Dearest Anais,

Anja

ALVIN returns from its first dive

Tonight things were a bit slow, at least for me. We are now at a stage in our cruise where every day we launch ALVIN, the small submersible that carries three people--a pilot and two scientists. The main purpose of these particular dives is to collect information on and samples of the critters that live near the hydrothermal vents. As you probably know all too well, I study rocks, not critters, and thus, am not involved with this research. We shall return to the mapping in a few days. Standing around with my hands in my pocket but trying to look intelligent, I figured I should probably do something useful and volunteered to help the biologists with the stuff they brought up with ALVIN. So I extracted tube worms from tube worm tubes for them. Now tube worms are really weird creatures. (I imagine that the tube worms are thinking the same thing about us, but that is a different matter.) And I will admit to not knowing anything more about them than you do, at least not before I started extracting them from their happy homes, and so now I shall tell you everything I do know, which as you can see is not much.

Tubeworms

First of all, tube worms make for themselves a home of a hollow tube, like a straw, which can be anywhere from a few inches to a few feet long, depending on the neighborhood, and there they spend their entire lives. The weirdest thing about them, however, is that they don't actually eat anything. It might seem obvious that if you don't eat you don't need a stomach, or for that matter a mouth or anything between your mouth and your stomach and your stomach and your rear end. And, in fact, none of those things do tube worms have. If tube worms dont eat, don't they get hungry? No, because they have mastered a culinary art unknown to you and I--they get someone to eat for them. (I know what you're thinking--you're wondering if you could get someone to eat your spinach for you.

Tubeworm bush

Don't get your hopes up.) The lucky devils to assume the role of the gourmet are tiny little beasties called bacteria, which live as a community inside the tube worm. What the tube worm does is to take chemicals out of the water and provide it to the bacteria. The bacteria eat these chemicals, and turn the chemicals into food for the tube worm. Et voila, dinner! Oh, but there is just one added complication, namely that the chemicals that the bacteria eat and turn into food for the tube worm come out with the hot water from the hydrothermal vents, and these chemicals are not generally in the surrounding seawater. So if water stops coming out of the vent and you happen to be a tube worm...why, you are toast!

So, that is the story of tube worms. Goodnight kiddo.

Love, Papa