Conservation genetics

Conservation genetics is an interdisciplinary subfield of Population Genetics that aims to understand the dynamics of genes in populations principally to avoid extinction. Therefore, it applies genetic methods to the conservation and restoration of biodiversity. Researchers involved in conservation genetics come from a variety of fields including population genetics, molecular ecology, biology, evolutionary biology, and systematics. Genetic diversity is one of the three fundamental levels of biodiversity, so it is directly important in conservation. Genetic variability influences both the health and long-term survival of populations because decreased genetic diversity has been associated with reduced fitness, such as high juvenile mortality, diminished population growth, reduced immunity, and ultimate to higher extinction risk.

Genetic diversity is the variability of genes in a species. A number of means can express the level of genetic diversity: observed heterozygosity, expected heterozygosity, the mean number of alleles per locus, or the percentage of polymorphic loci.

Since the genes encode the information of the phenotype, genetic diversity determines the potential fitness of a population and ultimately its long-term persistence. Extinction risk has been associated with low genetic diversity because several researchers has documented reduced fitness in population with low genetic diversity. For example, low genetic diversity as low heterozigosity has been associated with low juvenile survival, reduced population growth, low body size, diminished adult lifespan.

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