Dive and Discover : Expedition 14 : Mail Buoy, December 3

Read questions and answers in the Mail Buoy

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Hi Cyrus,
Thank you for your question. We assume that you are meaning organisms instead of organelles? Because organelles are only the "organs" of single celled organisms.

If the question concerns organisms, our answer is the following:
Because of the very harsh environment (high salt, high pressure, no light, no oxygen...) only those organisms with high specialization can survive and thrive. For all the others living and metabolism is not possible. The adapted creatures have developed mechanisms over thousands of years to transport salt out of their bodies, or they get along with very small amounts of nutrients over a long time, and their cell interior is chemically different from those which are more familiar to us. How the mechanisms work exactly is obviously not clear, so to find that out is one of our many motivations.

If minor or major setbacks occur, when would the assumed finishing time be? Also, if you find that there is life that could maybe survive in outer space, would you send another expedition to put those organisms in space to test the theory?

I wish it were up to us to determine our finishing time, but the way it works is that we applied for funding from the National Science Foundation, and they awarded us a set number of ship time days (that we requested). Ship time is very expensive, so we try to be as efficient as we possibly can. If setbacks occur (as they almost always do) then some of the objectives get cut out of the schedule, hopefully retaining the most important ones.

If we discover life that might be able to survive on another planetary body based on similarity of environmental conditions, that information can be used by others who look for life on other planets to inform them where to look, what types of life to look for, and possibly some unique biosignatures of such life. It is probably unlikely that scientists would try to intentionally bring such life forms to other planets. It might turn out to be a similar problem as "invasive species" that you probably have seen around where you live--non-native organisms can have detrimental consequences for local ecosystems. But you never know! Thanks for the great question!

Dr. Edgcomb

The depressions in the seafloor that become brine lakes can be formed in various ways. In the eastern Mediterranean, where we are, they developed in one of two ways. Both involve tectonic activity, or the movement of continental plates in relation to each other.

In the first, movement along a fault line where the plates moved sideways in opposite directions opened a gap that became a deep basin. In the second, the plates moved toward each other. That caused the seafloor to fold and develop cracks. Some of the cracks were deep enough to allow seawater to go far below the surface and dissolve some of the massive salt deposit there. Eventually enough of the salt deposit had been dissolved away that the seafloor collapsed. It was like a sinkhole on land. The collapsed area became the basin, and since it was in contact with all that salt, over time it became hypersaline (ultra-salty).

When you have found the protists, how would you know the unusual factors that allow the single-celled organisms to stand in the brine lakes? How would you identify them, and if you do, about how long would it take?

Michelle, you are actually asking the same things that scientists have, regarding the brines! The “unusual” factors that you mention have to do with the extreme conditions--at least we consider them extreme for all other creatures--that prevail in the brines: high salinity/conductivity, lack of oxygen, high hydrostatic pressure (i.e. depth of about 3500m). All the “simple” questions you posed demand enormous, laborious, costly and time-consuming scientific work. So, for this cruise we are targeting to identify with molecular methodologies which are these protists and which of them are active. Through the Dive and Discover website and other questions and answers on the Mail Buoy you will find more details on how we aim to do this.

Our work, which includes several scientists, will last 1-2 years after the end of the cruise while some further analyses might be needed as results from the samples we are collecting right now start to give us a more complete picture. As our research proceeds, more scientists might be interested and be willing to help through their skills. And of course, we are all looking forward for young bright minds, like you and everybody who are sending questions to us, to join us in such quests.

1. What other things do you think you might find there?
2.Why do you think the water is that salty?

Hello Jessica,
Regarding living things, we do not expect to find any larger or more complex (i.e. multi-cellular) organisms than protists. But of course there are prokaryotic microorganisms, namely Bacteria and Archaea, that we know for sure live in and around the brines. Regarding non-living things, we haven't seen much. During one of my JASON watches, we came across a plastic fruit basket! Be sure, Jessica, if we see anything really unexpected you will see it on the expedition's web page!

As far as why the water is so salty, the Mediterranean brines are a kind of special habitat. In the webpage of Dive and Discover Expedition 14, go to the second paragraph, it is all explained. If it still is not clear let us know!

