Episode 107: Disco Clam: Saturday Night Survivor

“…and today we’re returning to an old friend, but we’re going to hear the other side of the story.”

Today we’re returning to familiar territory. We’ve covered a brilliant and formidable predator that seems to be unstoppable because of its powerful punch. But there’s at least one item on its menu that’s not going into the ring unprepared. But when you’re going up against the tidal Tyson, you’re probably not going to win in a slug-fest. Instead, this clever clam turns to a brilliant tactic to outsmart the killer crustacean. But sometimes it pays to be bright in Life, Death, and Taxonomy!


  • Basically looks like a pair of voluptuous and horrifying red lips
  • Well, it’s kind of a bright orange-red.
  • And there are dozens of tentacles coming out of the lips, which 
  • The entire kit and kaboodle is housed in a regular-looking clam shell, which it can retreat into if it’s threatened.

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words measure up into ldtaxonomy at gmail dot com. We have a new measure up intro from Abi and Joel (and Bibby). This one was also procured by Carlos, who’s this person?


  • According to exotic aquarium websites they are between 1” and 2.5”
  • 2 inches.
  • How many disco clams go into the diameter of the world’s largest disco ball?
  • Hint: The ball was created for the four-day UK music festival called Bestival in 2014.
  • Answer: 203 clams. The ball was 10.33 m (33’10”) in diameter.

Life Span

  • 27 to 30 years.
  • 30 years.
  • How many Disco Clam life spans go into the amount of time between now and the first number one song on the American Disco charts?
  • Hint: The first ever number one disco song was Gloria Gaynor’s Never Say Goodbye.
  • Answer: 1.5 disco clams. The song made the charts in 1974, which is 46 years ago.

Fast facts

  • I think this is the first bivalve we’ve done on this show, so let’s talk a bit about clams.
  • Bivalves are molluscs that have laterally compressed bodies all wrapped up snug and tight in a shell.
    • The shell is made up of two sides (or valves) made of calcium carbonite that are connected by a hinge held together by several teeth and a flexible ligament
  • These include oysters, scallops, mussels, and—you guessed it—clams.
  • They don’t have heads or brains, but they do have 40 simple eyes to detect lights and shadows. 
  • They also have that certain sulfuric touch that I think is lacking in today’s modern bivalve. Always too afraid to offend, never brave enough to douse their enemies in acid. It’s sad, really.
  • But seriously, they got footage of the venerable heavyweight mantis shrimp trying to make an easy meal out of Tony (and, with a punching force of a 22 calibur bullet, that shell isn’t doing much work).
    • But the mantis shrimp pulled back in pain and disgust when it touched Tony’s toxic feelers, so don’t mess with the best.
  • Tony, like other members of the order Limidae, is likely able to swim using a combination of flapping its shell and using its tentacles. Though it spends most of its time nestled in a rock cranny… or nook, whichever you like.
  • Despite the fierce weaponry at his disposal, Tony’s a leaf-eater. More specifically, he only eats phytoplankton that he filters through his weird orange clown lips.

Major Fact: Disco fever

  • One of the disco clam’s main predators is the infamous mantis shrimp.
  • The first defense for a clam is usually to close up tight and wait for predators to pass. 
  • It’s usually enough, but the mantis shrimp has a powerful punch that can break right through a clam’s calcium carbonate defenses.
  • However, when the mantis shrimp approaches the disco clam, it breaks the first rule of being a clam. It opens.
  • The disco clam gets its name for its ability to produce a bright flashing display along the edge of it’s mental. 
  • The mantle is inside the shell. When they mantis shrimp approaches, the clam opens up and begins it’s brilliant display.  
  • Mantis shrimp have been observed stopping its attack and going into a catatonic state for up to 15 minutes.
  • Lindsey Dougherty is a prominent disco clam researcher and that has explored the way the clam makes light.
  • Research in the 90s found that clam’s light display doesn’t work in the same way other light producing sea creatures do. 
  • It’s not bioluminescence, which is a chemical reaction that produces light. 
  • Instead, it’s a sophisticated reflector system called silica nanospheres, which she compares to tiny disco balls. 
  • Dougherty found that their mantels are made of two different types of tissues. The silica lip reflects light while the other side of the mantle absorbs light, making the silica appear brighter. 
  • This allows the clam to reflect ambient light. 
  • It’s less useful at night or the pitch dark. However, it’s much brighter during the day than bioluminescence.
  • Researchers are looking at how they use this ability.
  • It seems clear that they use it to ward off predators. In lab tests, when started by fake predators, the clams reflective flashing became more rapid.
  • Mantis shrimp are very bothered by the flashing and in addition to the stupor it puts them in, they’ve also been seen cleaning their mouth parts in response.
  • The clams have also been observed flashing faster when given food, so they may also use this ability to attract prey.
  • They cannot see their own flashing, so it’s not meant to communicate with each other.


Hey, LDT listeners! Do you have animal suggestions for our next episode. We usually try to find a place to put suggested interesting animals on our list. If you know of a creature with some interesting ability, let us know by emailing LDtaxonomy at gmail dot com or connecting with us on Twitter or Facebook at LDtaxonomy. That’s for listening and engaging!