Another week passed, and it’s been an exciting time! This week was very exploratory again and I learned a lot about trial-and-error and designing a new experiment from scratch. By the end of this week, I had set another experiment into motion, and I’m already collecting new data! Before the week began, we had another field trip! On Saturday, we drove two and a half hours north to Newport to tour the Hatfield Marine Science Center and walk around the Oregon Coast Aquarium. The tour around Hatfield was great, if a bit short. The campus was huge! Far bigger than the quaint OIMB. However, I’ve noticed that there are tradeoffs involved with Hatfield. The campus may have more resources and better technology, but they must trade off a degree of freedom by getting more oversight from the university they are attached to, Oregon State University. OIMB may be smaller, but we have a lot of independence on this campus, which I like. Additionally, from what I can tell, the sense of community is much stronger at OIMB. I prefer campuses like this, especially being so far away from home! After Hatfield, it was time to roll on out to the Aquarium. The Aquarium visit was short, but extremely fun! I saw so many animals that were native to the area. I saw jellyfish, seals, sea lions, and quite a few fish! All of them were so amazing in their own ways. After that fun weekend, it was time to go back to work! Monday was all about observation. I collected some fresh cyprids from the ocean and I watched them swim in a tall tank. This was like what I have done in the first few weeks, but I added a new method. I had read a paper published in 1928 that describes how cyprids respond to light cues. Going off that paper, I devised a method to get cyprids of B. glandula and B. crenatus to swim. I sat the cyprids in the tank in total darkness for 20 seconds, then exposed them to light for a minute. After a minute, cyprids should start to swim towards the light. After my observations, I’ve noticed some interesting patterns. Cyprids of B. glandula tend to swim straight up towards the light and keep swimming until they hit the surface. Then the cyprids would hover around the uppermost region. Meanwhile, B. crenatus would mostly remain on the floor of the tank, rarely swimming upwards. Occasionally, some individuals of B. crenatus will swim up the water column, but they rarely get to the same heights as B. glandula. Tuesday was all about turning these qualitative observations into quantitative data. My goal is to show, with numerical data, that the two cyprids exhibited different behaviors. I tossed around a few ideas on doing this. My original idea was to time how active a cyprid was in a minute of light exposure. Then, I would compare the proportion of time spent active between the two species. However, a logistical flaw came up with that idea; what is “active” behavior, and are the two species truly that different in activity? B. crenatus can be active, but they don’t necessarily move to any new place. B. glandula is very active, but they use that active energy to travel up the water column. A new idea was to measure the location of the cyprid in a vertical water column after a minute. I have already seen, visually, that cyprids of B. glandula tend to gravitate towards the top of the water column and cyprids of B. crenatus tend to stay on the bottom. If I can section off the tall container into thirds, then I can score the areas of the container and create numerical data from their visual location. For instance, if a cyprid of B. crenatus was on the very bottom of the tank, touching the floor, then they get a “score” of 0. If a cyprid was hovering in the bottom third of the tank, they get a 1, if they hover in the middle, they get a 2, and if they hover in the top third of the water column, they get a 3. With this new plan in mind, I spent the rest of the day that Tuesday preparing a black bottom for the large container, just in case the cyprids are seeing a mirror that is being produced in the tank. Wednesday was all about refining my methods. After a few attempts at looking at cyprids in a large tank, it quickly became apparent that it was going to be hard to see my cyprids swim. To rectify this, Richard and I decided to shrink the tank size down. To create better data, we decided to place pairs of cyprids into the smaller container, one B. glandula and one B. crenatus, to lessen the amount of visual chaos and to better link the data between the two species.
Thursday was a successful day. I went in to test my cyprid swimming behavior. I collected 10 cyprids of B. glandula and 10 cyprids of B. crenatus and paired the species up, so that each pair contained one of each species. Then, I placed the pair inside the tall water aquarium that was divided up into 3 vertical sections. Once in the tank, I had the pair become used to the dark for 20 seconds. At the end of those 20 seconds, I turned the light back on and exposed them to light for a minute. At the end of that minute, I marked where each member of the pair was. By the end of my 10 trials, I found that B. glandula overwhelmingly preferred to stay in the upper third of the water column, while B. crenatus tend to stay on the floor or the lower third of the column. Now, I am changing my focus to see how the cyprids of the two species change their behavior in response to different colors of light. Next week looks fun, as I get to throw a rave for my cyprids!
