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MISSION DISPATCH 6 June 7, 2005 | Steve Shotola | St. Lucie West Centennial High School TEACHER @ SEA Three words begin to explain the experience I am having on the Research Vessel New Horizon, forty miles off the coast of California, led by our chief scientist Dr. Tammy Frank of the Harbor Branch Oceanographic Institution: Awe, Amazement and Anticipation. 
I am in absolute awe of the scientific research being conducted with mesopelagic (organisms that live between 200 and 1000 m in the water column) organisms on the vessel. Being a high school marine biology, and biology instructor, one of my major goals throughout the year is to teach my students the numerous adaptations marine organisms evolved to best suit them to their environment. In this way my students better understand their own biology and the adaptations humans have undergone to become who we are. Watching and having Dr. Frank and Dr. Jon Cohen explain their research on how a marine organism's visual and photoreceptor spectral sensitivity have evolved to best suit an organism's visual environment in face of an enormous variation in the marine light conditions is powerful stuff. Often an organism has to choose, by natural selection, in the deep-sea low light environment (where most of the organisms are being collected on this cruise) between sensitivity and resolution of their eyes (photoreceptors). In order to increase the sensitivity of their eyes, they have to sacrifice resolution, so it's a trade-off. The picture is complicated when a species spends its early life history stages in the fairly brightly lit surface waters, and its adult stages in the deeper darker depths. Much of Dr. Frank and her students' studies are centered on if and how organisms adapt their visual systems during different life stages to those visually challenging and changing conditions. The animal they're particularly interested in off the coast of California is a crustacean called Gnathophausia ingens, whose juveniles live between 150 and 300 m, while the mature adults live below 650 m. Dr. Cohen is studying the visual system is a tiny crustacean called Gaussia princeps, which is found below 800 m, but still has functional eyes. 
Most of us live in an urban technological world, where our visual environment is artificially
bright and consistent. We lose our appreciation for the biological challenges organisms face
in a variable natural world. I foresee doing activities in my classroom where the light
intensity and spectral wavelengths are changed in the classroom in such a way that the student's
visual sensitivity and resolution is taken to the edge of their ability of detection (in much
the same way the organisms in the deep-sea are). My students will undoubtedly get a greater
understanding and appreciation of their visual acuity and better understand the physical
factors involved (wavelength, intensity, the science behind) needed to have the vision we have.
My students will gain a greater understanding on how the visual environment of the mesopelagic
marine environment is vastly different from ours, and understand how the organisms that live in
this environment have evolved their visual acuity in a much different way to ours to match the
environment they live in.
I find it amazing the meticulous procedures Dr. Frank has to undertake to collect her specimens in the mesopelagic zone. A trawl net is dragged and triggered to open at a controlled depth. The organisms are usually collected at approximately 600 meters, at a very low light level and a very cold temperature (4.8 C ). The collection chamber (the cod end) is light proof and insulated and is closed prior to being brought back to the surface. Any light will blind, and warm water exposure will "fry", (denature the proteins essential for life) the organisms before they get onboard. Once onboard, the cod end is taken to a cold room where it is opened and the organisms inside sorted out and prepared for experiments under dim red light. I am always in anticipation of the recovery of the cod-end. The trawl nets capture not only the organisms of interest to Dr. Frank and Dr. Cohen, but also a variety of other organisms found in the mesopelagic zone. These include organisms of almost every phylum and class of our biological world. This biological diversity is what brings the other scientists on board. 
Dr. Brad Seibel has an intense interest in cephalopods (squids, octopus and cuttlefish). I am in awe of his knowledge of cephalopods. Some of the cephalopods recovered in the nets include glass squids, Leachia dislocata , vampire squids Vampyroteuthis ufernalis, as well as octopus hatchlings. I always knew that cephalopods independently evolved excellent vision and an eye structure similar to that as humans. There are differences though. I was amazed by his demonstration on how an octopus changes the focal point of its lens by hydrostatic fluid changes in its eye, which is different from humans. Bringing preserved specimens of octopus back to my classroom and demonstrating the similarities and differences in the eye of a cephalopod vs. human eye, is a powerful tool when teaching convergent evolution. Dr. Seibel is interested in measuring the metabolic rate of cephalopods. Videotape of Dr. Seibel measuring the metabolic rates of cephalopods provides a wonderful real life parallel for my AP Biology students. My biology students perform an experiment in which they measure the metabolic rates of germinating peas. Thus I anticipate a strong real-world connection and comprehension for my students when they view video clips of Dr. Seibel's experiments prior to performing their metabolic experiments next school year. Dr. Will Jaeckle and Dr. Susie Balser, as well as an undergraduate Amy Slott, are studying the planktonic larvae forms of marine organisms found in this pelagic region. I am in awe in that they have identified and photographed over twenty different phyla of thus far. They are interested to see if larvae are undergoing asexual budding during their larvae stages, which is a new and amazing concept for me. The larval forms of marine organisms have always fascinated me. Viewing them under the microscope as well as observing their photographs has made me more prolific in larvae identification. Next year when I do plankton tows in my marine science classes, my student's fascination and identification of planktonic larvae will be greatly enhanced from the knowledge I gained from them. 
Dr. Megan Porter is studying the molecular biology behind an organism's ability to detect different
wavelengths of light. As mentioned earlier, larval and juvenile forms of deep-sea organisms live
at different depths, and therefore may detect light at different frequencies than adults.
The proteins (opsin proteins) in photoreceptor cells have to change at different stages of their
lives in order for them to be able to do so. This is controlled by genes expressing different DNA
sequences. Dr. Porter is collecting photoreceptor tissue samples of various deep-sea shrimp during
various life stages, and will determine the DNA and RNA sequences of the opsin genes (and thus protein
expression) during those life stages. A major concept and a very difficult concept to teach high
school students is the biological transcription and translation process from genes to proteins.
To have this real life example to teach this very difficult concept to high school students will make
me a more effective teacher on this concept.
Onboard are also undergraduate and graduate students. It is fascinating to see these young budding scientists and the enthusiasm they posses for the marine environment and science. Scientifically their lives are an open book, ready to be filled with approaching science careers. What a fantastic opportunity to them to see and experience scientific exploration. I am sure some of them are thinking of topics for their theses and dissertations based on the research going on in this ship. Also onboard are independent filmmakers. These are people who produce the scientific documentary films which most of us including my students see. Absolutely fascinating to see the techniques they use to bring us the findings of science to the general public. 
The scientists on board New Horizon consist of only about 1/3 of the people onboard this vessel.
A lesson I want to bring back to my students is that you don't have to have a PhD to be part of
a scientific research cruise. Assisting the scientists with their experiments are science technicians,
as well as the ship's captain and crew and engineers. All have different levels of education and training
and all play an essential role in the success of the scientific mission and proper operation of the ship.
A unique benefit of being a technician, or part of the ship's crew, is you get to travel where the ship
travels. Members of the ships crew have been to hydrothermal vents, seen erupting underwater volcanoes,
and been to ports in Mexico, Brazil and Japan. As a high school teacher of students of all abilities and
interests, I am hoping students who love the ocean and to travel, when seeing the photos and video footage
from this voyage, will be motivated to become interested in being part of an ocean going research cruise.
I would like to thank Dr. Frank, the National Science Foundation, and the St. Lucie County School system for making it possible for me to participate on this research cruise. Prior to this cruise, the mesopelagic region of the ocean was just a concept in a textbook I taught to my students. The mesopelagic ocean is now part of my life experiences. The memories will last my lifetime, the lessons I will teach will be passed on to future generations, and the photos and preserved specimens I bring back will last forever. 
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