Chlorophyll a in some Corals and Marine Plants

Abstract

ASSOCIATIONS of algae and marine invertebrates are common in coral reefs of tropical seas. According to Yonge^1,2 the algal components of corals obtain carbon dioxide and nutrients from the associated animals; but just what advantages of pseudosymbiosis accrue for the individual animal body has not been clearly demonstrated. Odum and Odum³ have expressed the view that the algal-coelenterate complex of tropical coral reefs is “a highly integrated ecological unit (comparable to the algal-fungal complex of a lichen) which permits cyclic use and re-use of food and nutrients necessary for vigorous coral growth in tropical ‘desert’ waters having a very low plankton content”. New approaches to this problem of symbiosis have been developed recently by the growing of single-celled zooxanthellæ isolated in pure cultures from marine jelly fish and sea anemones, and demonstration that these are in reality motile dinoflagellates⁴. It has not been clearly shown whether these photosynthetic flagellates contribute food supplies to the animal polyps.