Competition and Adaptation Among Diploid and Polyploid Clones of Unisexual Fishes
During the development of population biology as a science, genetic variation has been regarded as adaptive, maladaptive, or simply waiting to be drawn upon during times of environmental change. Attempts to evaluate the importance of variation, either in the production of heterosis or as adaptive polymorphisms in homogeneous, heterogeneous, or fluctuating environments, are generally confounded by two major problems: (1) identifying the forces of selection that are operational and (2) determining the phenotype (and associated genotype) upon which selection operates. In sexually reproducing organisms the effects of selection are continually obscured by recombination. Asexual organisms provide a simpler system for investigating the adaptive significance of genetic variation. Here, the genetic variation of a population is contained in the form of multiple genetic clones that, in the absence of recombination, magnify the effects of selection in successive generations.
KeywordsParental Species Brood Size Crowded Condition Large Brood Growth Rate Difference
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