We don't have an objective tied to a number of organisms, because most of the organisms that we are interested in are microscopic, so we will only know their numbers once we are back in the laboratory. We are hunting for some metazoa in the sediments, but again, with little time for microscopy and careful observation of the sediments on the ship, we may have to wait to find out all what we have collected!

Cheers,
Dr. Edgcomb

Hi Sue, this is a great question. Sulfide is an ion of the element Sulfur, and in the types of environment we study it is usually bonded to hydrogen, HS- in dissolved form, and H₂S in gaseous form. It is not dangerous to bacteria, archaea and microbial eukaryotes that are used to living in the presence of it, but for most organisms it is highly toxic, inhibiting/interfering with the respiration chain, and is only tolerated in very low concentrations. The concentrations of sulfide found in some of these DHABs is well beyond the limits of tolerance for most eukaryotes. It only hurts creatures in the sea that are not used to sulfide exposure and suddenly find themselves exposed to it and unable to move away from it (for example during a sub-sea volcanic eruption perhaps, or falling into a sulfidic zone).

Hi Michael, I presume you are referring to the SID-ISMS that is being used for water column operations? If so, construction of the machine began late last spring, and finished 2 weeks before we had to ship it to Greece. Design of it started 9 months prior to that. If you are referring to Jason, then send another question and we'll send that question to the Jason group.

dvir
Diamond Middle School Lexington Ma

Well, we are getting lots of exciting samples here. I imagine we are getting lots of rare protozoa, but it is too soon to tell about them. We will only know what we have when we are back in the lab and can look at them under the scanning electron microscope, and can look at their gene sequences. During the Jason dives we have collected some exciting muds with what looks like bacterial mats on them. If so, these would be some of the most extreme bacterial mats ever found: basically a carpet of possibly filamentous bacteria living deep in the ocean in a hypersaline, anoxic, and sulfidic environment. Stay tuned for more discoveries!

Well, regarding the Jason sediment surveys, the best thing would be for us to be able to locate the brines, see them, survey them, take lots of pictures and samples of the sediments, and to go home and find interesting living organisms (or ones that WERE living) in them. So far, all has been accomplished aside from examining the sediments, which will happen back in the lab.

Regarding the water column work, the best thing would be for the SID-ISMS to start working as well as we hoped it would, and to return with a well-preserved set of in-situ collected and preserved RNA samples. We are not there yet, but are working hard toward that goal!

Cheers,
Dr. Edgcomb

If the DHABS can conduct electricity well, is there a way to map the bottom with electricity

This is a good question Tomasz. The ship uses several systems to map the ocean floor in the area where we are working. One way is using multibeam sonar, which uses sound velocity much the way bats locate prey and other objects. In fact, the multibeam sonar on Jason is called the Sea BAT.

The density of the brine of course conducts sound (and electricity, another form of energy) differently than ordinary seawater, which complicates the ship's ability to calibrate exactly how deep the ocean floor is below us. Catie, the SSSG technician on the ship, calibrates this by conducting an XBT before their mapping efforts. “XBT” stands for “expendable bathythermograph.” It measures temperature, and based on calculations of time and salinity, it can give us a sound velocity profile as this expendable unit descends through the water column, hanging from a very thin copper wire.

I am a student in Mr. Carter's 7th grade class. How has the rescue of the 93 men effected your schedule?

Well, obviously it was a wonderful thing to be able to do. We wouldn't trade that for anything. But it did set back our science by a full 24 hours. I have had to cut out a few of our sampling efforts as a result. Small price to pay for saving lives, right?

Yeah, acutually I did see some interesting deep sea creatures on this cruise for the first time in my life. When I had watch in the Jason Van and they dived near the halocline of the Urania basin, we saw a big black fish which mostly looked like an eel. So its body was long and slender with fins that were not extremities, but closely attached to the fish's body. This fish may have been 60cm in size. It seemed kind of curious and sneaked very slowly around Jason's robot arms and all the equipment.

During another dive, I saw a completely different fish, again near the halocline of Urania. This second fish was only about 10 cm in size, very compact, and pink. No dark spots were visible where normally eyes are seated. And this one did not give us the favor to swim around the cameras, instead it vanished after a few seconds.

Thank you very much for following our expedition,
Alexandra Stock
Technical University of Kaiserslautern,
Germany

hi Mrs. Edgecomb! we all heard about the news about the Egyptians thats very exciting i hav a question, is it at all hard to adust to the bumps and waves of the ocean and also hows the cruiz going did u find what you are looking for?

