Common garden experiments to study local adaptation need to account for population structure

Pierre de Villemereuil (1) , Oscar Gaggiotti (2) , Jérôme Goudet (3)

1 ISYEB - Institut de Systématique, Evolution, Biodiversité
2 SOI - Scottish Oceans Institute [University of St Andrews]
3 UNIL - Université de Lausanne = University of Lausanne

Common garden experiments are valuable to study adaptive phenomenon and adaptive potential, in that they allow to study local adaptation without the confounding effect of phenotypic plasticity. The Q ST − F ST comparison framework, comparing genetic differentiation at the phe-notypic and molecular level, is the usual way to test and measure whether local adaptation influences phenotypic divergence between populations. Here, we highlight that the assumptions behind the expected equality Q ST = F ST under neutrality correspond to a very simple model of population genetics. While the equality might, on average, be robust to violation of such assumptions , more complex population structure can generate strong evolutionary noise. Synthesis We highlight recent methodological developments aimed at overcoming this issue and at providing a more general framework to detect local adaptation, using less restrictive assumptions. We invite empiricists to look into these methods and theorists to continue developing even more general methods.

Mots clés: Local adaptation; common garden; Q ST − F ST comparison; population structure; phenotypic divergence; population genetics; quantitative genetics

Domaines: Evolution [q-bio.PE]; Génétique des populations [q-bio.PE]

Pierre de Villemereuil, Oscar Gaggiotti, Jérôme Goudet. Common garden experiments to study local adaptation need to account for population structure. Journal of Ecology, 2022, ⟨10.1111/1365-2745.13528⟩. ⟨hal-02976905⟩