Wednesday, December 7, 2011

Studying Gastropods – Unweaving all those winds and spirals

By Chong CHEN, PhD Student, University of Oxford

Have you ever wandered across a beach or shore, picking up seashells for admiration as you went? Well, that’s how my interests in Mollusca, the second largest phylum of the entire animal kingdom (containing seashells, octopuses, squids, etc.), began. Although I am interested in all groups within Mollusca, my primary interest lies in the class Gastropoda (coiled univalves or “snails”).
The more I learnt about gastropods, the more I am intrigued by them. At first, it was the amazing shapes of Sthenorytis pernobilis (noble wentletrap) and the fantastic patterns / colours of Conus gloriamaris (glory-of-the-sea cone). Then, it was the great diversity of ecological roles and adaptations shown by gastropods – some examples are the parasitic ovulids living under coral polyps, the tremendous dispersal ability of the wandering triton, Ranella olearium, and the iron-plated armour of the scaly-foot gastropod. My unstoppable fascination for gastropods led me to start an academic career to find out more about them, and to this expedition.
Gastropods are often an important group in deep-sea ecosystems, such as the extremely widespread predators Buccinus sp. and Fusitriton sp.; and various types of snails (e.g., Alviniconcha sp.) found in very high densities in hydrothermal vents. It is truly exciting to find out what roles they play on the Southwest Indian Ridge.
Through this expedition, I am hoping to find answers to some questions I have in mind regarding gastropods (and molluscs general) in these seamounts, such as: What species are living on these seamounts? Are they endemic (specific to that region of the world)? What factors influence their distribution? What habitats do different species prefer? How are the populations on different seamounts linked? …. And many others!
I have seen some motivating hints to answering these questions in the past month, and the hydrothermal vents expedition has also been more than enthralling. I hope the rest of this cruise continues to be exciting and thrilling, and I am already looking forward to work on the materials collected when I get back to Oxford!

Fusitriton magellanicus (Ranellidae),
a widespread carnivorous species.
Otukaia sp. (Calliostomatidae), a grazer,
probably associated with live corals.