We all hope to be interesting people in our lives, but for the boring giant clam, being able to bore is a power that rocks.
Their dull name comes from an incredible ability of theirs to “bore” themselves into the limestone (dead coral) rock by secreting acid at the base of their shell – dissolving rock below them, while they wiggle themselves into a custom-fit bunker of their own making.
Photo credit: Karishma Goenka
If you find yourself exploring the shallow rocky and sandy shore of the Andaman Islands, you might notice brightly coloured iridescent slits opening and closing on the limestone rock that you walk on. These are the boring clams, and they range from electric blue to deep purple in colour in the Andamans.
These clams primarily feed on sunlight through their symbiotic relationship with tiny marine algae called zooxanthellae, that are present on a magnificently coloured mantle (which is the thin fleshy layer at the opening of the shell).
On closer inspection of the mantle you will notice starry constellations of brightly coloured spots. These are called “iridocytes” and they act as specialized prisms to filter out the most delicious colours of light for their symbiotic algae to use.