For some people it is hard to adjust. The first night was kind of rough, and so a few people were feeling a bit "woosey." But Atlantis is a big ship, so it is not too affected by big waves. Nonetheless, it usually takes a day or two to adjust if one is not used to it.

I think we are finding what we are looking for! When one is targeting things that are mostly microscopic it is sometimes hard to tell, but all signs are good!

Cheers,
Dr. Edgcomb

When you find out, what temperature was it at the saefloor? What is it normally? Does the temperatureaffect the DNA samples?

Usually, the water at the bottom of the ocean is about four degrees C. This is because at this temperature, water has its highest density. This means that at four degrees C one liter of water weighs more than at temperatures above or below four degrees C. As a consequence, this four degree C cold water sits at the bottom. This is indeed different for the Mediterranean. In the Med Sea you will hardly find any water that is as cold as 4 degrees C. This is because the input of new colder water from the Atlantic Ocean is very limited (through the Strait of Gibraltar between Spain and Africa) and the water that is currently in the Med Sea has been warmed up for many, many thousands of years. Therefore, the water at the bottom of the Med Sea is about 14 degrees C. When I first found out about this fact on a Med Sea expedition several years ago, I was quite surprised about this fact, too, and that is why I liked your question a lot. This high bottom water temperature makes the Mediterranean Deep Sea a quite unique habitat.

Hi, I'm a student in ms Sheild's class at Clarke Middle School. Plant cells on the surface have chloroplasts to be able to use photosynthesis to make food. Producers in the deep ocean use chemosynthesis to get food, but what i want to know is what is the equivalent of a chloroplast in a protist or prokaryote living in the deep ocean?

I am surprised about your excellent knowledge on the different modes of energy production. I like your question very much. Protists are a large group of organisms. Basically, all unicellular organisms that have a cellular nucleus are called protists. Among them are many, many species that carry chloroplasts to conduct photosynthesis. These species are usually unicellular algae that are widespread in marine waters and also in freshwater. Some protists do not have their own chloroplasts, but they steal them from other organisms. Some, for example, feed on algae and they use the chloroplasts of their prey to make photosynthesis for a while. Others that do not have their own chloroplasts may harbor symbionts with chloroplasts. Prokaryotes, in contrast, do not have chloroplasts. But they have the pigments that are organized in the chloroplasts of protists and higher plants. With these pigments they are capable of performing a very efficient photosynthesis just like algae or higher plants.

I am in Ms. Sheild's 7th grade class and i was wondering in the DHAB what kinds of protist are there, are they animal-like, plant-like, or fungus-like?

Hi, I'm a student in Ms. Sheild's 7th grade class. I know that some plankton float up to the surface of the ocean from fairly deep down. Are there any organisms that float up from really deep down where there is no sunlight, and use both chemosynthesis and photosynthesis for their life processes? Thank you for your time.

Krishna S.
Clarke Middle School, Lexington, MA

Hello Kenzie and Krishna,
Well, so far we have found both protists and fungi. The protists are commonly dinoflagellates, ciliates and kinetoplastids. We hope to find additional types of eukaryotes, including some novel protozoa.

On the contrary, since light cannot reach the deep ocean, we do not expect to find any phototrophs.

What if these organisms float on surface? There is an interesting hypothesis that says that “everything is everywhere, and the environment selects.” This means that microorganisms are ubiquitous (live all over) but thrive only where they find their favorite environment.

However, we do not really know if there are organisms that can survive the stresses of DHABs and come to surface for what we would call a “normal” life. We also suspect that not all types of eukaryotes can be found in all types of environments, particularly more isolated environments such as the DHABs.

Hello Praskovia! We eat very, very well on the ship. The steward (head man in the kitchen), Larry Jackson, and his staff are great cooks. They stock up on food when they are in port, and they store it in a walk-in refrigerator, a walk-in freezer, a dry goods room, and a pantry. The hard part for us is that they give us so many good things to eat at every meal that it is hard to choose! Do I want the barbecue ribs or the Greek stuffed chicken? We get plenty of fresh fruits and salads and yummy desserts. And if we’re up all night working, we can drop into the mess (the dining room) and pick up a snack.

