Those Ravishing Rudists Trivia Quiz

Answer: Ice cream cone

Rudists, like all bivalves, consist of two valves. Early on, rudists did something to the geometry of their shells to make it so that the valves did not need to grow as coils. So, one valve grew conical and elongated (the ice cream cone), and the other became greatly reduced, and sat on the opening of the other valve like a little cap (the ice cream scoop.) The elongated end sank into the muddy substrate, and over half of the height of the rudist could be submerged in the sediment, something like a modern pen shell.

There are words to describe rudists based on their preferred orientation on the substrate: "Elevators," "Clingers," and "Recumbants."

Answer: Bivalves

I'm not quite sure which group of bivalves rudists are most closely related to. There are several groups of rudists, all with a distinct structure to the shell. Rudists secreted shells made out of calcium carbonate, partly in the form of aragonite, and partly in the form of calcite. Aragonite is relatively unstable, so it is rare to find rudists with the aragonite still preserved.

Answer: Cretaceous

Rudists evolved in the Jurassic. They had their heyday in the Cretaceous, but then went way of the dinosaurs. Rudist reefs tend to be flatter and wider than reefs built by, say, corals. And did you know, rudist experts even debate the accuracy of using the word "reef" to describe rudists? Since you probably don't want to bother with the difference between a reef, a bioherm, a biostrome, and a buildup, I personally am quite content with the word "reef." But if you find yourself at a cocktail party with someone who studies rudists...well, you have been warned.

Answer: Matching wallpaper

Rudists liked the same sorts of environments that corals do: normal marine salinity, almost always the ocean; tropical to temperate regions; and shallow, nutrient-rich water. Different types of rudists liked different sorts of living conditions. You can tell this by watching the number and types of rudist species change across several localities through time. If one type of rudist disappears from one site at one particular time, but not the others, you can guess that something about the environment changed that that species of rudist wasn't too happy with.

Answer: Locomoting

Nope, our action-packed rudists spent their days sitting in the substrate, filter-feeding, secreting carbonates, and reproducing. What a thrilling life.

Answer: No

It seems a few rudists had symbiotic photosynthetic algae, but they were the few, the proud. Filter-feeding provided all the food for most rudists. How do people know this if there are no extant rudists, you might ask? Uh...

Answer: A bouquet

If anyone wants to show up at my house on prom night with a bouquet of rudists, I would be thrilled. I suppose this name came about because some rudists tend to form a sort of bouquet-shaped masses. If you are a fan of Keeping Up Appearances, then I suppose we could have "The Bouquet residence, the rudist of the house speaking!"

Answer: No

Sort of a sad fact. I wonder what a rudist fritter would taste like. No, rudists died out at the end of the Cretaceous, but whether for the same reasons as the dinosaurs is up for debate. Take Jamaica, for instance. The rudists had been living on a shelf constructed by an active volcano.

When big chunks of the shelf broke off and sank into deeper water, it was curtains for the rudists.

Answer: Any of these

Rudists have been found and studied in Spain, Texas, Italy, Turkey, Croatia, Mexico, Jamaica, Greece, the Dominican Republic, Tunisia, Cuba, Iran, Austria, Algeria, Egypt, Oman, and Puerto Rico. Where there be Cretaceous carbonate rocks, there probably be rudists.

Answer: Yes

A surprising number of people study rudists-- somewhere between fifty and a hundred, perhaps? International Rudist Conventions are held every three years, located in the past in such lovely places as Croatia, Texas, and Australia. The 2008 meeting will be held in Turkey.

There seems to be a tradition that after a day of talks, everyone goes out to dinner together, and after the food and the wine, everyone sits around and SINGS. Nothing beats a bouquet of rudistophiles doing their rendition of "O Sole Mio"!