With more than 100,000 species, the phylum Mollusca is extremely diverse and ranges from snails the size of a grain of sand to the giant squid. Living in marine, terrestrial, and freshwater environments, mollusks can be found in nearly every ecosystem on the planet. While not all mollusks have them, these eye-catching shells are a recognizable characteristic shared by much of the phylum. 🐚 [video description] a number of white drawers are pulled open to reveal a wide range of mollusk shells. Th