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Another week has gone by and it’s been hard work. This week was filled with problems and problem solving. My cyprids wouldn’t swim, the math couldn’t be worked out, and excel spreadsheets were looking chaotic. Admittedly, this week was rather frustrating, but that’s all a part of science. After all, creative problem solving is a vital skill in the sciences, and this week gave me plenty of practice. The thing is, even when you have a hard week full of “failures”, you still learn a great deal from those failures, and discover fun things along the way. Before the week began, Richard noticed that there was a flaw in the equation we were originally using to determine the density of a cyprid. In the original equation, we assumed that a cyprid’s depth was equal to the cyprid’s width, and we found a long, complex equation that was created based on that assumption. Then, Richard discovered a paper published in 2014 that showed that the cyprid’s width was, in fact, much smaller than their depth. Our assumption appeared to be flawed. So, this started a long trial of trying to find the right formula to get the most accurate density. A wild goose chase of nerdy proportions. I started the algebraic journey by remeasuring my cyprids. I had to carefully roll each specimen onto its belly to take an actual measurement of its width. Then, I spent the rest of the day finishing up my preliminary sinking and swimming trials for my B. glandula cyprids. Monday was all about measuring, brainstorming, and rocking my little cyprids. Tuesday is where the real trials started. With all the raw data in front of me, Richard and I had to figure out the new mathematical equation to use. I decided to go right at the source. I reread the paper that pointed out the flaw in our previous assumption and method, and I tried calculating density using their mathematical formula, which was a modified version of the Stokes’ equation. The Stokes’ equation is an equation that helps describe motion in highly viscous fluids. Think honey when you think of a very viscous fluid. I spent that day mostly inputting the data, calculating the new densities of my cyprids. As it turns out, there is a 10-point difference between the excess densities calculated with the old and the new method and this accounts for about 25% of their weight in water. I spent the rest of the day working on that spreadsheet, and then taking some breaks to work on my poster. I find that taking breaks from left-brain activities, such as figuring out math, to do more right brain activities, like organizing and designing an awesome poster, keeps me focused and prevents frustration. Then, Wednesday rolled around. I was ready to move on to conducting more trials with my other study species, B. crenatus. As it turns out, B. crenatus are a lot harder to work with than B. glandula. The first issue is with collecting my specimens. B. glandula are very common in plankton tows, and they’re relatively easy to spot and identify due to their characteristic golden color. B. crenatus are a bit less common, and their translucent coloration makes them hard to immediately spot. At least they have a large red compound eye that helps me spot them. I conducted a plankton tow on Wednesday and I could not find any B. crenatus. In the meanwhile, I continued working on my poster and organizing my data. Thursday is where everything complicated even more! Richard generously conducted a plankton tow early in the morning, so we may find some more test subjects, and we were able to find cyprids of B. crenatus. Invigorated, I conducted my swimming trials, only to find that all but two of my cyprids refused to swim. At best, a cyprid of B. crenatus will swim in a loop, but not at a great enough distance to allow me to measure their speed like B. glandula. I could at least measure sinking rates for B. glandula. Their “laziness” does appear to support one of my hypotheses about the difference between swimming activity between the two species.
