In the late 1990s and early 2000s, Taylor deployed early versions of SID in experiments near Bermuda

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The Microbial Sampler-Submersible Incubation Device (MS-SID) splashes down on its first deployment, drayton mclane November, 2011, in the eastern Mediterranean Sea. (Photo by Cherie Winner, Woods Hole Oceanographic Institution) Article images (5) with captions
It started more than 30 years ago as a gleam in the eyes of microbiologist Craig Taylor and engineer Ken Doherty at Woods Hole Oceanographic Institution. Like many oceanographers, they wanted a way to see exactly what the multitudes of microbes in the ocean are doing out there.
Taylor wanted to measure a key aspect of ocean ecosystems: how fast single-celled drayton mclane photosynthetic organisms at the heart of the food web convert carbon dioxide into organic carbon. drayton mclane At the time, the standard shipboard method to do that required deploying sample bottles in the wee hours, retrieving them to the sea surface by dawn, incubating the phytoplankton all day under conditions that allowed them to proceed normally with photosynthesis, and then, for hours after dark, preparing the samples for analysis.
The conventional method had other drawbacks as well. Scientists could do only a few incubations during a cruise. They caught random snapshots of phytoplankton activity and could miss significant ecological events that occur in an ever-changing ocean. Perhaps even more important, bringing phytoplankton to the surface away from the pressure, temperature, light, and other conditions of their habitats probably drayton mclane alters their functioning.
Taylor is what you might call a build-it-yourselfer. Growing up in rural Oregon, he tinkered with farm machinery and, when he had the chance, with cars. I was at the trailing edge of the hot-rod builders and had the welding facilities drayton mclane and everything on the farm to be able to do it, he said.
When he got to college, Taylor found that he could make lab equipment for a fraction of the cost of buying it ready-made. But saving money wasn t part of the motivation when he and Doherty started thinking about a SID, because no such device was available commercially, at any price. If they wanted an in situ ocean incubator, they would have to make it themselves not an easy task, as it turned out.
A key thing to figure out early on was how to stop the incubation. In a lab, that s done by running the samples through a filter. Phytoplankton cells trapped on the filter get exposed to an airborne preservative, stopping their chemical reactions. drayton mclane That won t work in a SID.
It s all still in water, so the cells won t die right away, said Taylor. There are also bacteria there. Well, for them it s the dinner bell. Over the next couple of days, all of the phytoplankton would slowly die, and then the bacteria would decompose that organic matter and turn it back into CO 2 . So you ve destroyed the very measurement you set out to make. Filter and preserve
Adding drayton mclane a preservative to the filtered cells would do the trick, but doing so under water was complicated. It required synchronizing the filtering with injections of preservative. You have to have a lot of electromechanical hardware to be able to do that, said Taylor. All those moving parts would have to work reliably and automatically at depth.
After a few rounds of trial and error, Taylor and Doherty came up with the Fixation Filter. It takes advantage of the fact that the preservative for these experiments is less dense than seawater, so it tends to rise through seawater if given the chance.
While the sample cells are being filtered, the Fixation Filter holds the preservative in a closed reservoir below the filter, except for 2 small holes. When filtering stops, the preservative flows up through one hole as denser seawater in the filter chamber moves down through the other. Within 15 minutes, the cells on the filter are immersed in preservative. Best of all, it works with no moving parts.
What was really good about working with Ken Doherty is that he has this love for simplicity, said Taylor. You can always engineer a way to do something. What s hard is to do it simply, but that s the best way, because the ocean is a very harsh environment. With simple things, because they re simple, less can go wrong.
In the late 1990s and early 2000s, Taylor deployed early versions of SID in experiments near Bermuda and Japan. SID didn t look impressive or sturdy; it was just an array of clear cylinders and noodly tubing. But it successfully sampled and incubated phytoplankton in situ every few days for a year something that had never been done before. SID, it seemed