Premium
The Control of Sea Urchin Metamorphosis: Ionic Effects
Author(s) -
Cameron R. Andrew,
Tosteson Thomas R.,
Hensley Valentine
Publication year - 1989
Publication title -
development, growth and differentiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.864
H-Index - 66
eISSN - 1440-169X
pISSN - 0012-1592
DOI - 10.1111/j.1440-169x.1989.00589.x
Subject(s) - metamorphosis , sea urchin , fishery , oceanography , chemistry , zoology , biology , ecology , geology , larva
Because the cascade of events which comprise sea urchin metamorphosis occur rapidly, regulatory mechanisms able to respond in minutes must function. Employing sea water solutions of altered ionic composition in the presence or absence of metamorphically active microbial films, we tested the ability of particular ions to inhibit or enhance metamorphosis in competent larvae of the sea urchin, Lytechinus variegatus . At 40 mM excess potassium maximally induces normal metamorphosis in the absence of a microbial film. In the presence of metamorphically active microbial films, 40 mM excess magnesium inhibits the process. Increasing concentrations of calcium up to an excess of 40 mM stimulates larvae to undergo metamorphosis but in smaller proportions than similar concentrations of potassium. Divalent cation‐free sea water solutions are toxic to larvae. These studies support the hypothesis that ion fluxes are involved in the regulation of metamorphosis and reveal a complexity of response that parallels the histological complexity of competent echinoid larvae.