Marcus Morton Rhoades (July 24, 1903 in

Graham, Missouri Graham is a city in Nodaway County, Missouri, United States. The population was 171 at the 2010 census. History Graham was originally called Jacksonville, and under the latter name was platted in 1856. The present name is after Col. Amos Gr ...

– December 30, 1991) was an American cytogeneticist.

Education

He earned a Bachelor of Science degree in 1927, a Master of Science degree in 1928 from the

University of Michigan , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

and a Ph.D. degree in 1932 from

Cornell University Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to ...

where he was a trainee of

Rollins A. Emerson Rollins Adams Emerson (May 5, 1873 – December 8, 1947) was an American geneticist who rediscovered the laws of inheritance established by Gregor Mendel. Early life Emerson was born on May 5, 1873, in tiny Pillar Point, New York, but at th ...

alongside future Nobel Prize winners

George Beadle George Wells Beadle (October 22, 1903 – June 9, 1989) was an American geneticist. In 1958 he shared one-half of the Nobel Prize in Physiology or Medicine with Edward Tatum for their discovery of the role of genes in regulating biochemical e ...

and

Barbara McClintock Barbara McClintock (June 16, 1902 – September 2, 1992) was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There ...

, and completed a thesis on the topic of cytoplasmic male sterility in maize.http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/rhoades-m-m.pdf

Career

After completing his doctoral studies, Rhoades's career spanned numerous institutions, first working as an experimentalist in plant breeding at Cornell University from 1932 to 1935, a research geneticist with the USDA in

Ames, Iowa Ames () is a city in Story County, Iowa, United States, located approximately north of Des Moines in central Iowa. It is best known as the home of Iowa State University (ISU), with leading agriculture, design, engineering, and veterinary med ...

and later Arlington, Virginia from 1935 to 1940, an associate professor and later full professor at

Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manha ...

from 1940 to 1948, a professor at

UIUC The University of Illinois Urbana-Champaign (U of I, Illinois, University of Illinois, or UIUC) is a public land-grant research university in Illinois in the twin cities of Champaign and Urbana. It is the flagship institution of the Unive ...

from 1948 to 1958, and finally at

Indiana University Indiana University (IU) is a system of public universities in the U.S. state of Indiana. Campuses Indiana University has two core campuses, five regional campuses, and two regional centers under the administration of IUPUI. * Indiana Univers ...

from 1948 until reaching maximum retirement age in 1974.http://www.genetics.org/content/genetics/133/1/1.full.pdf He was elected to the United States

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

in 1946, the

American Philosophical Society The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communi ...

in 1962, and the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, ...

in 1966. Rhoades was active in the Genetics Society of America, serving as the editor of ''

Genetics Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar worki ...

'' from 1940 to 1948, and later as the Vice President and then President of the GSA. His

research Research is "creative and systematic work undertaken to increase the stock of knowledge". It involves the collection, organization and analysis of evidence to increase understanding of a topic, characterized by a particular attentiveness t ...

maize Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn ( North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. ...

led to important discoveries for basic

genetics Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar worki ...

and the applied science of

plant breeding Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. It has been used to improve the quality of nutrition in products for humans and animals. The goals of plant breeding are to produce cr ...

. He was one of the first cytogenecists to document the pre-meiotic pairing of homologous chromosomes in maize, otherwise referred to as

somatic pairing Somatic may refer to: * Somatic (biology), referring to the cells of the body in contrast to the germ line cells ** Somatic cell, a non-gametic cell in a multicellular organism * Somatic nervous system, the portion of the vertebrate nervous syst ...

(Singh, 2003), and the first to document an instance of meiotic drive, a Mendelian inheritance caused by preferential segregation of certain versions of homologous chromosomes during meiosis. Rhoades also pioneered work in nuclear-cytoplasmic interactions, demonstrating that mutation of the nuclear gene ''iojap'' produced heritable mutations in the genome of chloroplasts which persisted after the nuclear mutation was segregated away. In 1907, Herbert J. Webber started the Synapsis Club, a student/faculty organization at

. Prof.

continued and encouraged his students to become members, including Rhoades. In the 1940s, Rhoades served as the doctoral advisor of geneticist

Ruth Sager Ruth Sager (February 7, 1918 – March 29, 1997) was an American geneticist. Sager enjoyed two scientific careers. Her first was in the 1950s and 1960s when she pioneered the field of cytoplasmic genetics by discovering transmission of genetic tra ...

. The M. Rhoades Early-Career Award, awarded annually by the maize genetics community for significant contributions to genetics research in maize or related species, was named in honor of Rhoades.

Awards

* 1977 Foreign Fellow of the Royal Danish Academy of Science and Letters * 1981 Thomas Hunt Morgan Medal - ( Genetics Society of America) - inaugural award, shared with Barbara McClintock

References

*Carlson, W.R. and Birchler, J.A
Marcus Morton Rhoades, Biographical Memoirs of the National Academy of Sciences
*Singh, R.J. 2003. Plant cytogenetics. CRC Press, USA 1903 births 1991 deaths American geneticists University of Michigan alumni Cornell University alumni Members of the United States National Academy of Sciences Genetics (journal) editors {{US-biologist-stub Members of the American Philosophical Society Fellows of the American Academy of Arts and Sciences