Beside collecting slitsnails, water and sediment are sampled at various depths. To collect water, Dr. Gillevet deploys a butterfly niskin, a device that opens, fills, and then seals a plastic bag. Back in the lab, liters of clear seawater are pumped through microfilters. About all you can see after filtration is a slight yellow tinge on the filter paper, and that is exactly what he's looking for--microorganisms--especially bacteria. Pat is studying the characteristics of ocean microorganisms and their possible interactions in marine ecosystems. As with all the organisms collected, getting them on board the ship is only the first step. The next step is to isolate and extract genetic material as a way to fingerprint them.

DNA is also extracted from the gastropods we collect. Slitsnails are like living dinosaurs, and they provide a window into the past. How is it that these animals have survived for hundreds of millions of years with little significant physical change? If they have changed over time, in what ways, and how similar and different are they from other living gastropods? These are some of the questions that can be approached by sequencing slitsnail DNA. Being able to extract DNA on board the ship shows just how far the field has progressed. Our scientists set up their own equipment in the dry lab, the key pieces being a blender, vortex, centrifuge, incubator, and microscope. The DNA being studied comes from mitochondria, organelles that function in cellular respiration. Basically, mitochondria are involved in converting food to a useable form of chemical energy. The DNA that controls our growth and development, and just about everything else, is located in the cell nucleus. Mitochondrial (mt) DNA is within the mitochondria which are outside the nucleus, a fact that along with other evidence suggests the ancestors of mitochondria were bacteria. One thing that makes mtDNA profitable to study is its small size, approximately 16,500 units (base pairs).

Tissues rich in mitochondria must be used if enough DNA is to be collected. On a snail, one obvious source is muscle tissue. With large snails, we have the luxury of avoiding tough foot muscle, and instead dissect out heart muscle and gonads which are rich in DNA for obvious reasons. At left, Jerry demonstrates just how a vice is used to separate the soft tissue from the hard shell. A hand held blender breaks down the tissue and breaks open the cells. The cellular contents, including the mitochondria, are spun in a centrifuge at high speed to separate the cellular components into layers according to the mass of the parts. After several steps, a pellet of mitochondria is isolated and detergents are applied to separate the mtDNA. Eventually, everything works and a small pellet of mtDNA is obtained from each samples. The mtDNA samples will be analyzed, amplified, and sequenced at the National Museum of Natural History, and at George Mason University. These sequences will eventually be compared to similar sequences from other groups of gastropods. What emerges are patterns of relationship between groups, the genealogy, and a picture of the evolutionary history of this large group of animals.

Sometime in the evening the crew takes a break from the work. Ice cream always seems to to restore humor.