Dive and Discover : Expedition 14 : Mail Buoy, December 6

Read questions and answers in the Mail Buoy

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Ahoy, there! I'm curious to know how you choose the location for your dives and research. Is the crew the same every time? What do you do with your findings? Are they presented to the public in a more simple-to-understand way? And by the way, supposing you eat a lot of fresh fish on board, do you miss home-cooked meals? Thank you very much for your time.
Kyriaki

The location of dives and research depends on the scientific interests of researchers. In this cruise we are interested on organisms that live in the brines where high pressure/salinity and low oxygen conditions prevail. These conditions are present in DHABs of the Mediterranean, that’s why Atlantis left the United States, crossed the Atlantic Ocean and came (for its first time!) just 640 kilometers or 399 miles (considering a straight line) away from Kavala port. You can go to the main page of Dive and Discover and look for other interesting expeditions (under “Choose an Expedition”) or study sites (under “Dive into Deeper Discovery”). But this doesn’t mean that you always need to travel miles away to find an interesting ecosystem. Just look around you and I am sure you will find wonderful places to explore.

What do you do with your findings? Devin B. of William Diamond Middle School in Lexington, MA, asked the same question some days before (Mail Buoy 12/2).

Well, the outcome of all analyses will be communicated in the scientific literature. In this website, we are trying to present the findings in a more simple-to-understand way. That’s why we encourage students to send their questions to the Mail Buoy.

Concerning our diet, we eat very well on board! Just go to mail buoy of 12/3 (Praskovia's question) and to the “What’s to eat?” link on the Daily Updates where you can see all the goods we get. Also, go to Sunday’s slideshow to see some wonderful pictures of people who take care of our diet.

Hi,
I was wondering what kind of filter your new in situ sampler uses. Does it filter selectively for protists or all microorganisms? Also, does the filter get fixed at the sampling site or do you have to remove, fix and stain it on the boat? Thanks!

Our in situ sampler uses polycarbonate filters that have a 0.65-micrometer pore size. This pore size catches all protists and bacteria except for those protists that lyse, or break up, upon filtration and those bacteria that are very small (under 1 micrometer in size). The filter is fixed at depth, or "in situ," hence the name “in situ sampler.” We perform different stains of nucleic acids and enzymes on the filters after the sampler is brought back on board the ship.

Hi, If these organisms can tell us where we might look for life on other planets, how will this information benefit scientists? What can it lead to?

Vishnu Murale
William Diamond Middle School
Lexington, MA

Hello, I am a student in Ms. Sheild's class. It was said that these protists are suspected to be one of the first organisms to live on planet Earth, are there certain qualities that the DHABs have that would help life to form out of non-living substances? Thank you so much for answering my questions and many others.

Extremophiles are organisms—mostly unicellular—that not only live beyond the environmental conditions that we, humans, live but also they require these extreme conditions for their growth. The investigation of these microorganisms provides us with clues on how life can be “as we do not know it.” For example, due to their high salt concentrations, the DHABs leave very little water available for the bacteria and the protists that live there. If we can prove that these extreme organisms are alive and kicking, then we might be able to unravel the mechanism on how a cell can survive with little or practically no water around it! Water is considered as a prerequisite—if not the most crucial ingredient of all—for “life as we know it on Earth,” but available water is rather scarce in the planetary bodies we have studied so far. So, now you can see some common features between microorganisms in DHABs and their extraterrestrial cousins (if they exist).

Hi, I am a student in Ms. Sheild's seventh-grade science class. I was wondering if protists in the DHABs have to be constantly moving, and if they're not constantly moving, would they float at the top of the DHAB as humans do in very salty water? Thank you for taking the time to respond to my question!

