The shell to the right with a hole through it was hinged to another shell of equal size with an animal living inside (in this case, a clam). Animals with two shells hinged together are known as bivalves. Often, in restaurants oysters and clams are shucked and served “on-the-half-shell” (Yum! I prefer them plain, but sometimes mix it up with ones with plenty of horseradish!).
Animals in the ocean do not have the luxury of someone shucking their prey, but rather use an adaptation called a radula. A radula is the sharp, drill-like tongue of some mollusks (e.g., whelk or conch). Radulas are found on every class of mollusk except for bivalves. A whelk or a conch would use their radula to drill into the clam and then slurp out its meal … Leaving behind a perfectly symmetrical hole. Moon snails and oyster drills are also well-known for using this technique to drill into clams for a feast.
Image (c) imageshack.us
The Other 95% has a video clip of an Oyster Drill using it’s radula and accessory boring organ to drill through an oyster similarly to a moon snail drilling through a clam. Even cooler is the sound of the radula… though for the oyster it must be akin to fingernails on a chalkboard.
]jwh251
]Biohazard Cleanup San Diego
Great Post! I am linking to it from my blog this Monday morning.Your post will perfectly explain why some of my seashells have a perfect hole in them. Kathy