Massive Mellow Molluscs
The giant clams are a tropical subfamily of bivalves specialized to live in warm, nutrient-poor waters on coral reefs. The largest species, Tridacna gigas, grows to nearly 3.5 feet in length and can weigh hundreds of pounds. Contrary to popular belief, they do not shut their shells to trap divers. In fact, these gentle giants are herbivorous! Some of their nutrition comes from filter-feeding on passing phytoplankton, like many bivalves, but the giant clams have attained their unusual size through an unusual symbiotic partnership with algae.