SLURPING OYSTERS from their shells could also be a uncommon indulgence for people, however these bivalve molluscs and their relations, comparable to clams and mussels, slurp for a residing. Most are filter feeders, ingesting microscopic organisms in addition to particles from their aquatic environments. A handful of mollusc species, nevertheless, have shaped symbiotic partnerships with algae that reside inside their tissues. These people increase their food regimen with sugars that their microscopic companions produce by means of photosynthesis.