27 February, 2012 RRS James Clark Ross
Adam has joined us from Southampton University where he studies the reproduction and morphology of bivalve molluscs in the Southern Ocean. Like their clam and mussel relatives, Adam’s tiny Antarctic bivalves get their food by filtering seawater. Adam is particularly interested in how the species respond to different environmental conditions such as sediment types, depths and temperatures. In the Southern Ocean, bottom water temperatures are a lot more stable than elsewhere, which means that species here may find it more difficult to adapt to temperature changes… a theory which Adam is keen to test.
To see how well his Southern Ocean bivalves respond to small, regular increases in temperature Adam has to work in the 4°C cold room on the ship, one of the best opportunities to study his animals alive as they are hard to maintain in captivity. At the bottom of the Southern Ocean they live at around -2°C! By slowly increasing their water temperature and measuring their rates of oxygen consumption he can test their thermal tolerances and in turn determine how the species may respond to rapidly changing environmental conditions. In this way he can learn about their capacity to adapt, which is useful for understanding the evolutionary history of bivalves in the Antarctic, and for predicting how these species may cope under potential ocean warming in the future.
So far he has been able to test one shallow water filter feeder species and two deeper water deposit feeder species. He is really hoping to catch more of the deeper water species in the next few days to make the most of this opportunity.