Every day the Daily Update page has a link to the menu for that day’s meals, so you can see what a great kitchen staff the ship has.

Dear Vanessa, thank you for your good question. If we deploy our instruments to sample the brines, it takes them about 70-80 minutes. Our cable winch to which our instruments are attached works at a speed of 50 meters per minute. I have been on other research vessels which much slower winches. In these cases it took us about three hours to arrive at the halocline with our samplers.

How would you expect the organisms living in the brine lakes to benefit from symbiosis, and what kind of symbiosis do you think it would be?

Dear Luke. Thank you for your very smart question. This is actually something we want to find out during our project. But we already have some basic ideas of what we could expect to find. The extremophile organisms in the brines have to cope with harsh environmental conditions, such as toxic substances like hydrogen sulfide which inhibits the respiration chain. For detoxification, some protists may be dependent on a symbiosis with bacteria.

We assume that symbiosis is a very important survival strategy for extremophile protists and we are very eager to learn more about specific kinds of symbiosis. If you keep track of our project, you hopefully may learn more about our novel (symbiosis) findings in the near future.

Hello. My question is when the Jason or the other vehicles, how can you keep track of them? How can you make sure that you don't need to check every minute?

Hi Michelle,
Very good question. We have water detect systems in all the junction boxes. If we got water in one of them an alarm goes off. Also we have gauges that show us pressures of the various systems. As long as we are showing pressure with no changes we know the systems are intact. Those gauges are monitored by the people operating the system via one of the video cameras on Jason. Also we are always looking down on Jason from a video camera mounted on Medea. That gives us a very good look at Jason, kinda like a helicopter watching traffic.

Do you stay in one place or do you gradually move around every day to take new pictures and videos? If so, how much do you move around?

The ship stayed at about the same place above the Urania Basin from Saturday until Thursday night. That allowed the scientists to sample and explore one part of the basin multiple times. The remotely operated vehicle Jason went to a couple of different places along the edge of the basin, but it also had to return to the same site it had visited before in order to pick up the injection cores it had left there.

Last night, the ship moved about 10 nautical miles eastward to a position directly above the Discovery Basin. Now we will stay here for a few days while Jason and the SID-ISMS explore here. There is plenty to see and sample in one small area, as you can tell from our photos and videos.

There are two ways you can track where we are: Every day, in the weather report on the Daily Update page, we list our latitude and longitude. Your teacher can show you how to use those numbers to find where we are on a map. The other way is to go to www.whoi.edu/page.do?pid=8231, where the position of R/V Atlantis is shown on a map.

Since the brines are so dense with salt they form at the bottom of the ocean but the dead sea in Israel is also salty but it is like a regular ocean. If its also salty, how come its not at the bottom as well?

You are absolutely correct that the Dead Sea is also very salty. The Dead Sea is an inland sea. It loses lots of water by evaporation but this water is not replaced by water from other sources including rain and connections to other oceans. While the water evaporates, the salts accumulate in the remaining water of the Dead Sea so that the salinity is steadily increasing. As saltier water is heavier than less saltier water, you also in the Black Sea will find a gradient of increasing salt concentration towards the bottom.

The brines in the Mediterranean Sea have a different origin, namely through the dissolution of ancient subterranean salt deposits. Once the normal saline Mediterranean water got into contact with these salt deposits, they started to dissolve. As they are heavier than the normal Mediterranean sea water, which is fed by the Atlantic Ocean, it sits on the bottom, right at the spot of its origin. I hope this answered your question.

There are 22 ships crew, 2 Ships scientific support technicians, 9 ROV/Jason crew and 17 Scientists.
Does that equal 50 total? I hope so :)

dr edgcomb its Jd S. hope your cruise is going well i thought it was amazing when you and your ship rescued those people i wanted to know if you have found anything or if you have had any problems with your equiptment

We have found lots of interesting things. For instance, mats made of microbes that live on the sediments at the edge of these brine lakes. Also a few scientists have observed some animals (something eel-like, and maybe a small fish and a shrimp) swimming near the halocline. We'll have to take a closer look at our videos. We have collected lots of exciting sediments and water samples to look at under the microscope back in the lab, and to conduct a variety of other experiments with. Yes, we are having troubles with our new water column sampler, but we are working almost around the clock the last few days to get it to work. We are hopeful.