When most people think of turtles, they think of walking shields, animals that take their homes with them wherever they go. Certainly, the word "vulnerable" doesn't come to mind. Nevertheless, turtles are reptiles, one of the two classes of animals most affected by global environmental change (the other is amphibians.) Jillian Berkowitz (Cranford, N.J.), Kristen Selden (Southborough, Mass.) and Amy Klegarth (Germansville, Pa.), three members of Hamilton's Class of 2009 under the advisement of Professor of Biology David Gapp and with the assistance of the Director of the Hamilton Microscopy and Imaging Facility Ken Bart, are realizing they don't have to travel too far to see the impact and make a difference. The team's research on the digestive tract of the painted turtle could shed much-needed light on how, and how many, toxins in the air and water make it into the bloodstream of these truly defenseless and extraordinary animals.
"A painted turtle has a lifespan between 30 and 40 years, about," says Klegarth. It's obvious watching the team they're learning more than just data-points and conversational factoids. They carefully discuss how to handle the animals for a photograph, and show a respect for the animals that goes far beyond that given a simple biological specimen. "Turtles have been respected by many cultures, and I hope we're learning some of that," says Berkowitz. The natural beauty of the turtles is obvious even to the first-time viewer. The hard black bodies are both graceful and adorable at once, and the red striping on the feet and yellow marks on the head look distinguished and powerful, reminding me of the logos on a racecar. Nevertheless, the turtles don't move that fast. "They swim faster than they move on land," says Selden. "They're swimming turtles, which makes them rather rare."
Despite the glistening exteriors of the reptiles, it's what's inside the animals that primarily interests these scientists. "There were studies done in the 1950s that suggested the digestive tract in turtles was straight and simple," says Berkowitz. Now, however, the team intends to use much more advanced techniques to discover the true complexities of the reptilian digestion process. "We know now that there are different hormones secreted at some places in the digestive tract than others," says Klegarth. "Even the same hormones are produced at different levels in some parts of the tract," Selden points out. The team is also interested in the idea of cell differentiation – the idea that different types of cells have different functions within the tract and are in different locations – and folding along the tract. All in all, it's a very different picture from the one painted on the painted turtle in the 1950s.
The team plans to use a scanning electron microscope (SEM) to visualize the tract. The SEM works by shooting beams of electrons at a sample and can magnify its subject up to 350,000 times its original size, giving the team an unprecedented look at the possible cell differentiation. "We know the cell differentiation is there, the different hormone levels are there, that the folding is there, but we're the first to try to put it all together," says Selden. The team also plans on harvesting other organs from the turtles for possible future research. "Nothing will be wasted," Berkowitz assures me. Especially important is the possibility of finding a correlation between different hormone levels and either cell differentiation or tract folding. The team hopes to find details as to what kinds of processes and absorption takes place in the tract, leading to the possibility of seeing the effects of particular pollutants on the turtles and providing guidance on which chemicals to limit to ensure the turtles' survival. "Plus, we want to give the correct picture on what the digestive tract of the turtles looks like," says Klegarth. "The past research hasn't done that in a great deal of detail."
Klegarth, Selden, and Berkowitz all plan on pursuing Biology concentrations at Hamilton. Berkowitz plans to work for an Environmental Studies minor and become an environmental advocate or activist, while Klegarth plans an anthropology minor and a career in conservation biology, specifically the species conservation of large mammals. Selden is unsure about a minor, but wants to work on physiology, costal ecology, and marine biology. Selden is a hitter on the Hamilton varsity volleyball squad and runs hurdles for the track team, while Berkowitz is a defender in field hockey and Klegarth a captain of the equestrian team, as well as a resident advisor and a biology teaching assistant.
-- by Elijah Lachance '10
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| Painted Swimming Turtles |
Despite the glistening exteriors of the reptiles, it's what's inside the animals that primarily interests these scientists. "There were studies done in the 1950s that suggested the digestive tract in turtles was straight and simple," says Berkowitz. Now, however, the team intends to use much more advanced techniques to discover the true complexities of the reptilian digestion process. "We know now that there are different hormones secreted at some places in the digestive tract than others," says Klegarth. "Even the same hormones are produced at different levels in some parts of the tract," Selden points out. The team is also interested in the idea of cell differentiation – the idea that different types of cells have different functions within the tract and are in different locations – and folding along the tract. All in all, it's a very different picture from the one painted on the painted turtle in the 1950s.
The team plans to use a scanning electron microscope (SEM) to visualize the tract. The SEM works by shooting beams of electrons at a sample and can magnify its subject up to 350,000 times its original size, giving the team an unprecedented look at the possible cell differentiation. "We know the cell differentiation is there, the different hormone levels are there, that the folding is there, but we're the first to try to put it all together," says Selden. The team also plans on harvesting other organs from the turtles for possible future research. "Nothing will be wasted," Berkowitz assures me. Especially important is the possibility of finding a correlation between different hormone levels and either cell differentiation or tract folding. The team hopes to find details as to what kinds of processes and absorption takes place in the tract, leading to the possibility of seeing the effects of particular pollutants on the turtles and providing guidance on which chemicals to limit to ensure the turtles' survival. "Plus, we want to give the correct picture on what the digestive tract of the turtles looks like," says Klegarth. "The past research hasn't done that in a great deal of detail."
Klegarth, Selden, and Berkowitz all plan on pursuing Biology concentrations at Hamilton. Berkowitz plans to work for an Environmental Studies minor and become an environmental advocate or activist, while Klegarth plans an anthropology minor and a career in conservation biology, specifically the species conservation of large mammals. Selden is unsure about a minor, but wants to work on physiology, costal ecology, and marine biology. Selden is a hitter on the Hamilton varsity volleyball squad and runs hurdles for the track team, while Berkowitz is a defender in field hockey and Klegarth a captain of the equestrian team, as well as a resident advisor and a biology teaching assistant.
-- by Elijah Lachance '10
