DOI: 10.5061/dryad.28b06
title: Data from: High evolutionary constraints limited adaptive responses to past climate changes in toad skulls

description: Interactions among traits that build a complex structure may be
 represented as genetic covariation and correlation. Genetic correlations
 may act as constraints, deflecting the evolutionary response from the
 direction of natural selection. We investigated the relative importance of
 drift, selection, and constraints in driving skull divergence in a group
 of related toad species. The distributional range of these species
 encompasses very distinct habitats with important climatic differences and
 the species are primarily distinguished by differences in their skulls.
 Some parts of the toad skull, such as the snout, may have functional
 relevance in reproductive ecology, detecting water cues. Thus, we
 hypothesized that the species skull divergence was driven by natural
 selection associated with climatic variation. However, given that all
 species present high correlations among skull traits, our second
 prediction was of high constraints deflecting the response to selection.
 We first extracted the main morphological direction that is expected to be
 subjected to selection by using within- and between-species covariance
 matrices. We then used evolutionary regressions to investigate whether
 divergence along this direction is explained by climatic variation between
 species. We also used quantitative genetics models to test for a role of
 random drift versus natural selection in skull divergence and to
 reconstruct selection gradients along species phylogeny. Climatic
 variables explained high proportions of between-species variation in the
 most selected axis. However, most evolutionary responses were not in the
 direction of selection, but aligned with the direction of allometric size,
 the dimension of highest phenotypic variance in the ancestral population.
 We conclude that toad species have responded to selection related to
 climate in their skulls, yet high evolutionary constraints dominated
 species divergence and may limit species responses to future climate
 change.
description: Species means and
 residual P-matricesThe data are species
 climatic means (bio1 through bio19 extracted from WorldClim database for
 all localities the species are reported to occur. For variable definitions
 see: http://www.worldclim.org/bioclim. Further information in Hijmans et
 al. (2005) Int. J. Climatol. 25, 1965–1978.
 http://dx.doi.org/10.1002/joc.1276. Note bio3 and bio7 were excluded from
 analysis) and morphological means (21 linear skull distances: definitions
 of abbreviations are in the ReadMe file). Next are species residual
 phenotypic variance covariance matrices for which the effects of sex and
 locality were removed (see table S1 of article). The last data is a data
 frame that was used as entry on the function oubm.fit of the slouch R
 package.data_files.csvTable 1. Vector correlations between evolutionary response (Δz), selection (β) and PC1.This is the correct version of Table 1, in which column headings are in the correct positions. Please see the associated README "read_me_table1.txt" for a description of the symbols. Please also see: Correction to ‘High evolutionary constraints limited adaptive responses to past climate changes in toad skulls’ in Proceedings of the Royal Society B at http://dx.doi.org/10.1098/rspb.2016.2354Table 1.pdfread_me_table1.txt