Endosymbiosis: From Sunlight to Seafood

Our beautiful new 222-page ebook, SAVING GIANTS: Cultivation and Conservation of Tridacnid Clams (by Gerald Heslinga, 2013) is now available for download [or go to and search for SAVING GIANTS] References: Adult giant clams harbor enormous numbers of symbiotic unicellular dinoflagellates called zooxanthellae. These algal symbionts function as internal solar collectors, converting sunlight, carbon dioxide and dissolved nutrients into carbon-based photosynthates including glucose, amino acids and other substances, some of which are released directly into the bloodstream of the host clam. This symbiotic relationship provides most or all of the nutritional needs of the host clams, and allows them to grow faster and larger than conventional filter-feeding bivalve molluscs even in the plankton-poor waters of coral reefs. The sym