwin's theory of sexual selection has since been widely accepted and studied in the field of evolutionary biology.
