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Harlan Lewis
Frank Harlan Lewis (January 8, 1919 – December 12, 2008) was an American botanist, geneticist, taxonomist, systematist, and evolutionist who worked primarily with plants in the genus Clarkia. He is best known for his theories of "catastrophic selection" and "saltational speciation", which are closely aligned with the concepts of quantum evolution and sympatric speciation. The concepts were first articulated in 1958 by Lewis and Peter H. Raven, and later refined in a 1962 paper by Lewis in which he coined the term "catastrophic selection". In 1966, he referred to the same mechanism as "saltational speciation".
Lewis was Dean of Life Sciences at the University of California, Los Angeles from 1962 to 1981, a Fellow of the American Association for the Advancement of Science (1955), recipient of a Guggenheim Fellowship (1955), president of the Pacific Division of the Botanical Society of America (1959), president of the Society for the Study of Evolution (1961), president of the American Society of Plant Taxonomists (1969), president of the International Organization of Plant Biosystematics (1969–1975), and president of the American Society of Naturalists (1971), as well as a Fellow of the California Academy of Sciences. In 2006, he became the Dickson Emeritus Professor of the Year at UCLA.
Lewis grew up on a ranch in Redlands, California, where his father grew apricots and oranges. His interest in plants dates at least from the age of 10 when his fifth grade teacher taught the class how to press flowers. His junior high and Redlands High School teachers continued to encourage his interest in plants. When he was in 10th grade he got permission to take a class in botany usually restricted to 11th and 12th graders. The teacher, Eva Maye Hyde, had been a student of Philip A. Munz; she also inducted him into the Samuel B. Parish Botanical Society, a group for amateur botanists in Southern California. He became president of the society in about 1939. During this time he attended a Botanical Society of America meeting, where he met Willis Linn Jepson.
Harlan Lewis graduated from Redlands High School in 1937, and got an A.A. degree in 1939 from San Bernardino Valley College.
He transferred to UCLA in 1939 as a junior. He started work with Carl Epling as an undergraduate, and published a paper with him in 1940 as the first author on the distributions of three species pairs in Californian chaparral and coastal sage plant communities. He continued with Epling as a graduate student, and got his M.A. in 1942 working on the genus Trichostema in the family Lamiaceae. His Ph.D. work concerned diploid and tetraploid Californian species of Delphinium. WWII interrupted his studies, and he completed his thesis in 1946.
Lewis became a faculty member at UCLA in that same year, 1946.
He joined the United States Army Air Corps at the start of WWII, working at Caltech with Frits Warmolt Went on camouflage.
Harlan Lewis' research interests were far ranging. They included taxonomy, cytogenetics, systematics, genetics, evolution, plant distributions, and even physiological ecology. And all of these manifested themselves before 1950. Indeed, as a young scientist he was involved with many research topics. His first publication was with Carl Epling in 1940 covered the distributions of three species pairs in Californian chaparral and coastal sage scrub communities. In this paper he shows his first interest in plant distributions as they relate to speciation. His next publications with Epling followed in 1942. One was taxonomic in nature, a continuing interest of his, and concerned itself with the genus Monarda in the Lamiaceae. His second paper in 1942 concerned itself with the distributions of the chaparral and coastal sage scrub communities in cis-montane California, and they concluded that these two communities had their centers of distribution in San Diego County, and probably entered the Southwestern United States from the North American Plateau. He also received his M.A. degree in 1942 on a completely different subject: the taxonomy of Trichostema in the Lamiaceae, which was published in 1945. As a result of his work with Frits Went at California Institute of Technology during the WWII years he published on yet a different subject: that of the response of 13 California annuals to photoperiod and temperature. Although they were not able to correlate the plant's response under artificial conditions to nature, they did discover that Madia elegans was inhibited in flowering by intermediate day lengths, and was induced to flowering by either short or long days, a rare condition known as ambiphotoperiodism. His PhD work in Delphinium was reported in an abstract in 1946, titled "Polyploidy in the Californian Delphiniums"; here he showed his first interest in the effects of ploidy on adaptation on three species that consisted of races that were diploid and tetraploid, and found that there were no morphological or ecological differences between the diploids and tetraploids. In 1947 he published on problems associated with using leaves for taxonomic purposes in Delphinium.
