Gene flow can decrease when a species moves to a new environment and has low fitness. This causes maladaptation of the species in their new environment (Garant et. al 2007:437). This leads to many theories about gene flow in nature and is the logic of ecological speciation (Garant et. al 2007:437). For one, the rate of dispersal showed be higher than the rate of gene flow, which is the case among many groups. Examples of this have been seem among pea aphid Acyrthosiphon pisum and in sockeye salmon Oncorhynchus nerka. With the pea aphid it was clear that the reason for this was the choice against maladapted migrants and hybrids. Secondly, “greater divergent selection should lead to greater adaptive divergence and hence lower gene flow” (Garant et. al 2007:437). There have been several studies to go along with this statement that show how “natural populations have found that measures of divergent selection or adaptive divergence are negatively correlated with measures of gene flow” (Garant et. al 2007:437). Apparently it is not also evident, and the necessary conditions needed are
Gene flow can decrease when a species moves to a new environment and has low fitness. This causes maladaptation of the species in their new environment (Garant et. al 2007:437). This leads to many theories about gene flow in nature and is the logic of ecological speciation (Garant et. al 2007:437). For one, the rate of dispersal showed be higher than the rate of gene flow, which is the case among many groups. Examples of this have been seem among pea aphid Acyrthosiphon pisum and in sockeye salmon Oncorhynchus nerka. With the pea aphid it was clear that the reason for this was the choice against maladapted migrants and hybrids. Secondly, “greater divergent selection should lead to greater adaptive divergence and hence lower gene flow” (Garant et. al 2007:437). There have been several studies to go along with this statement that show how “natural populations have found that measures of divergent selection or adaptive divergence are negatively correlated with measures of gene flow” (Garant et. al 2007:437). Apparently it is not also evident, and the necessary conditions needed are