Lilian Vaughan Morgan
|Lilian Vaughan Morgan|
|Born||Lilian Vaughan Sampson
July 7, 1870
|Died||December 6, 1952
Los Angeles, California
|Other names||Lilian Vaughan Sampson|
|Institutions||Bryn Mawr College
California Institute of Technology
|Alma mater||Bryn Mawr (B.S.), Bryn Mawr (M.S.)|
|Known for||Discovery of attached-X chromosomes, discovery of ring chromosomes|
Lilian Vaughan Morgan (née Sampson; July 7, 1870 – December 6, 1952) was an American experimental biologist who made seminal contributions to the genetics of Drosophila melanogaster. Morgan began her research in anatomy and development, and moved to Drosophila genetics after marrying Thomas Hunt Morgan and a long career break raising their children. While always being committed to her family, she published 16 single author papers in her lifetime, and made major contributions to the basic toolkit that makes Drosophila melanogaster one of the most powerful model systems in biology. In addition to her research career, she was involved in science education and was one of the founders of the Children's School of Science in Woods Hole, MA.
Lilian Vaughan Sampson was born in 1870 in Hallowell, Maine. She was orphaned at the age of three when her parents and younger sister died of tuberculosis. After this, she was raised by maternal grandparents with her older sister Edith in Germantown, Pennsylvania.[disambiguation needed]
Early research career
Lilian Sampson enrolled as an undergraduate student at Bryn Mawr in 1887 and majored in Biology. In addition to biology she took a many course in mathematics, physics and chemistry and was advised by Martha Carey Thomas, a socially progressive educator who would go on to be president of Bryn Mawr. After her graduation with honors in 1891, she spent the summer at the Marine Biological Laboratory in Woods Hole, MA. Edmund Beecher Wilson, one of her Zoology professors at Bryn Mayr was her advisor at MBL and introduced her to Thomas H Morgan, her future graduate advisor and husband.
In the autumn of 1891, a European fellowship for the best graduate in class enabled her to go to Europe and study muscles in chitons at the University Zurich with Arnold Lang, a comparative anatomist and student of Ernst Haeckel’s. She returned to Bryn Mayr in 1892 and received her MS in biology in 1894, under supervision of Thomas H. Morgan. After graduation, she published her work on the musculature of chitons and returned to Woods Hole as an independent investigator, where she spent a total of 7 summers in the 1890s investigating breeding, development and embryology in amphibia.
In 1904, at the age of 34, she married Thomas Hunt Morgan, and moved to New York City where he had taken a position at Columbia University. That following summer in 1905 they went to California where her husband received a teaching post and Lilian worked at the Stanford Marine Laboratory on planarian regeneration. Her work on planarian regeneration published in 1905-6 would be the last papers she would publish for another 16 years. During this time she raised four children (Howard Key Morgan, born 1906; Edith Sampson Morgan, born 1907; Lilian Vaughan Morgan, born 1910; Isabella Merrick Morgan, born 1911) and supported her husband's career. Shine and Wrobel (1976) note that one key to Thomas Hunt Morgan's success was that his personal affairs were entirely handled by Lilian Morgan, freeing him to focus on his research. The family spent their winters in New York and returned in the summers to Woods Hole, where she maintained a summer house for children, relatives and her husband's graduate students. This summer house would remain operational for many years and her grandchildren would visit at one point and find it ready for science lessons for children.
Involvement in science education
Together with several other women, she founded in 1913 the “Summer School Club” at Woods Hole, which is now the Children's School of Science in Massachusetts. The emphasis of the summer club soon became science education and Lilian Morgan was the first educational chairperson and became the Science Committee Chair in 1914. She preferred working outdoors with children to conduct experiments, and discuss problems and collections made by the pupils. She invited children to study without pressuring them to engage.
Later research career
When her own children were old enough, Lilian Morgan considered studying the violin or returning to the laboratory – she decided for the latter, and became a Drosophila geneticist – despite her husband who made it clear to her that she would be on her own, as an independent investigator. She was given working space at Columbia University in the laboratory of her husband, she maintained her own Drosophila stocks, worked independently, she was welcome, but had no official appointment. As the wife of the head of the laboratory who was not entirely comfortable with her presence, she was in a difficult position as she never became a part of the “inner circle” of the scientists. The atmosphere of the lab was “a little that of an exclusive men’s club” and Lilian Morgan may have felt particularly isolated because she was older than the other women (according to Jack Schultz a graduate student at that time), also she was not an outgoing person or talkative (according to Alfred Sturtevant. However, when she talked, she knew what she meant to say and she freely discussed her work with other geneticists. Yet, because she didn't hold a professional status, she never attended a scientific meeting and thus never presented a paper at a conference.
