POPULATION GENETIC-STRUCTURE IN BROODING SEA-ANEMONES (EPIACTIS SPP) WITH CONTRASTING REPRODUCTIVE MODES

Effects of dispersal and mating systems on the genetic structure of po pulations were evaluated by comparing five sea anemones: four Epiactis species that brood their offspring to the juvenile stage and one Anth opleura species that broadcasts gametes and has pelagic, planktotrophi c larvae. The anemones were sampled at sites ranging from British Colu mbia to southern California between 1988 and 1992 and were analyzed by enzyme electrophoresis and by multilocus DNA-fingerprinting, Results were only partially consistent with expectations. While all four brood ing species had lower observed heterozygosities than the broadcasting species, not all brooding species had greater population subdivision t han the broadcasting species. The self-fertile E. prolifera had the ex pected evidence of intense local inbreeding (f = 0.955); unexpectedly, the cross-fertile E. lisbethae and E. ritteri also had similar depart ures from random mating (f = 0.957 and 0.831, respectively) probably d ue to biparental inbreeding among near neighbors in small, highly subd ivided populations.