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DUJS Fall 2003 Raymond Pearlʼs Legacy JILL HALTIGAN ʻ03 the Department of Biology at the Maine Agriculture The name Raymond Pearl resonates strongly with Experiment Station of the University of Maine in 1907. the scientific community. One of the most prolific There, his focus shifted to studying the genetics of poultry scientists of his day, he wrote about such diverse topics and other domestic animals, and he formulated ideas as population biology, disease, and Jewish and Christian which he subsequently applied to humans. Pearl used marriages in more than seven hundred and two articles Mendelian genetics to examine questions of eugenics and seventeen books over a span of forty-one years. He is and the effects of continued inbreeding and analyzed also remembered for his theories discussing longevity and individual and population growth using logarithmic arguing against eugenics, which were highly controversial curves. He recognized that progeny often lacked at the time. Although many of his conclusions have characteristics of their parents been disproved over years, and moved away from the one cannot ignore the classical eugenic research contributions Pearl made to position of focusing solely the scientific community. on individual couples. Raymond Pearl was Rather, Pearl studied born on June 3, 1879 in birth rate, death , and Farmington, NH, to Frank other population-level Pearl, a shoe factory foreman characteristics (American and grocery clerk, and Ida Philosophical Society). May McDuffee. Pearl enrolled From this research he at Dartmouth College at the published Diseases of Poultry age of sixteen intending to (1915) and Introduction study Greek and Latin. He to Medical Biometry and quickly changed his focus to Statistics (1923). The latter Biology, studying under John book became the authority H. Gerould. Upon graduating for all scientists working in 1899, he followed his new with qualitative data at the mentor, H. S. Jennings, to the time (Goldman 2002). University of Michigan. There As World War I began, Pearl’s he studied plant and animal interests again shifted, this variation and behavior. He time to food supply and also worked as an assistant the economics of food. He professor of zoology and image courtesy Dartmouth Library, of Rauner College was appointed by President collaborated on the Biological Raymond Pearl (1899) Herbert Hoover as Chief of Survey of the Great Lakes, the Statistical Division of researching the variation in native fishes. After receiving the US Food Administration, where he served from 1917- his Ph.D. in 1902 for his work on planarian behavior, Pearl 1919. While in Washington, Pearl published numerous traveled to Europe where he spent time at the University articles on nutrition and became increasingly fascinated of Leipzig and the Marine Biological Station in Naples. with human biological issues. In 1920, his administrative From 1905-1906, he worked in the Galton Laboratory work culminated with the publication of his fifth book, at the University College, London, investigating The Nation’s Food. statistical methods in biology with Karl Pearson. These During this time, Pearl also started his career as a years marked Pearl’s first attempts at using statistics to professor of Biometry and Vital Statistics in the new investigate population genetics. Pearl also became an School of Hygiene and Public Health at the Johns Hopkins associate editor of Biometrika, a position he held until University in nearby Baltimore, MD. He remained at 1910 when he resigned due to “professional differences” Hopkins until his death from coronary thrombosis in with Pearson (American Philosophical Society). 1940 at the age of sixty-one. He was survived by his Pearl returned to the United States in 1906 to wife Maude M. DeWitt, whom he married in 1903, and teach zoology at the University of Pennsylvania, their two daughters, Ruth DeWitt Jencks and Penelope remaining focused on biostatistics. He became head of Mackey. 22 DARTMOUTH UNDERGRADUATE JOURNAL OF SCIENCE SPRING 2003 23 Pearl’s years at Hopkins, where he also served as 1964, twenty-six years after Pearl convinced himself to professor of Biology and as statistician at the Johns quit smoking, did the United States Surgeon General Hopkins Hospital, were arguably his most prolific. Using warn the country of the negative effects of smoking a grant from the Rockefeller Foundation, he started the (Goldman 2002). Institute for Biological Research in 1925, allowing him Pearl’s illustrious career was well recognized during to apply his knowledge of statistics to human biology, his lifetime. He received numerous accolades including specifically to questions of human longevity. All of his honorary degrees from the University of Maine, research, including his studies with Drosophila, was Dartmouth College, St. John’s College, and Knight of the intended to shed light on these questions (American Crown of Italy. He was an honorary member of the Royal Philosophical Society). Pearl published The Biology of Society of Medicine and served as president of the America Death (1922), The Rate of Living(1928), and Alcohol Society of Zoologists, American Society of Naturalists, and Longevity (1926), which argued that moderate American Statistical Association, American Association consumption of alcoholic beverages could be beneficial of Physical Anthropologists, and the International Union to human health. for Scientific Investigation of Population Problems. He Pearl also further advanced population biology. Along was founder and editor of both the Quarterly Review of with Lowell J. Reed, Pearl theorized that the sigmoidal Biology (1926) and Human Biology (1929) and served as curve was a model of population growth, where expansion an associate editor for numerous other journals. is initially slow, but then raises exponentially until the Although not all of Pearl’s conclusions were carrying capacity of the environment is reached. Many substantiated by further scientific scrutiny, his novel of Pearl’s theoriessuch as this onewere very controversial, approach to combing statistics and biology to examine and his aggressive defense of them alienated many of numerous scientific questions was an important his contemporaries. Furthermore, he was adamantly contribution to the scientific community and cannot be opposed to eugenics, a very popular field at the time, overlooked. though he vocally supported various means of birth control (American Philosophical Society). REFERENCES: Perhaps his most famous study, carried out in 1938, concluded that smoking decreased longevity. Pearl “Glass Guide: Raymond Pearl,” American Philosophical Society followed 7,000 smokers over the age of thirty-five and (online) http://www.amphilsoc.org/library/guides/glass/pearl.htm. found that smokers consistently died at an earlier age than the non-smoker controls. His published results in Goldman, I. L. (2002). Raymond Pearl, Smoking and Longevity. Genetics 162: 997-1001. Science are the first “significant” data demonstrating that tobacco use has a negative effect on longevity. Not until Interested in science-writing or research? Being on staff is a great way to experience the process of pulling it all together on paper. There are multiple opportunities for writing, editing, or working on print layout. Blitz ʻDUJSʼ or come to our meetings on Thursdays at 9 PM, 212 Collis. 22 DARTMOUTH UNDERGRADUATE JOURNAL OF SCIENCE SPRING 2003 23.
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