After measuring sinking rates and body size in my B. crenatus cyprids, it was time to wade back into the mathematical jungle once more. This time, Richard and I realized that the 2014 paper failed to take the orientation of the sinking cyprid into account, which could affect density calculations. Our current solution is to take the average of depth and width of each cyprid and place that average into the old equation. Now the plan is to rework the data into this new method and see where my experiment goes from there. As for my “lazy” cyprids, I am looking far back into the literature, with a paper published in 1928 that describes the behavior of cyprids under various forms of light. Hopefully there I can find insights that will inspire my cyprids to finally swim. If after all that effort, if my B. crenatus cyprids still won’t swim, then that can still tell me something important, that B. crenatus are far less active than B. glandula. It’s been a long week, but with enough determination and cleverness, I am optimistic about the rest of my time here! Another cold week has passed, and my project has made numerous leaps and bounds since last week. The weekend was uneventful, no field trips to embark on! I took the weekend to relax and read a bit more literature on cyprids. During the week, I cemented my project plans and methods of action. Additionally, this week was all about learning how to present ideas properly as a scientist. On Monday, I spent most of my day writing and improving my proposal. Richard and I discussed how I should continue with my project idea of studying buoyancy in cyprids, but frame it around answering a question, or a proposed explanation, that was raised in a study conducted by Richard Grosberg in 1982. There, he found that cyprids of Balanus glandula were found higher up in the water column compared to those of Balanus crenatus. He suggested that these differences in distribution might be caused by greater buoyancy in B. glandula or higher sinking rates in B. crenatus. He also suggested that B. glandula simply may be more active swimmers than B. crenatus, which could explain their placement in the water column. My project address these points – buoyancy and swimming activity. Using a tank with very stable seawater (temperature-regulated water column set to around 54 degrees F), I will time how fast they sink. I will also time active cyprids to see how fast they swim. Then I will also observe cyprids and quantify how active they are. My project requires a lot of patience and focus, but with a steady hand, and a whole lot of coffee, I think I can do it! The rest of the day on Monday was spent setting up my special tank, so that the sinking cyprids won’t get any extra help or hindrance from convection currents. My cyprid sink and swim tank! The outer tank, covered with insulating Styrofoam, keeps the internal cylindrical tank at a temperature of 54 degrees F. This is so that convection currents do not form in the cylindrical tank. The light at the top of the tank encourages active cyprids to swim and allows me to see my specimens. On Tuesday, I collected fresh specimens of my two cyprid species with a plankton tow. I got a bunch of B. glandula, but B. crenatus was much less common. I practiced my proposed methods. I dropped a few individuals of B. glandula into my tank and watched them sink down, using my phone’s stopwatch app to measure the time it takes for them to sink two centimeters. I took two successive measurements of them sinking down two centimeters. It was hard to get them to sink in a way that wasn’t aided by the push of my pipette, but after some practice, I could gently drip them into my chamber and measure their descent.
On Wednesday, I discovered some issues in my project. These mostly involved the swimming tests. My original project idea was to perform sink and swim tests on the same individual, so that I can compare the two categories. However, I am no Doctor Doolittle. I could not make individuals of B. glandula perform both behaviors. Some individuals will only sink, some individuals will only swim. If I had more time and patience, I could wait for that special individual that would sink and swim in a reasonable time span, but my time here is limited. I had to do the two tests on different individuals. With that issue resolved, I turned my focus to sinking my B. glandula cyprids for the rest of the week. I tried setting up a camera with an excellent zoom lens to help monitor the action, but unfortunately the fog building up on the outer tank was too much. By the end of the day Wednesday, I was able to sink and photograph five members of B. glandula for analysis. By the end of the week, I should have 10 members sunk, and have enough data to start running some analysis on buoyancy, or in this case, specific gravity, on B. glandula. Another week as come and gone here at OIMB, and a lot has happened since writing my post last Thursday. Over the past weekend, all the interns and Maya joined with the other biology interns working at University of Oregon (in Eugene) to go camping and tide pooling at nearby Sunset Bay Park. It has been a long time since I’ve done any camping, and I’ve never gone tide pooling on the west coast before, so both experiences were fresh and new to me! The night spent in the tent was thrilling and cold, but ultimately restful. The next day, early in the morning, we left to go to Cape Arago for the tide pools. That trip was amazing! The morning was cold and dark. Even though I was armed with boots and a delicate sense of balance, I still almost fell on my rear while exploring the pools of water hidden within the rocks during low tide. Inside these hidden habitats were purple sea urchins, various species of hermit crabs, some porcelain crabs, various anemones, and even an extremely large chiton! A chiton is a type of primitive mollusk, and this large specimen was called the gumboot chiton, and it happens to be the largest chiton species in the world! During the tidepool walk, we trekked higher up the rocks to get a better look at barnacles, oysters, and urchin dugouts. The view and the animals were amazing. I can’t imagine what it’s like to live as an urchin among those rocks full time! During my work week, I hit a major snag in my previous barnacle cyprid project. After discussing it with Richard, I realized that my project idea wasn’t as feasible as I initially thought. Conducting microscopic surgery on a miniscule part of an already tiny organism would be too hard for me to accomplish during my time here at OIMB, and my other methods of staining and filming that body part also fell through. However, Richard suggested that I watched my various cyprid species swim around in a tall swimming tank. These observations, as well as a lot of reading of previous literature, helped give me a new project idea that was still related to cyprid anatomy and locomotion. I want to study the connections between locomotion and buoyancy of the various barnacle cyprid species that occur this time of year. Where this project will go specifically is still up in the air, but a newer, more feasible project has been chosen.
