Dataset Information

Fitness consequences of maternal and grandmaternal effects.

ABSTRACT: Transgenerational effects are broader than only parental relationships. Despite mounting evidence that multigenerational effects alter phenotypic and life-history traits, our understanding of how they combine to determine fitness is not well developed because of the added complexity necessary to study them. Here, we derive a quantitative genetic model of adaptation to an extraordinary new environment by an additive genetic component, phenotypic plasticity, maternal and grandmaternal effects. We show how, at equilibrium, negative maternal and negative grandmaternal effects maximize expected population mean fitness. We define negative transgenerational effects as those that have a negative effect on trait expression in the subsequent generation, that is, they slow, or potentially reverse, the expected evolutionary dynamic. When maternal effects are positive, negative grandmaternal effects are preferred. As expected under Mendelian inheritance, the grandmaternal effects have a lower impact on fitness than the maternal effects, but this dual inheritance model predicts a more complex relationship between maternal and grandmaternal effects to constrain phenotypic variance and so maximize expected population mean fitness in the offspring.

SUBMITTER: Prizak R

PROVIDER: S-EPMC4161186 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Fitness consequences of maternal and grandmaternal effects.

Prizak Roshan R Ezard Thomas H G TH Hoyle Rebecca B RB

Ecology and evolution 20140719 15

Transgenerational effects are broader than only parental relationships. Despite mounting evidence that multigenerational effects alter phenotypic and life-history traits, our understanding of how they combine to determine fitness is not well developed because of the added complexity necessary to study them. Here, we derive a quantitative genetic model of adaptation to an extraordinary new environment by an additive genetic component, phenotypic plasticity, maternal and grandmaternal effects. We ...[more]

PMID: 25247070

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Dataset Information

Fitness consequences of maternal and grandmaternal effects.

Publications

Fitness consequences of maternal and grandmaternal effects.

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