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Genetic constraints predict evolutionary divergence in Dalechampia blossoms.

ABSTRACT: If genetic constraints are important, then rates and direction of evolution should be related to trait evolvability. Here we use recently developed measures of evolvability to test the genetic constraint hypothesis with quantitative genetic data on floral morphology from the Neotropical vine Dalechampia scandens (Euphorbiaceae). These measures were compared against rates of evolution and patterns of divergence among 24 populations in two species in the D. scandens species complex. We found clear evidence for genetic constraints, particularly among traits that were tightly phenotypically integrated. This relationship between evolvability and evolutionary divergence is puzzling, because the estimated evolvabilities seem too large to constitute real constraints. We suggest that this paradox can be explained by a combination of weak stabilizing selection around moving adaptive optima and small realized evolvabilities relative to the observed additive genetic variance.

SUBMITTER: Bolstad GH

PROVIDER: S-EPMC4084540 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Genetic constraints predict evolutionary divergence in Dalechampia blossoms.

Bolstad Geir H GH Hansen Thomas F TF Pélabon Christophe C Falahati-Anbaran Mohsen M Pérez-Barrales Rocío R Armbruster W Scott WS

Philosophical transactions of the Royal Society of London. Series B, Biological sciences 20140801 1649

If genetic constraints are important, then rates and direction of evolution should be related to trait evolvability. Here we use recently developed measures of evolvability to test the genetic constraint hypothesis with quantitative genetic data on floral morphology from the Neotropical vine Dalechampia scandens (Euphorbiaceae). These measures were compared against rates of evolution and patterns of divergence among 24 populations in two species in the D. scandens species complex. We found clear ...[more]

PMID: 25002700

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Genetic constraints predict evolutionary divergence in Dalechampia blossoms.

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Genetic constraints predict evolutionary divergence in Dalechampia blossoms.

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