Very interesting question! Thank you for asking, Sonia. Protists move in the seawater in relation to changing growth-related environmental factors such as light, nutrients, prey, organic carbon. In DHABs, they probably do the same in order to find their prey or avoid their grazers for example. “What happens if they stop moving?” We don’t know if and how they can regulate their buoyancy in this high-density environment. Probably when they stop moving they float at the “surface,” that means close to the halocline (the interface between the brine and the seawater) where bacteria—their potentially favorite prey— thrive. Further research is needed to understand the survival strategies of protists living in these extreme environments. We hope we'll get the answers in the future.

While you are on the expedition, are you spending the whole time at sea? Are you going to land at all?

Hello, Abby,
Yes, we spend the whole time at sea! If something serious happens, we may go to land. It happened to me twice. The first time was on a cruise in the Atlantic, when the cook broke his leg. The vessel had to dock in order for the cook to get medical treatment and also to be replaced by another cook! The second was in this cruise, when we had to deviate from our course in order to lead the rescued men to Kalamata port. However, even in these cases, crew and scientists are not allowed to disembark! So, we did not step on land since the beginning of the cruise.

Jason is mostly made of aluminum with some stainless steel and titanium. We put zinc all over the aluminum to keep it from wasting away. We are also very careful about inspecting it when it gets to the surface and thoroughly washing it off with soap and water. We are unable to make Jason sink very deep into the brine and we are unable to see much as soon as we get into it. We are mostly sampling the interface between the brine and the regular seawater. So we don't spend much time in the actual brine.

From Cathy Offinger, Jason team member:
In 2002, I was on a project in the Solomon Islands, looking for the remains of John F. Kennedy's PT-109. We were using an Australian fishing boat, the Gray Scout, which we had converted to our research platform. After a successful mission, we packed up and secured our small remotely operated vehicle and all our gear, said farewell to most of the scientists, and took off to return to Gladstone, Australia (about 100 miles north of Sydney). There were four of us from the operations team in addition to the boat's captain and crew. Within 24 hours of our departure, we were being chased by a typhoon. We were all ordered to remain inside. It was far too dangerous to go outside. Twenty-foot seas were pushing and twisting us along. It took every bit of strength to stay wedged in our bunks, so we wouldn't be hurled across the room.

The ship's crew was not doing any better than the rest of us. The captain basically stood 24-hour watches to drive his boat. The cook managed to get up long enough to throw some food on the table three times a day for those of us who were not seasick. I don't recall what we ate, but I do know I was one of a very few who managed to reach the mess deck.

The sun shone brilliantly throughout our passage (which took five days!) which made it seem not so bad. Once we were safely back at the dock, I recall looking at the old wooden hull of Gray Scout and marveled that it actually made the transit and that we all had survived.

From Tito Collasius, Jason Expedition Leader
On my last cruise on the Atlantis, we experienced many storms. That was in the Pacific and the closest storm was Hurricane Jova. We had to keep Jason out of the water and tied down on deck and anything loose on the ship had to be tied down. It is pretty hard to sleep in very rough weather.

How did you guys build the submarine? Since it probably had to be really close to the density of the water in order to explore the deep brines.

Elizabeth Wong
William Diamond Middle School
Lexington, MA

Hello Elizabeth,
We built Jason back at Woods Hole. We had built a few remotely operated vehicles before and learned quite a bit from each one. We took the lessons we learned and asked all of the scientists what they would like and went from there. As far as getting the weight right, we ballast the vehicle differently for each dive according to the depth of that dive, using steel plates.

Abby B.
William Diamond Middle School
Lexington, MA

Dear Abby,
We filtered water from the halocline and brine over paper filters with 0.65 µm poresize. Protists were held back. Now we can isolate their genetic information and analyze their genetic code. Based on that we will be able to construct small gene code pieces, which we can connect to fluorescent dye. Under a special microscope we will be able to identify exactly those protistan cells from which we had before just the genetic information.

Can you imagine: Just with some genetic letters "AGTGGTGTTT..." we get to the protists and see their shapes.

But this is only one single aspect in the many upcoming projects that follow our expedition.

Lea Weinisch & Dr. Alexandra Stock
Technical University of Kaiserslautern,
Germany