"The Evolution of Genetic Covariance Between Traits as Result of Multigenerational Environmental Fluctuations"do O, IsabelaPleiotropy and linkage disequilibrium are the primary causes of the genetic covariance between different traits. This genetic covariance can affect the evolution of a population in many ways. Conversely, research has demonstrated the reciprocal effect of evolutionary processes in changing genetic covariances, in part through mutational patterns, correlational selection and plasticity. In this work we proposed that correlated changes in selective pressures over generations can cause evolution genetic covariance and G matrix in such a way that the population can in the future evolve faster. We use individual based simulations of populations exposed to three types of changing environments that differ in the correlation of the change between selective pressures. Our simulation experiments demonstrate that selection pressures for different traits changing in a correlated pattern over generations can lead to stronger trait correlations compared to the case with independently changing selective optima. Our findings show that correlated selective pressures result in significantly higher genetic trait covariance and that pleiotropy accounts for the majority of the difference in covariance between treatments. We also observe that the mutational variance evolves according to the environment that the populations were exposed to. Moreover, we show that clustered patterns of changes in selection can allow the evolution of genetic modularity. We show that the pattern of change in the selective environment affects the pace at which fitness evolves, with populations experiencing correlated change in optima having on average higher mean fitness than those experiencing uncorrelated environment change. |
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