Biochemical Genetic Variation, Growth and Regeneration of the Sea Anemone,Metridium, of British Shores

Abstract

Sessile organisms capable of asexual reproduction may be expected to show much genetic differentiation among local populations: mating between distant individuals is unlikely and genetic drift will contribute to differentiation since habitats can be colonized by one or a few individuals. This study investigates genetic differentiation of populations of the sea anemoneMetridium senile(L.) in Great Britain. Individuals ofM. senileare sessile and reproduce both sexually, by free-spawning of gametes, and asexually, by regeneration of fragments torn from the pedal disc.Metridium senileis one of the most common and widespread of British sea anemones (Manuel, 1981); reports place it at an enormous number and variety of sites around Britian (unpublished results of surveys by the Underwater Conservation Society of the United Kingdom). The extensive geographic range and variability of the species have confounded attempts to determine the taxonomic status of the ecological and morphological forms, but make it an interesting system for genetic analysis.