Major research accomplishments
Lilian Morgan was the original discoverer of the attached-X and ring chromosomes in Drosophila melanogaster. The normal Drosophila X-chromosome is telocentric, i.e. the centromere is located on one end of the chromosome. An attached-X chromosome is produced when two X-chromosomes share one centromere. Such an event produces a compound of two X chromosomes, which is transmitted as a single entity exclusively from mother to daughter. Lilian Morgan's original attached-X chromosome strain has been invaluable for Drosophila genetics, since it allows mutant alleles on a different X chromosome to be maintained clonally in a stock only in males, which do not undergo recombination.
Lilan Morgan's second major contribution to the Drosophila genetic toolkit was the discovery of ring chromosomes. Ring chromosomes were discovered based on unusual frequencies of recombination in an attached-X stock that revealed a circularized X-chromosome on cytological examination. Ring-X chromosomes are unstable in early development, a phenomenon that has been applied to generate mosaic tissues containing XX and XO cells during mitosis that bear recessive loss-of-function alleles of specific X-linked genes.
Lilian Morgan and her family moved to California in 1928 and she continued her Drosophila research at the California Institute of Technology in Pasedana where her husband Thomas Hunt Morgan became the division head. In 1946 her husband passed away, and one year afterwards, Lilian Morgan, at the age of 76, would finally get her first official appointment of her life as a Research Associate. She died in 1952 at the age of 82 in Los Angeles.
List of Publications
- Sampson, L. V. 1894. Die Muskulatur von Chiton. Jenaischen Zeitschrift fuer Naturwissenschaft 28: 460-468.
- Sampson, L. V. 1895. The musculature of chiton. J. Morphology 11:595-628.
- Sampson, L. V. 1900. Unusual modes of breeding and development among anura. Amer. Naturalist 34:687-715.
- Sampson, L. V. 1904. A contribution to the embryology of Hylodes martinicensis. Araer. J. Anat. 3: 473-504.
- Morgan, L. V. 1905. Incomplete anterior regeneration in the absence of the brain in Leploplana litloralis. Biol. Bull. 9:187-193.
- Morgan, L. V. 1906. Regeneration of grafted pieces of planarians. J. Exp. Zool. 3:269-294.
- Morgan, L. V. 1922. Non-criss-cross inheritance in Drosophila melanogaster. Biol. Bull. 42:267-274.
- Morgan, L. V. 1925. Polyploidy in Drosophila melanogaster with two attached X chromosomes" Genetics 10:148-178.
- Morgan, L. V. 1926. Correlation between shape and behavior of a chromosome" Proc. Natl. Acad. Sci 12:180-181.
- Morgan, L. V. 1929. Composites of Drosophila melanogaster. Carnegie Inst. of Wash. Publ. No. 399: 225-296.
- Morgan, L. V. 1931. Proof that bar changes to notbar by unequal crossing-over" Proc. Natl. Acad. Sci 17:270-272.
- Morgan, L. V. 1933. A closed X chromosome in Drosophila melanogaster" Genetics 18:250-283.
- Morgan, L. V. 1938a. Origin of attached-X chromosomes in Drosophila melanogaster and the occurrence of non-disjunction of X's in the male. Amer. Naturalist 72:434-446.
- Morgan, L. V. 19386. Effects of a compound duplication of the X chromosome of Drosophila melanogaster" Genetics 23:423-462.
- Morgan, L. V. 1939. A spontaneous somatic exchange between non-homologous chromosomes in Drosophila melanogaster" Genetics 24:747-752.
- Morgan, L. V. 1947. A variable phenotype associated with the fourth chromosome of Drosophila melanogaster and affected by heterochromatin" Genetics 32:200-219.
- Morgan, T. H., H. Redfield, and L. V. Morgan. 1943. Maintenance of a Drosophila stock center, in connection with investigations on the germinal material in relation to heredity. Carnegie Inst. Wash. Yearbk. 42:171-174.
- Morgan, T. H., A. H. Sturtevant, and L. V. Morgan. 1945. Maintenance of a Drosophila stock center, in connection with investigations on the germinal material in relation to heredity. Carnegie Inst. Wash. Yearbk. 44:157-160.
- Keenan, Katherine (1983). "Lilian Vaughan Morgan (1870-1952): Her life and Work". Amer. Zool. 23: 867–876. doi:10.1093/icb/23.4.867.
- Shine, Ian; Beadle, Sylvia Wrobel ; foreword by George W. Beadle (1976). Thomas Hunt Morgan : pioneer of genetics (Paperback ed. ed.). Lexington, Ky.: University Press of Kentucky. ISBN 978-0-8131-9337-3.
- Morgan, L.V. (1922). "Non-criss-cross inheritance in Drosophila melanogaster". Biol. Bull. 42: 267–274. doi:10.2307/1536473.
- Morgan, LV (March 1926). "Correlation between Shape and Behavior of a Chromosome.". Proceedings of the National Academy of Sciences of the United States of America 12 (3): 180–1. doi:10.1073/pnas.12.3.180. PMC 1084483. PMID 16576974.