Projeto de pesquisa

The common tropical barnacle Chthamalus bisinuatus and the mottled shore crab Pachygrapsus transversus are two broadcast-spawning marine crustaceans naturally distributed along most of the South American Atlantic coast. Although both species share similar distribution patterns, they differ greatly in the amount of time spent developing in the water column as planktonic larvae. Such contrasted life-histories are likely to play an important role in the extent at which larvae are exchanged between populations. Since gene flow between populations occurs mainly through larval dispersal, studies evaluating the genetic structure and connectivity of populations at different temporal and spatial scales would provide useful information as to whether larval duration is a good proxy to predict high dispersal. This project will be separated into three major components: (1) isolation, primer design and characterization of highly polymorphic microsatellite markers for the common tropical barnacle C. bisinuatus and the shore crab P. transversus; (2) genetic population structure of C. bisinuatus and P. transversus across their natural distribution; and (3) temporal monitoring of C. bisinuatus larval cohorts from birth to settlement using genetic parental analyses to assess the overall importance of larval retention in recruitment processes. This study will be important for the ecology of broadcast-spawning marine invertebrates as it will increase our understanding of larval dispersal processes and their effects on the genetic population structure at different spatial and temporal scales.