Freak Week: Creepy Clams
Posted On: 10/29/2017 - 9:14am, Posted By: Other
This post guest-authored by Dee Broomhead, current Zoology Intern and student at NKU.
Welcome back to Freak Week! I’m your host for this eerie expedition, Ichabod Bones. This time, we look at a monster of the depths, the Giant Clam (Tridacna gigas). This massive creature is the subject of many legends in South Pacific cultures. One such myth, from Melanesia, chronicles a hero’s near-death encounter with this deep sea giant. Our champion, Lata, is warned by his mother to avoid the clam, but while voyaging in his canoe, he finds himself being drawn in by a strong current towards the clam’s enormous “jaws”! Lata valiantly thrusts a log upright into the clam and swims away to safety.
While the tale of Lata and his run-in with a dangerous clam is merely folklore, some divers today fear being caught in the clam’s grasp. However, there is no need to fear! The adductor muscles of the clam, which allow it to open and close its two shell pieces (the “valves”), move too slowly for the clam to be able to slam closed on a passing diver with enough speed to catch them. Besides, these gigantic beings would much rather withdraw into their shells to hide from a human passerby than attempt to take a “bite.” This clam doesn’t even need to seek out much food; a kind of symbiotic, photosynthetic algae lives within its tissues, feeding the clam in exchange for a place to live. If the algae isn’t enough, the giant clam will filter plankton out of the surrounding water to sustain itself.
For you to get an idea of the sheer size of this specimen, here it is pictured next to an elephant skull! This creepy clam can grow to be over 440 pounds and frequently lives to be older than 100 years. You may be wondering how something this large can move around. Well, it can’t! When the giant clam settles somewhere, it attaches to that spot for life. Though people often consider this behemoth to be a threat to humans, quite the opposite is true. The clam’s adductor muscle is considered to be a delicacy, and over-fishing has put this species on the “vulnerable” list.
Melanesian Legends found via:
Codrington, R W. “Melanesian Folk-Tales.” South Pacific Tales – Legends and Myths from Tonga, Samoa, Papua New Guinea, Easter Island (Folklore History Series), Read Book Ltd, 2013.