Only half an hour from the Hamilton College campus, near Fayetteville, N.Y., there is a rare biological spectacle lying hidden from casual eyes. Green Lake is one of the few meromitic lakes in the world. The term "meromitic" refers to that while most lakes have constant water cycling (water that was at the top of the lake one week could be at the bottom the next) Green Lake has virtually none, leading to portions of water that have been on the bottom of the lake for hundreds of years. For practical purposes, such as swimming or boating, the distinction makes little difference but Greg Ray '08 (Pittsburgh, Pa.) and Tara Apo '10 (Maui, HI) and their research advisors Professor of Biology Jinnie Garrett and Assistant Professor of Biology Michael McCormick aren't there to swim. Instead, the team is working to gain new insights into the levels, patterns, and characteristics of diversity in one of the world's most unique and understudied ecosystems.
Ray explains that since there is almost no water circulation in Green Lake, the top layer, or stratum, is full of aerobic organisms that use oxygen to oxidize their food and perform other vital processes. "Every living thing needs a method of oxidizing its food to get energy from it, and oxygen is the most efficient mechanism," he says. Apo points out that the top stratum is, "very much like what you would see in a normal lake." The depth of the top stratum, the team clarifies, varies depending on the amount of wind, outside water interference such as streams and rain, and sunlight the lake receives. At the bottom of Green Lake and other meromitic lakes, though, there's a completely different story.
Ray explains that other chemical elements with similar properties to oxygen can also oxidize food. "The bottom stratum," he informs me, "will be – we believe – much more diverse than the upper stratum, since there are many oxidation methods used in the bottom stratum, but in the top there's mainly the oxygen pathway." Even Green Lake has some overlap between its strata, and this area – no more than 10 feet thick – between the extreme strata is known as the chemocline. It's there that Apo and Ray expect to find the most diversity of all. "In the chemocline, you have organisms that use oxygen, organisms that use other pathways, and organisms that live only in the chemocline all together," enthuses Apo. "That's what makes it a great place to take most of our samples from.
The group takes samples of the water from their perch on a boat – not your average fishing trip. Back at the lab, the team purifies the water from the inorganic material, such as sticks and dirt, brought up with the samples. Then, different categories of organisms are isolated by the process of amplification, in which one type of organism is made to reproduce to the point of taking over the other types. Then, the different members of the category are separated, and the group sequences the DNA of each organism to determine its identity. The group is comparing its results to a similar study of Green Lake run in the 1950s, which showed low levels of diversity. Ray and Apo believe the modern study will show a different – and much greater – variety of organisms. Ray justifies the hypothesis by pointing out that the technology for isolating and identifying organisms is far superior today to what was available in the 1950s. "We're using methods they couldn't have dreamed of," he says. "I'm honored to have the opportunity to work in the modern age." The group hypothesizes that, instead, their results will much more closely mimic those of studies done on other meromitic lakes in the recent past.
Ray intends on receiving a concentration in biochemistry and an environmental studies minor when he graduates next May. He wants to pursue a graduate degree after Hamilton and has a particular passion for unicellular organisms. During the year, Ray can be found all over campus, depending on the time of day. He serves as a class representative on the Student Assembly, an Orientation Leader, a Writing Center tutor, a Teaching Assistant (TA) for chemistry courses, a tour guide, the treasurer of the Hamilton chapter of the American Chemical Society (ACS), and president of the Four Square Club. He is also an enthusiastic Pittsburgh Steelers fan. Ray and Apo met in Biology 248 – Genes and Genomes – a class taught by Garrett they both took this spring. Apo is also considering a concentration in biochemistry and a minor in environmental studies, and wants to continue doing research, saying it has been her passion, "since I was in high school." During the academic year, Apo is a TA in various biology classes, a member of the BioMatters Club, and a writer for the Science and Technology section of Hamilton's student newspaper, the Spectator.
-- by Elijah Lachance '10
Ray explains that since there is almost no water circulation in Green Lake, the top layer, or stratum, is full of aerobic organisms that use oxygen to oxidize their food and perform other vital processes. "Every living thing needs a method of oxidizing its food to get energy from it, and oxygen is the most efficient mechanism," he says. Apo points out that the top stratum is, "very much like what you would see in a normal lake." The depth of the top stratum, the team clarifies, varies depending on the amount of wind, outside water interference such as streams and rain, and sunlight the lake receives. At the bottom of Green Lake and other meromitic lakes, though, there's a completely different story.
Ray explains that other chemical elements with similar properties to oxygen can also oxidize food. "The bottom stratum," he informs me, "will be – we believe – much more diverse than the upper stratum, since there are many oxidation methods used in the bottom stratum, but in the top there's mainly the oxygen pathway." Even Green Lake has some overlap between its strata, and this area – no more than 10 feet thick – between the extreme strata is known as the chemocline. It's there that Apo and Ray expect to find the most diversity of all. "In the chemocline, you have organisms that use oxygen, organisms that use other pathways, and organisms that live only in the chemocline all together," enthuses Apo. "That's what makes it a great place to take most of our samples from.
The group takes samples of the water from their perch on a boat – not your average fishing trip. Back at the lab, the team purifies the water from the inorganic material, such as sticks and dirt, brought up with the samples. Then, different categories of organisms are isolated by the process of amplification, in which one type of organism is made to reproduce to the point of taking over the other types. Then, the different members of the category are separated, and the group sequences the DNA of each organism to determine its identity. The group is comparing its results to a similar study of Green Lake run in the 1950s, which showed low levels of diversity. Ray and Apo believe the modern study will show a different – and much greater – variety of organisms. Ray justifies the hypothesis by pointing out that the technology for isolating and identifying organisms is far superior today to what was available in the 1950s. "We're using methods they couldn't have dreamed of," he says. "I'm honored to have the opportunity to work in the modern age." The group hypothesizes that, instead, their results will much more closely mimic those of studies done on other meromitic lakes in the recent past.
Ray intends on receiving a concentration in biochemistry and an environmental studies minor when he graduates next May. He wants to pursue a graduate degree after Hamilton and has a particular passion for unicellular organisms. During the year, Ray can be found all over campus, depending on the time of day. He serves as a class representative on the Student Assembly, an Orientation Leader, a Writing Center tutor, a Teaching Assistant (TA) for chemistry courses, a tour guide, the treasurer of the Hamilton chapter of the American Chemical Society (ACS), and president of the Four Square Club. He is also an enthusiastic Pittsburgh Steelers fan. Ray and Apo met in Biology 248 – Genes and Genomes – a class taught by Garrett they both took this spring. Apo is also considering a concentration in biochemistry and a minor in environmental studies, and wants to continue doing research, saying it has been her passion, "since I was in high school." During the academic year, Apo is a TA in various biology classes, a member of the BioMatters Club, and a writer for the Science and Technology section of Hamilton's student newspaper, the Spectator.
-- by Elijah Lachance '10
