Our professor said: "If you want diversity, they've got it. They're probably one of the most understudied taxa."
(Or words to that effect. I have neither my notes nor time to fetch them.)
What are worms, anyway? The word has even less taxonomic meaning than fish. I can think of six different "worm" phyla without breaking a sweat: hemichordates (acorn worms), nematodes (roundworms), nemerteans (ribbon worms), nematomorphs (horsehair worms), platyhelminths (flatworms, including tapeworms), and acoels (er, other flatworms).
But the worms he was talking about are the ones I could see myself falling for: the Polychaetes. Polychaetes are a subset of Phylum Annelida, which seems to get bigger every time I study it. Right now it includes the earthworms, the leeches, the peanut worms, and the fat innkeeper worms, in addition to my crush.
Polychaetes are just amazing. They've got more flavors than the Friday Harbor ice cream store. There are polychaetes who build tubes out of calcium, out of mucus, out of sand or rocks or shells. They feed with tentacles that look like spaghetti or Christmas trees or anemones, or with horrifyingly sharp jaws. They are all beautiful, often brightly colored and intricately decorated, but some of the most striking are the errant polychaetes. "Errant" is not a taxonomic order, merely a lifestyle choice. These are the polychaetes that keep moving from place to place, too restless to settle down in a tube or burrow. Many are two-dimensional wanderers, keeping to a benthic existence, but many others are swimmers, exploring the whole water column. Swimming polychaetes are incredibly beautiful.
Even polychaetes that don't normally swim often indulge in such behavior at certain times of the year, when moon and pheromones align to stimulate a night of romance. Then, like superheroes in phone booths, they transform themselves from benthic crawlers into elaborate swimmers, and strike out for the surface.
Last night we went nightlighting for these worm alter-egos, called epitokes. We hung a lantern over the water and lay down on the dock, peering into the depths as small fish and crustaceans gathered in the pool of light.
Suddenly a newcomer appeared on the scene: Nereis brandti, a polychaete worm as long as my arm, undulating dramatically along the surface, curving around and around, trailing behind her a cloud of eggs. She seemed almost to be writing in the water, tracing the transient shape of polychaete motherhood. It was a singularly awesome experience--one of those biologic events I wish everyone could see.
(I decided to be slapdash about this post, so I could share the joy of epitoky before it faded from my memory, so I didn't look up any references. I did try to find a video of a nereid epitoke, but no luck. Perhaps it's for the best--a video clip could never capture the experience of sitting in the dark, staring into the sea and seeing nothing but copepods--then out of the black she swims, a veritable Chinese dragon of a worm, spawning deliriously!)