A day in the life

Drawing from original draw-a-scientist study in 1983. Photo By Yewhoenter (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

Drawing from original draw-a-scientist study in 1983. Photo By Yewhoenter (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

At the beginning of my graduate school career I remember sitting in on a seminar about a recent program implemented by several students called “draw a scientist”. Students involved in a GK-12 program, where graduate students bring science to middle school and high school classrooms, were asked to draw their version of a scientist. In the drawings, crazy hair, flasks, and lab coats were a common element. Students described their scientists using adjectives like smart, crazy, chemicals, mixing, nerd, weird, lab coat, old, lab work, hard-working, and cool. At that age, I probably would have drawn the same thing, except my scientist would have been female, and I would have most definitely included the word “cool” in my description. However, my experience as a scientist has not led me to don a lab coat very often. I have held a few jobs that included pristine labs with white, crisp coats and flasks, but more often than not, I am wearing muddy waders, hiking boots, or dive suits.

Fishing for crabs on the York River.

Fishing for crabs on the York River.

I am a marine scientist, and I study the interactions between animals that live in the ocean. Right now I am studying predator-prey interactions in the Chesapeake Bay, which is not exactly the ocean but it is pretty salty. It is an estuary, where the rivers from the land meet the ocean and a mix of fresh and salt water occurs. The Chesapeake Bay is home to many species found in the Atlantic, as well as some that are only found in estuaries. I am focusing my research on two predators, the blue crab and the cownose ray, and a few of their prey species, including the soft-shell clam (steamers in New England), hard clams (or quahogs), razor clams (often used as bait), mussels, and Eastern oysters. My research is attempting to answer the question, how will these predator-prey interactions change in the future as climate change impacts the Chesapeake Bay in various ways?

Scientists never really prove anything; they can only provide supporting evidence for a phenomenon, and as the amount of evidence grows, so does the scientist’s confidence that their answer is correct. Thus my research project that I am completing for my PhD will collect a variety of evidence to answer my research question. I have to look at the problem in a number of different ways, using not only experiments in the laboratory, but also observations and experiments from the Chesapeake Bay itself, and predictions from mathematical models. That is why getting an advanced degree in science takes so long and involves so much work. Scientists-in-training are learning how to build a body of evidence to try and answer a research question. When completed, my dissertation will consist of four different chapters which summarize eight (or more) research projects, all designed to provide some evidence pointing towards the answer of my research question. In the end I still won’t have an answer; just a starting point and a hundred more questions. Remember, science is a journey.

IMGP6708

Suction sampling using a large pump to collect clams.

So what do I actually do? In the summer I go out on some rivers that feed into the Chesapeake Bay, like the York River, in a small boat and collect samples in shallow water. Most of my samples are suction samples. To take these samples I use a large pump that works as an underwater vacuum, allowing me to vacuum up the mud and sand on the bottom of the river. I use these samples to understand how many clams are in an area. I also tow nets behind the boat to collect fish and crabs (the predators in the area), and snorkel along a 50 m rope laid out on the bottom of the shallow parts of the river to count the pits that rays make when they feed. This is a much easier way to figure out how many rays are in an area than actually catching the rays.

Photo from a clear-water day in the Chesapeake Bay.

Photo from a clear-water day in the Chesapeake Bay.

The water is mostly muddy but every so often, when the conditions are right, I feel like I am snorkeling in the tropics. Those are the best days, when I get to see vast expanses of seagrass, the terrapins (a type of swimming turtle that gets about the size of a dinner plate) swim next to me, and I can see all of the little clams and worms on the river bottom going about their business, excavating burrows and spewing out streams of mud that look like something that comes out of a Play-Doh pasta factory. But most days I can only see about a foot in front of my face, and the view is frequently obstructed by translucent jellyfish tentacles that appear too late for any sort of evasive maneuver, and the resultant burning pain is just treated as part of the overall experience. Hey, it could be worse. We could be in our office.

For the rest of the year I devote my time to a number of activities. These include sorting through the suction samples to pick out the clams, holding an active leadership role in graduate student government, keeping up to date on the latest science discoveries in my field, fulfilling my current funding requirements (this year, I was a guest scientist in a 7th grade classroom for a couple of days every week), writing grant proposals to fund my education next year, writing reports (and soon my own scientific articles to be published in a journal), and working on a project in the seawater laboratory (see video).

