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Andrea Skloss's picture

Marine Worms....

On Dr Ken Dunton's team (University of Texas Marine Science Institute) is Susan Schonberg, a benthic taxonomist. Last year in the region of Hanna Shoal, she found some polychaetes (marine worms) that are potentially new species to science. The significance of her discovery was that these worms had been seen many times before, but apparently had been mis-identified. And you thought everything had been identified in and around the United States.... well think again. Polychaetes are my favorite worms.... they come in different shapes, sizes, and colors. The science going on aboard this ship is exciting.

Fat wormWhat is this fat worm? Find out in the next journal.

more wormsLook what we found in the mud!

double Van Veen gabThis is a double Van Veen gab used to collect mud.

sorting tableThe sorting table is used for removing organisms from the mud.

Susan at the microscopeSusan identifying marine invertebrates.

Clams are not just for eating....

Jordann and clamsJordann sorting clams

clamsJordann's clams

Jordann Young is starting her second year of graduate study working on her masters under the supervision of Susan and Ken. She is helping Susan with the benthic infaunal samples, but is particularly interested in bivalves (clams). Her clam project is two-fold. First, she wants to know how clams fit into arctic food webs (the trophic level or position an organism occupies in a food chain) and identify their carbon (or food source). Second, she is interested how their population structure or demography changes on both spatial and time scales. She believes she can age her clams by looking for growth rings (a field called sclerochronology).

Nitrogen has a heavy stable isotope (N15) that bioaccumulates in animal tissues as a function of its trophic position. The more N15 in an organism, the higher its trophic position in the food pyramid. There is a heavy isotope of carbon (C13) that can help identify its ultimate food source. The C13 isotope of carbon does not bioaccumulate very quickly. Her growth ring project not only can tell us the age of the clam, but something about the regional climate. (We can do the same type of analysis on tree rings.) Sclerochronology is not exclusive to clams; it can be used for corals and otoliths (fish bones located in the inner ear). When you compare tree rings to growth rings of other organisms, this cross dating technique can help you determine the age of the organism. Jordann told me that this approach has yielded estimate of clams that are up to 500 years old! I hope we find one!