ABSTRACT
Competent larvae are induced to metamorphose by sand from a sand dollar bed or an aqueous extract of the sand. Gel-permeation chromatography and high performance liquid chromatography were used to purify a 980 MW peptide that will induce metamorphosis at concentrations of 10-6 - 10-5M. Extracts of whole adults and gonads are also able to induce metamorphosis and adults can condition substrates to induce metamorphosis. It is concluded that the initiation of metamorphosis in Dendraster excentricus is controlled by a pheromone released by adult sand dollars.