This past Monday, to work towards my new project idea, I read quite a bit of research on cyprid swimming behavior and cyprid distribution along the American west coast. Then, on Tuesday, I spent the day collecting cyprids of Balanus glandula and Balanus crenatus and then sat in front of the tank and watched them swim. B. glandula swam beautifully in the tank for me, but B. crenatus was a lot less active for me. B. glandula swam up towards the light that shined on the surface of the swimming tank, and they swam in a chugging motion up to the surface of the water column. A lot of their motion involves a brief burst of speed up the water column, followed by brief sinking motion, then another burst upwards. B. glandula touched the surface of the water but would almost never break through the boundary between air and water. They would then sink down towards the middle of the water column, repeating the motion again. For B. crenatus, it was much harder getting them to swim. They would either ride a convection current up the water column, sink down to the bottom of the container, or hover with a jump-sink motion in the middle of the water column. More work needs to be done to measure their swimming speed, sinking rates, and buoyancy and to observe their swimming behavior to understand their overall distribution in the water column. Hello everyone! It’s been about a week since my last blog post, and a lot has happened. Over the weekend, Richard, our sea captain Knute, and Richard’s graduate students Nicole and MacKenna took all the REU students on a trip to dredge for sea creatures on the R/V Pluteus. We started our journey early in the morning and the ride was rough and nauseating for practically everyone on board. After some time, and a lot of fortitude, we were able to collect many different fascinating creatures! We collected some sea cucumbers and peanut worms, enough to start a big and slimy salad! We also found basket stars, various crab and shrimp species, and some cockles. The dredging was hard work, but ultimately an exciting experience! The ride back to shore was even more nauseating, but after some fresh air, and an even fresher slaps of seawater to the face, I managed to keep down my breakfast. During my week in the lab, I had the main goal of practicing and perfecting my proposed methods of research, as well as prepare to write my proposal. At this time, I found that to study the functional morphology of the furcal rami, I needed to understand how to induce swimming behavior in my study cyprids. After doing some research using Eleanor Lamont’s master’s thesis, I learned that I can make cyprid larvae swim by manipulating light. Cyprids display positive phototaxis, which means that they have a behavioral tendency to swim towards sources of light. So, if I shine light upon my study animal, I can easily encourage them to swim for my observations. Next, I wanted to see how feasible it is to remove the furcal rami and still have the organism live from the taxing surgery. I conducted trial-upon-trial and eventually I decided that I currently do not have the tools or skills needed to remove the tiny furcal rami from the animal. What I could do, however, is safely remove the setae from that area of the animal and revive it. It takes an extremely steady hand to conduct this microsurgery. Its going to take many more attempts to remove setae, followed by revivals, to determine the feasibility of this procedure. If I can continuously remove the setae from the animals, then I will film their swimming behaviors with a high-speed video camera. A standard microscope camera (30 frames/s) is not quick enough to resolve the extremely fast thoracic appendages and the furcal rami. Finally, during my week in the lab, I attempted to study the musculature found within the caudal rami of the cyprid larva. The first try was simple. We removed the entire thorax from the organism and examined it on a microscope under polarized light. After a while of fiddling around with the settings, Richard and I saw some muscle bands leading from the thorax to the caudal rami. After confirming the presence of the muscle bands, we decided to try to stain the creature to see the neurons of the thorax. We used a common staining chemical called methylene blue in order highlight the neurons found within the thorax of the cyprid. Staining is an imprecise science, it’s quite difficult to gauge how long an animal, or part of an animal, should sit in the solution for full staining power. After quite a bit of trial and error, I figured that letting the thorax of the cyprid soak for four hours was enough time for the dye to bind to the neurons. However, after all that trial and error, I still couldn’t see the nerves well enough. So, my new plan is to remove the limbs individually and try to see their nerves. Science is all about the process of failing millions of times until you get the one right solution. All I can do is focus on the small victories and try harder next time. So onward to next week! |
AuthorHello, I am Savanna Cabrera, a fourth-year zoology major from the University of Florida studying barnacles. I’m an avid arthropod admirer. Archives
August 2018
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