I visit the seawater laboratory every day of the week, devotedly, except for Sunday. All of my critters (blue crabs, clams, mussels, and oysters) seem to behave on Sunday. However, if I fail to visit any other day of the week, disaster abounds. I return to rampant cannibalism (in the blue crab tank, of course), escapees, clogged plumbing, leaky ceilings, broken water heaters, overflowing tanks, you name it. For a while I was convinced that the brand-new seawater laboratory was haunted. Now I know that this is just one of the things that makes ecology so interesting and exciting. Since I am always working with live critters, things never really go as planned. I have spent most of my time in graduate school anticipating the evil intentions of invertebrates, some of which don’t even have brains. As a result I have had many chances to exercise creative, out-of-the-box thinking, and when I fail, the consequences are usually pretty hilarious.

I mark clams with marker before placing them in the river, so if I get them back I know they are from my experiment.

I mark clams with marker before placing them in the river, so if I get them back I know they are from my experiment.

For instance, last summer I was running an experiment in several tanks where crabs were offered clams for food. There were various scenarios that made it harder to get at the food (i.e. clams were hidden underneath a layer of shell), and crabs are lazy, so it shouldn’t surprise me that the crab starring in this story had had enough, and was ready to strike out on his own to find a more promising food source. Despite precautions to prevent this type of thing from happening, the crab climbed out of the tank and into an adjacent tank. This rarely happens; the tanks are round and only overlap for a small portion, but in this case the crab was on a mission and the result certainly paid off. The day before I spent 8 hours with a volunteer painstakingly marking clams and placing them in containers to be deployed in the York River the next week. The crab had discovered a buffet of epic proportions, and the next day  I arrived in the lab to find shell splinters and an extremely well-fed blue crab.

Catching a carp for fun while on the job.

Catching a carp for fun while on the job.

My experiences may not be typical of the average scientist, but I would argue that white lab coats are not typical of the average scientist, either. Scientists are just as likely to be “outdoorsy” as they are likely to be holding chemicals over a Bunsen burner. Programs like GK-12, sponsored by the National Science Foundation, help to inspire the next generation of scientists and to change the way people think of scientists. As a result these programs produce a more diversified next generation of scientists, and hopefully increase public trust in science programs. This is especially important because public trust in scientists is very low. This should be very concerning for scientists, a group of people who base their lives and careers on a quest for truth.

Not-so-streamlined science

Longhorn cowfish. Photo courtesy of H. Zell (Own work) (http://www.gnu.org/copyleft/fdl.html)

Longhorn cowfish. Photo by H. Zell (Own work) (http://www.gnu.org/copyleft/fdl.html)

Welcome to the Cowfish Blog! You may have heard of a cowfish before, or maybe not, but two things are certain- cowfish are REAL and they look strange compared to most fish. I figured I would introduce my mascot in this first post, and in doing so tell you a little bit about this blog, and science in general. So first, let me introduce my guest of honor, the cowfish.

You may notice a couple of things about the cowfish that stand out as strange. It is shaped like a box. That boxy shape is made of bone, which makes the cowfish much larger than would be necessary to simply contain its innards. This makes the cowfish, which tops out at about 20 inches in length, one of the largest fish around on the coral reefs, where it makes its home. That is excluding the sharks. And the groupers. In any case, it is large, which means it is noticeable if you go snorkeling in the Indopacific, especially because it is bright yellow. Its coloration makes it stand out to tourists, and also to predators. The cowfish doesn’t have to worry about standing out to predators because it has a couple of ways to defend itself. First, it has horns. These horns make it too large to fit in the mouths of most fish, which means only very large predators can hope to make a meal of a cowfish. Second, it is toxic. When a cowfish feels threatened it secrets poison from its skin, and this poison is very dangerous to other fish. This means that a shark that bites down on a cowfish might seriously regret the meal. Cowfish poisoning will first cause disorientation and erratic movements, then coma, then death. It is even toxic to mammals, though it takes a lot of toxin to affect humans. Cowfish toxin can have an indirect effect on humans that keep fish in aquaria, and have a sick cowfish kill an entire tank of fish in a night. Speaking from experience, of course.

Front view of a longhorn cowfish. Photo courtesy of I, Drow male GFDL (http://www.gnu.org/copyleft/fdl.html)

Front view of a longhorn cowfish. Photo by I, Drow male GFDL (http://www.gnu.org/copyleft/fdl.html)

