Biogeographic filters of function and phylogeny determine morphological disparity with latitude
Project
ID: 00000C692
Public
Using high-resolution 3D CT scans to compare the shell morphology in marine bivalve faunas of tropical Florida Keys and boreal Gulf of Maine, we find that regional morphological shifts between whole faunas and in subgroups of faunas conform to hypothesized effects of resource seasonality (Valentine 1971, Pigot et al. 2015) and predation intensity (Vermeij 1978, 1987), albeit with a change in total variance rather than a simple directional shift, but not to predicted effects of carbonate saturation/calcification costs (Watson et al 2012). Loss of functional groups and family-level clades at high latitudes, rather than latitudinal shifts in morphology within widespread functions and families, largely drives the faunal contrast. Latitudinal differences in morphology thus represent a complex integration of phylogenetic and ecological factors that can only be captured in multivariate analyses.
DESCRIPTION
Using high-resolution 3D CT scans to compare the shell morphology in marine bivalve faunas of tropical Florida Keys and boreal Gulf of Maine, we find that regional morphological shifts between whole faunas and in subgroups of faunas conform to hypothesized effects of resource seasonality (Valentine 1971, Pigot et al. 2015) and predation intensity (Vermeij 1978, 1987), albeit with a change in total variance rather than a simple directional shift, but not to predicted effects of carbonate saturation/calcification costs (Watson et al 2012). Loss of functional groups and family-level clades at high latitudes, rather than latitudinal shifts in morphology within widespread functions and families, largely drives the faunal contrast. Latitudinal differences in morphology thus represent a complex integration of phylogenetic and ecological factors that can only be captured in multivariate analyses.