BOZEMAN – After 5 ½ weeks at sea, a Montana State University graduate student is back in the lab examining microbial life in 3-million-year-old sediments pulled from underneath the ocean floor.
No longer eating saltine crackers to prevent seasickness, Max Amenabar is starting to analyze the contents of 1,000 glass vials to better understand the extent of microbial life in sediments collected from the bottom of the North Atlantic Ocean. He expects the job will keep him and two undergraduate students busy for the next 2 ½ years while he earns his doctorate in MSU’s Department of Microbiology and Immunology.
Amenabar was part of a team of scientists that sailed on the final scientific voyage of the R/V Knorr, Cruise KN223. The ship is best known for carrying researchers to the sunken Titanic in 1985.
On its most recent expedition, the Knorr transported its passengers to the western North Atlantic Ocean where they took geochemical measurements and gathered ancient sediments and nearby seawater. The scientists are now analyzing their samples to learn more about the bottom water chemistry during the Last Glacial Maximum when ice sheets were at their most recent maximum extension and covered much of North America, northern Europe and Asia. The ice sheets had a major impact on the Earth’s climate, causing drought and a dramatic drop in sea levels.
The overarching goal of the expedition was to determine circulation patterns in oceans during the Last Glacial Maximum about 20,000 years ago and compare them to present day patterns, said Amenabar’s adviser and MSU microbiologist Eric Boyd.
“The improved understanding of the relationship between circulation patterns in the Atlantic and climate is societally important, because future changes in these circulation patterns are likely to have very substantial effects, such as changes in the climate of northwest Europe and the ability for oceans to take up carbon dioxide,” Boyd said.
Because of previous projects, Amenabar was used to microbes that grow in the extremes of Antarctica and Yellowstone National Park, but not in the depths of the ocean. Commenting on the Knorr expedition, he said, “It was a really nice experience for me. I learned a lot.”
A native of Santiago, Chile, Amenabar was one of four microbiologists and 20-some scientists on the expedition that was funded by the National Science Foundation and organized by professor Steven D’Hondt at the University of Rhode Island.
The expedition left Oct. 26 from Woods Hole, Mass., and returned there Dec. 3. To make the most of their time at sea, the scientists generally worked 12-hour shifts with Amenabar’s shift running from noon to midnight. Among other things, he processed cores that were more than 130 feet long and had traveled through water as deep as three miles to reach the Knorr. Once the cores arrived on deck, the curation team cut them into more manageable pieces using sterile equipment and techniques. Amenabar placed some sediments into sterile vials for use in growing the organisms. He placed other sediments on dry ice to preserve their genetic material.
“Long cores, long days” was a saying on the ship, and it proved true, said Amenabar, who had to fit Thanksgiving dinner around his work schedule. Occasionally, he had time for recreation, but he spent much of his spare time in his unofficial role as one of the expedition’s photographers.
“Virtually all the work done on board and after the cruise ends up complementing each other,” said Richard Murray, chief scientist on the expedition, professor in the Department of Earth and Environment at Boston University and now temporary director of the NSF’s Division of Ocean Sciences.
“In Max’s case, a lot of the shipboard work on the chemistry of the pore water (the water in the sediment that is between the sedimentary grains) will really help us understand the environment ‘his’ microbes live in,” Murray said. “Conversely, his work on the type of microbes, how active they are, and so on, will greatly assist us as we try to figure out how the ocean has worked in the past.”
Murray said Amenabar’s job was crucial to the mission, and he did it well.
“The key thing is that we were not doing any microbiology analyses on the boat, so it was very critical that Max and the other microbiologists properly stabilize the samples so that they would be preserved for shore-based work,” Murray said. “It is delicate work to do and has to be done correctly as we just can’t very well run out there again and re-grab them.”
Boyd, Amenabar’s adviser, said the opportunity for Amenabar to join the expedition arose last spring when D’Hondt, a professor of oceanography at the University of Rhode Island, came to Bozeman to speak at a seminar sponsored by MSU’s Thermal Biology Institute. Amenabar took D’Hondt to breakfast, and the two became acquainted. After learning of Amenabar’s interests and skills, D’Hondt invited Amenabar to join his team on the Knorr. D’Hondt said he organizes these kinds of expeditions every couple of years with the purpose of understanding microbial life beneath the sea floor.
“Max and Eric have tremendous skills in the study of microorganisms that we don’t have, so it’s a great opportunity to collaborate,” D’Hondt said.
Amenabar said the expedition gave him a research experience he will never forget. Not only did it give him plenty of samples for his graduate work, but it allowed him to work with an “awesome” group of scientists, which may lead to future collaborations. He gained new skills in oceanography and learned that he can work with a variety of personalities under extreme conditions – a necessary skill when confined to a ship, he noted.
MSU undergraduate students benefited, too, Amenabar said. Besides helping analyze the samples, the undergraduates will have the opportunity to present their findings in talks, posters and undergraduate theses. Before the expedition began, they helped prepare the 1,000 glass vials that Amenabar filled on the Knorr.
Explaining, Boyd said, "They had to prepare the media following strict protocols much like a baker has to follow a recipe or the bread won’t turn out. They made nine different medium formulations and, in doing so, learned the difficult process of how to make medium oxygen free.”
The expedition was a collaboration among several U.S. institutions and involved colleagues from Japan. According to the chief scientist, the international nature of the expedition was another plus.
“That we all get to work with folks with different national backgrounds and of different ages is terrific for the students as well as the senior researchers like myself,” Murray said. “One of the great things about oceanography is the opportunity to be on a ship with a diverse suite of individuals as we collectively focus on a common topic, or at least a common region, and all interact together.”
Evelyn Boswell, (406) 994-5135 or firstname.lastname@example.org