Meeting Abstract

S3.10  Monday, Jan. 4  It\’s about time: divergence, demography, and the evolution of developmental modes in marine invertebrates HART, M.W.**; MARKO, P.B.; Simon Fraser Univ.; Clemson Univ. mwhart@sfu.ca

Differences in larval developmental mode are predicted to affect ecological and evolutionary processes ranging from gene flow and population bottlenecks to rates of population recovery from anthropogenic disturbance and capacity for local adaptation. The most powerful tests of these predictions use species comparisons to ask how phylogeographic patterns are correlated with larval developmental mode. An important and largely untested assumption of these studies is that species with similar spatial patterns of genetic variation have similar underlying temporal histories of population divergence and gene flow (and that species differences in spatial variation are driven by different historical processes). Teasing apart these temporal and spatial patterns may be important for understanding the causes and consequences of evolutionary changes in larval developmental mode. New analytical methods that use the coalescent history of allelic diversity can reveal the temporal pattern of variation in gene flow, effective population size, and population divergence time. These estimates can be used to identify population histories that are congruent with each other and with predictions based on species differences in larval form, and to distinguish such patterns from examples of dissimilar population histories that underlie similar patterns of spatial variation (phylogeographic pseudocongruence). We briefly review some of these recent analytical developments, and show their potential for refining ideas about the correspondence between the evolution of larval developmental mode, population divergence, and spatial genetic variation.