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Harlan Lewis
Frank Harlan Lewis (January 8, 1919 – December 12, 2008) was an American botanist, geneticist, taxonomist, systematist, and evolutionist who worked primarily with plants in the genus Clarkia. He is best known for his theories of "catastrophic selection" and "saltational speciation", which are closely aligned with the concepts of quantum evolution and sympatric speciation. The concepts were first articulated in 1958 by Lewis and Peter H. Raven, and later refined in a 1962 paper by Lewis in which he coined the term "catastrophic selection". In 1966, he referred to the same mechanism as "saltational speciation".
Lewis was Dean of Life Sciences at the University of California, Los Angeles from 1962 to 1981, a Fellow of the American Association for the Advancement of Science (1955), recipient of a Guggenheim Fellowship (1955), president of the Pacific Division of the Botanical Society of America (1959), president of the Society for the Study of Evolution (1961), president of the American Society of Plant Taxonomists (1969), president of the International Organization of Plant Biosystematics (1969–1975), and president of the American Society of Naturalists (1971), as well as a Fellow of the California Academy of Sciences. In 2006, he became the Dickson Emeritus Professor of the Year at UCLA.
Lewis grew up on a ranch in Redlands, California, where his father grew apricots and oranges. His interest in plants dates at least from the age of 10 when his fifth grade teacher taught the class how to press flowers. His junior high and Redlands High School teachers continued to encourage his interest in plants. When he was in 10th grade he got permission to take a class in botany usually restricted to 11th and 12th graders. The teacher, Eva Maye Hyde, had been a student of Philip A. Munz; she also inducted him into the Samuel B. Parish Botanical Society, a group for amateur botanists in Southern California. He became president of the society in about 1939. During this time he attended a Botanical Society of America meeting, where he met Willis Linn Jepson.
Harlan Lewis graduated from Redlands High School in 1937, and got an A.A. degree in 1939 from San Bernardino Valley College.
He transferred to UCLA in 1939 as a junior. He started work with Carl Epling as an undergraduate, and published a paper with him in 1940 as the first author on the distributions of three species pairs in Californian chaparral and coastal sage plant communities. He continued with Epling as a graduate student, and got his M.A. in 1942 working on the genus Trichostema in the family Lamiaceae. His Ph.D. work concerned diploid and tetraploid Californian species of Delphinium. WWII interrupted his studies, and he completed his thesis in 1946.
Lewis became a faculty member at UCLA in that same year, 1946.
He joined the United States Army Air Corps at the start of WWII, working at Caltech with Frits Warmolt Went on camouflage.
Harlan Lewis' research interests were far ranging. They included taxonomy, cytogenetics, systematics, genetics, evolution, plant distributions, and even physiological ecology. And all of these manifested themselves before 1950. Indeed, as a young scientist he was involved with many research topics. His first publication was with Carl Epling in 1940 covered the distributions of three species pairs in Californian chaparral and coastal sage scrub communities. In this paper he shows his first interest in plant distributions as they relate to speciation. His next publications with Epling followed in 1942. One was taxonomic in nature, a continuing interest of his, and concerned itself with the genus Monarda in the Lamiaceae. His second paper in 1942 concerned itself with the distributions of the chaparral and coastal sage scrub communities in cis-montane California, and they concluded that these two communities had their centers of distribution in San Diego County, and probably entered the Southwestern United States from the North American Plateau. He also received his M.A. degree in 1942 on a completely different subject: the taxonomy of Trichostema in the Lamiaceae, which was published in 1945. As a result of his work with Frits Went at California Institute of Technology during the WWII years he published on yet a different subject: that of the response of 13 California annuals to photoperiod and temperature. Although they were not able to correlate the plant's response under artificial conditions to nature, they did discover that Madia elegans was inhibited in flowering by intermediate day lengths, and was induced to flowering by either short or long days, a rare condition known as ambiphotoperiodism. His PhD work in Delphinium was reported in an abstract in 1946, titled "Polyploidy in the Californian Delphiniums"; here he showed his first interest in the effects of ploidy on adaptation on three species that consisted of races that were diploid and tetraploid, and found that there were no morphological or ecological differences between the diploids and tetraploids. In 1947 he published on problems associated with using leaves for taxonomic purposes in Delphinium.