What This Clam Does WON'T Shock You!

I just got back from a week-long diving trip to the Philippines. While there, I encountered something I’d never seen before – a species of saltwater clam called Ctenoides ales – commonly referred to as an “Electric Clam” or “Disco Clam.”  Flashes of what appear to be blue-white electricity course through the creature, sort of what you might see in an electric eel.

Turns out, though, it ain’t electricity that’s doing the flashing.  According to Lindsey Dougherty, a researcher from the University of California Berkeley, it turns out that the lights are not from bioluminescence, but instead are only from reflection of sunlight in the ocean (or, in my case, a couple of 1200-lumen underwater flashlights I use when taking photos and videos). The clams have a highly reflective tissue on the very outer edge of their mantle that is exposed and then hidden very quickly, so the change back and forth from the white reflective tissue to the red tissue creates the appearance of flashing.

So the next time you encounter one of these incredible creatures, go ahead. Stick your finger in it.  Then tell me what happens.