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!