|Photo by Tim Ryan|
Clams are weird. They're mollusks, and so are related to octopi and snails and even the snails' homeless cousins, the slugs. Most of them find a spot to live and glue themselves down, like plants. Some of them putt around in the water like goofy little bellows. They have a foot and they have teeth but they don't have a head. Basically, they're just a loogie in a jewel-box.
So, as you might expect of a headless loogie, they have no brain. They do have a nerve network of sorts that allows them to react appropriately to things, but without having to get all philosophical about it. There's really not a lot to a clam, so some of their bits do double duty. For instance, their hearts and kidneys also figure in the reproductive system, and their digestive tract is responsible for writing commemorative poetry for special occasions.
Your giant clam is planning to bulk up to five hundred pounds. He is able to snag a snack here and there as it drifts by, but mostly he's operating a feudal system, luring in algae under the pretense of providing protection, and then letting them do all the farming and paying a massive tribute.
There is a clam that allows a bit of itself to protrude from its shell and take the
and form cysts. Then the baby clams eat up everything inside their cysts until they're big enough to bust out and leave, and the fish is apparently none the worse for it all, although one would think it might feel itchy, or nervous.
None of this applies to the giant clam, however, which is well anchored, living off the profits of its tenant algae's labors, and dreaming of Lloyd Bridges. Lloyd Bridges is famous for a television show called Sea Hunt in which, week after week, he was required to go underwater with just enough air for one fewer person than he encounters. On a good week he gets snapped into a giant clam. You can't blame the clam. Lloyd Bridges was a lot more delectable early in his career than he was when he picked the wrong week to quit sniffing glue.
Scientists claim that no deaths by giant clam have every been substantiated, although there is a huge roster of people who have been "lost at sea," so I'm not sure how they can be so certain. Their notion is that a giant clam cannot actually snap shut. Some of them can't shut all the way and none of them close up very fast, so one would have to be very preoccupied indeed not to notice an encroachment.
But "preoccupied" is the least you can say about people who are engaged in stroking the velvety lips of a giant clam.