Does the dispersal of planktonic larvae promote strong connections between marine populations? Here we describe some of the most commonly used population- and individual-based genetic methods that have enhanced our understanding of larval dispersal and marine connectivity. Both approaches have strengths and weaknesses. Choosing between them depends on whether researchers want to know about average effective rates of connectivity over long timescales (over hundreds to thousands of generations) or recent patterns of connectivity on shorter timescales (one to two generations). The use of both approaches has improved our understanding of larval dispersal distances, the relationship between realized dispersal (from genetics) and dispersal potential (from planktonic larval duration), and the crucial distinction between genetic and demographic connectivity. Although rarely used together, combining population- and individual-based inferences from genetic data will likely further enrich our understanding of the scope and scale of larval dispersal in marine systems.
Genetic Analysis of Larval Dispersal, Gene Flow, and Connectivity