Describe how selection at a locus can result in a loss of polymorphism surrounding the locus.

Key Concepts

Genetic Polymorphism

Genetic polymorphism refers to the occurrence of two or more distinct alleles at a locus within a population. This variation is crucial for the adaptability and evolution of species, as it provides a genetic reservoir that can be acted upon by natural selection. When polymorphism is high, it indicates a diverse gene pool, which can enhance survival in changing environments.

Selection Pressure

Selection pressure is the environmental factor that influences the survival and reproduction of individuals within a population. It can be natural, sexual, or artificial, and it favors certain traits over others. When selection pressure is applied to a specific locus, alleles that confer advantageous traits may increase in frequency, while less favorable alleles may diminish, leading to a reduction in overall genetic diversity.

Genetic Hitchhiking

Genetic hitchhiking occurs when an allele at one locus increases in frequency due to selection for a nearby beneficial allele, even if the hitchhiked allele itself is neutral or deleterious. This phenomenon can lead to a loss of polymorphism around the selected locus, as alleles linked to the advantageous trait are also swept along, reducing genetic variation in that region of the genome.