C ampus n ews Monday, September 22, 2008
Introducing invasive plant life? You’re in luck By Christopher Baker Contributing Writer
In a recent study, a Brown researcher and a colleague have challenged the conventional understanding of the dangers of introducing new species to existing ecosystems. The study, published in the Proceedings of the National Academy of Sciences by Dov Sax, assistant professor of biology, and Steven Gaines, a professor at the University of California, Santa Barbara, found that invasive plant species have rarely caused the extinction of native plant species on islands. Sax said this discovery was unexpected because the introduction of exotic birds and other terrestrial vertebrates to islands frequently leads to extinction of native species. Additionally, on the islands the scientists examined in their study, more exotic plant species are becoming naturalized over time, and this process shows no signs of slowing. As a result, biodiversity in these areas is steadily increasing. Furthermore, the results of the study have helped further scien-
tists’ understanding of what causes extinctions, allowing them to better avoid these future events. The study suggests that invasive terrestrial vertebrates are more threatening to native species than invasive plants because vertebrates are more likely to be predators. In cases involving the introduction of exotic terrestrial vertebrates, “the combined influence of predation acting alone and predation acting in concert with other factors is believed to account for 98 percent of all extinctions,” says the study. The competition between exotic and native plants does not usually lead to immediate extinctions, so exotic plants are able to gradually become a part of the islands’ biodiversity. “The number of new exotic species is just going up every year,” said Sax. “That’s surprising because the expectation would be that the number should be starting to level off at some point if these islands are filling up with species. And so there’s just no evidence that these islands are filling up. There seems to be room for more and more species to be added.”
The findings offer a better understanding of conservation strategies such as assisted migration, in which a threatened species is relocated to a more advantageous location. “On some level, my work suggests, on islands –– if that can be generalized –– is that you could probably move plants without causing other plants to go extinct,” Sax said. But there are still concerns that invasive plants might contribute to the long-term extinction of native plant species. According to Sax, some native species might be experiencing what is called “extinction debt”. “What’s really the next level is figuring out how extinction debt works,” said Sax, who hopes that his research will address the possibility of long-term extinctions that are not immediately apparent. For the time being, scientists like Sax choose to err on the side of caution. Until more is known about extinction debt, “you probably wouldn’t want to move plants around,” said Sax, whose next research project will investigate the phenomenon.
Students interpreting for local hospital patients By Sydney Ember Contributing Writer
Student volunteers in the Brown Interpreter’s Aide Program are breaking down linguistic barriers at Rhode Island Hospital. Student interpreters in the program help doctors and non-English speaking patients at the hospital communicate, in the process gaining medical experience and learning professional terminology. Students in the program, which is run jointly by the Alpert Medical School and R.I. Hospital, work weekly four-hour shifts at the hospital throughout the year. The program’s interpreters allow non-English speaking patients to “express what they are really feeling,” said Zoila Quezada, manager of minority medical affairs at the Med School. Because non-English speakers constitute a growing percentage of the U.S. population, the need for interpreter ser vices continues to increase at Providence hospitals, said Martha Aktchian, manager of interpreter services at R.I. Hospital. Many of the interpreters work with locals who speak Spanish or Portuguese. The program stresses the importance of language proficiency, targeting bilingual freshmen fluent in those languages. According to Laura Mainardi Villarino ’10, one of the program’s coordinators, many of these bilingual students know what it feels like not to be able to communicate with doctors based on their parents’ experiences. Though many students involved in the program are premed, she stressed that most participants are drawn to the program because they want to volunteer in the Spanish-speaking community. “It’s a program for bilingual students who want to help,” Mainardi Villarino said. “People go in for the right reasons.” Given the program’s relatively small size — five undergraduate students participated last year — recruitment ef for ts, especially
Page 5
THE BROWN DAILY HERALD
among current medical students, have increased. The leaders of the program are hoping to boost its membership to 10 or 15 volunteers this year. Thirty-five students attended a recent info session for the program, but the time-intensive training process and the time commitment required discourage many students other wise interested in the program. Before students can become interpreter’s aides, they must take a language exam focused on medical terminology and other standard vocabulary, then undergo training. Nermarie Velazquez ’10, the other coordinator of the program, said it was important to test for proficiency because members “need to be fluent, need to be comfortable.” Students then spend 16 hours shadowing a professional interpreter at the hospital. Most participants
who join at the beginning of the academic year are able to interpret by themselves by December. Because doctors treat interpreter’s aides as hospital employees, the experience is “really interesting if you’re pre-med,” Velazquez said. “Being part of something like this, you see the end result of where you want to be.” Many students also find that the program helps their ability to communicate and understand different dialects, an important skill for future doctors, who will have to navigate an increasingly multilingual society. “Ever y countr y has its own brand of Spanish,” said Velazquez, a native of Puerto Rico. She remembered struggling to understand a mother from Guatemala who was telling the doctor her daughter would not drink formula, a word continued on page 6
Ne
ws
i n
B
r i e f
‘Microbe hunter’ honored with Lasker Brown alum and microbiologist Stanley Falkow PhD’61 will receive the Lasker-Koshland Achievement Award in Medical Science on Sept. 26 for his advances in identifying how the smallest organisms function. Falkow told The Herald he first became interested in microbiology when he was 11 years old. He was given a copy of “Microbe Hunters,” a book based on the lives of Louis Pasteur and Robert Koch. Falkow said he remembers being “fascinated” by the book and knew then that he wanted to devote his life to studying microorganisms. The Lasker Foundation, according to its Web site, is now recognizing Falkow as “one of the great microbe hunters of all time.” He developed a method of examining how bacteria pass certain traits on to each other using recombinant DNA technology and pioneered the use of fluorescent imaging to track microorganisms inside host cells. He also established the existence of plasmids and proved that they were pieces of DNA outside the chromosomes. In 1976, Falkow and one of his students were able to isolate the toxin gene from a strain of diarrhea-causing E. coli, in a sense cloning the first gene related to bacteria transmission. His methods and discoveries revolutionized the way scientists study the spread of bacteria and he played a major role in discovering and understanding the causative agents of diseases like tuberculosis, whooping cough and certain sexually transmitted diseases. Despite his extensive list of laboratory-related accomplishments, Falkow, who is a professor of microbiology at Stanford University School of Medicine, said that teaching is one of the most important parts of his life. “A pleasing part of the award is that it talked about teaching,” he said. “Professors learn more from their students than their students learn from them.” According to the Lasker Foundation’s Web site, the award is given to scientists “whose professional careers have engendered within the biomedical community the deepest feelings of awe and respect.” The Lasker Foundation was established to honor the work of Mary Woodard Lasker, a medical research activist. The award, which includes a $300,000 prize, will be presented at a ceremony in New York City. Falkow still remembers the influence his own teachers had on his career. “The Biology Department at the time was really supportive of me and what I did. I was quite lucky in that sense.” Falkow admits that he “worked pretty hard” at Brown, but also recalls meeting Seymour Lederberg, professor emeritus of medical science, when they were both students together. He and Lederberg, whom he cites a source of personal inspiration, used to sit in a drugstore on Thayer, drinking fountain sodas and discussing their lab work. “Being a student is the best point of your life. You have no responsibilities besides learning,” Falkow said. Falkow said he was “lucky enough to have (his) dream come true.” For students pursuing their dreams today, he has two pieces of advice: “Follow your heart and take advice from someone who can give you wise council.” He added, however, “It’s important not to try to please others. You have to ask them what they want and you have to do what you want.” — Anne Speyer