RT Journal Article
SR Electronic
T1 Dimensionality and modularity of adaptive variation: Divergence in threespine stickleback from diverse environments
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.10.31.466679
DO 10.1101/2021.10.31.466679
A1 Grant E. Haines
A1 Louis Moisan
A1 Alison M. Derry
A1 Andrew P. Hendry
YR 2021
UL http://biorxiv.org/content/early/2021/10/31/2021.10.31.466679.abstract
AB In nature, populations are subjected to a wide variety of environmental conditions that affect fitness and induce adaptive or plastic responses in traits, resulting in phenotypic divergence between populations. The dimensionality of that divergence, however, remains contentious. At the extremes, some contend that populations diverge along a single axis of trait covariance with greatest availability of heritable variation, even if this does not lead a population directly to its fitness optimum. Those at the other extreme argue that selection can push populations towards their fitness optima along multiple phenotype axes simultaneously, resulting in divergence in numerous dimensions. Here, we address this debate using populations of threespine stickleback (Gasterosteus aculeatus) in the Cook Inlet region of southern Alaska from lakes with contrasting ecological conditions. We calculated effective dimensionality of divergence in several trait suites (defensive, swimming, and trophic) thought to be under correlated selection pressures, as well as across all traits. We also tested for integration among the trait suites and between each trait suite and the environment. We found that populations in the Cook Inlet radiation exhibit dimensionality of phenotype high enough to preclude a single axis of divergence.Competing Interest StatementThe authors have declared no competing interest.