I think most people would agree that a cowfish looks like a very slow swimmer. In fact, cowfish are fairly fast swimmers that can swim long distances using little energy and with great stability. They swim using movements from their fins only, since they can’t bend their bodies. At slow speeds the tail is used for steering, like a rudder. Their body shape can automatically correct any tips and dips that happen when waves sweep over the coral reefs on which they live. That is because all of the edges of a cowfish’s boxy frame stick out in a flat plate similar to the keel of a boat. Boat keels are designed to keep the ship stable in the water and to help prevent it from tipping over, and a cowfish keel works the same way. In addition to providing stability, all of the protrusions on the cowfish’s body interrupt water flow from pretty much any direction and push the water away from the cowfish, making for a smooth ride. This is similar to what happens to a delta wing aircraft in flight. Delta wing aircraft are designed for maneuverability, and so, it seems, are cowfish. Cowfish can turn on a dime and swim upside down, which are adaptations that allow them to explore all of the hiding places in a coral reef. As I mentioned, cowfish are also extremely enregy efficient swimmers. Boxfish (a relative of the cowfish) use about as much energy while swimming as a sockeye salmon, a fish built for traveling long distances. In fact, cowfish swimming is more efficient (at pretty much all speeds) than the smallmouth buffalo fish, a carp that lives in the Mississippi River and has a much more typical fish shape.

Mercedes-Benz Bionic. Photo courtesy of NatiSythen (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

Mercedes-Benz Bionic. Photo by NatiSythen (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)]

The cowfish body design is so efficient that engineers often turn to the cowfish for inspiration. One application of the cowfish body shape could be a more energy-efficient design for a stable underwater vehicle. DaimlerChrysler AG actually designed a concept car based on the body shape of the cowfish and its relatives. This car, called the Mercedes-Benz Bionic, was introduced as a highly energy-efficient vehicle in 2005. It can go from 0-60 mph in 8 seconds, which is 0.1 seconds LESS than the Jaguar S Type 2.7d V6 Sport introduced in 2004. Clearly there is a lot that can be learned from the cowfish.

Illustrations of cowfish by Ernst Haeckel, 1904.

Illustrations of cowfish by Ernst Haeckel, 1904.

One thing we often don’t think about (or maybe you do, in which case you MAY be a biologist) is how did the cowfish get this way? Over evolutionary time (we are talking hundreds of millions of years) fish are exposed to different pressures that they must be able to survive in order to persist as a species. These include predators, finding food, finding mates, and a variety of other things. So which of these pressures caused the cowfish to look the way it does, and why did it respond to these pressures differently from every other fish? Certainly other fish can avoid predators by hiding or using camouflage, and it seems like the cowfish sure wastes a lot of energy developing its bony armor and toxins when it could have just covered itself in camo. There are plenty of other fish on the reef that are masters of maneuverability, such as the wrasse, and these fish don’t have to build up a boxy shape to accomplish amazing feats of hydrodynamics. So what caused the cowfish’s ancestors to develop its unique shape, horns, and toxins? Perhaps we will never know, but we can imagine that the route from a normal fish-shape to the shape of my most recent Amazon delivery was probably not a direct one. If it was, we would likely see it a lot more often in the animal world. I, for one, am glad that the cowfish’s ancestors took such a circuitous route to become the unique species it is today, not only because I appreciate cowfish for their adorable appearance, but also because I look forward to the day when I can travel underwater in a submarine built like a cowfish. Which may or may not be yellow. But I really hope it is yellow.

This leads me to the reason for naming my blog after the cowfish. The cowfish embodies many of the reasons why I love science. Science is weird and full of questions. You can spend your entire life as a scientist asking and attempting to answer questions. However the answers, when you do get them, are usually not direct, much like the evolution of the cowfish. As a result the quest for answers is a journey that leads the scientist to strange and interesting places. The end is something you probably never expected, but it is also immensely more interesting than you expected. I love that about science, and I love that about the cowfish. So stay tuned for some more not-so-streamlined science- my experiences as a marine scientist, and interesting tidbits about science and the natural world.

 

For more information:

Bartol, I.K., M.S. Gordon, M. Gharib, J.R. Hove, P.W. Webb, and D. Weihs. 2002. Flow patterns around the carapaces of rigid-bodied, multi-propulsor boxfishes (Teleostei: Ostraciidae). Integrative and Comparative Biology 42:971-980.

Thomson, D.A. 1964. Osctacitoxin: An ichthyotoxic stress secretion of the boxfish, Ostracion lentiginosus. Science 146(3641):244-245.

Gordon, M.S., J.R. Hove, P.W. Webb, and D. Weihs. 2000. Boxfishes as unusually well-controlled autonomous underwater vehicles. Physiological and Biochemical Zoology 73(6):663-671.

Bartol, I.K., M. Gharib, P.W. Webb, D. Weihs, and M.S. Gordon. 2005. Body-induced vertical flows: A common mechanism for self-corrective trimming control in boxfishes. The Journal of Experimental Biology 208:327-344.