Neutral additive genetic variance in a metapopulation

Additive Genetic Variance

Metapopulation patterns of additive and nonadditive genetic variance in the sea bass (Dicentrarchus labrax)

Describing and explaining the geographic within-species variation in phenotypes ("phenogeography") in the sea over a species distribution range is central to our understanding of a variety of eco-evolutionary topics. However, phenogeographic studies that have a large potential to investigate adaptive variation are overcome by phylogeographic studies, still mainly focusing on neutral markers. Ho...

Effect of genetic groups on estimates of additive genetic variance.

This study examined the effect of genetic grouping on REML estimates of additive genetic variance with an animal model with selected base populations. A simulated population of 40 animals (20 males and 20 females) was followed under selection or random mating conditions for 10 generations. Each population was replicated 20 or 50 times. Genetic grouping reduced estimates of additive genetic vari...

Estimation of additive genetic variance when base populations are selected.

A population of size 40 was simulated 1,000 times for 10 generations. Five out of twenty males were selected each generation, and each male was mated to four females to have two progeny. The additive genetic variance (sigma 2a) before selection was 10, and the initial heritability was .5. Due to covariances among animals, inbreeding and gametic disequilibrium, the genetic variance was reduced t...

Sexual selection, additive genetic variance and the "phenotypic handicap".

Fisher (1958) proposed “runaway” sexual selection to explain female preference for males bearing exaggerated, seemingly deleterious traits, such as bright coloration or otherwise useless ornamentation. In Fisher’s model, females selecting males bearing extreme traits gain an advantage because they produce attractive sons which are, in turn, preferred by females. Zahavi’s (1975) counterproposal,...