ENVIRONMENTAL-FACTORS INFLUENCING ASEXUAL REPRODUCTIVE PROCESSES IN ECHINODERMS

This review provides a brief update of the occurrence and adaptive sig nificance of asexual reproduction in echinoderms. It then focuses on t he state of knowledge of biotic and abiotic factors that influence ase xual processes in this group, particularly factors that may play a rol e in regulating the expression and relative proportion of asexual vers us sexual phenotypes within populations of species, as well as factors modulating and triggering asexual processes. The information presente d in the review is synthesized into the form of a basic model depictin g how environmental factors may interact with physiological factors to regulate asexual reproduction in echinoderms, and to show how such re gulatory processes may parallel in some ways those known to regulate s exual reproduction. Since the model is based mainly on correlational e vidence derived from comparative field observations, a number of exper imental approaches for testing the predictions of the model are discus sed briefly.