Oscar Riddle (September 27, 1877 – November 29, 1968) was an American biologist. He is known for his research into the

pituitary gland The pituitary gland or hypophysis is an endocrine gland in vertebrates. In humans, the pituitary gland is located at the base of the human brain, brain, protruding off the bottom of the hypothalamus. The pituitary gland and the hypothalamus contr ...

and for isolating the hormone

prolactin Prolactin (PRL), also known as lactotropin and mammotropin, is a protein best known for its role in enabling mammals to produce milk. It is influential in over 300 separate processes in various vertebrates, including humans. Prolactin is secr ...

Early career

Riddle was born and raised on a farm in Cincinnati, Indiana, where he was one of eight siblings. He received a B.S. in biology from

Indiana University Indiana University (IU) is a state university system, system of Public university, public universities in the U.S. state of Indiana. The system has two core campuses, five regional campuses, and two regional centers under the administration o ...

in 1902 and a

PhD A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...

in zoology at the

University of Chicago The University of Chicago (UChicago, Chicago, or UChi) is a Private university, private research university in Chicago, Illinois, United States. Its main campus is in the Hyde Park, Chicago, Hyde Park neighborhood on Chicago's South Side, Chic ...

in 1907. He taught physiology and biology in

Saint Louis, Missouri St. Louis ( , sometimes referred to as St. Louis City, Saint Louis or STL) is an independent city in the U.S. state of Missouri. It lies near the confluence of the Mississippi and the Missouri rivers. In 2020, the city proper had a populatio ...

and

Puerto Rico ; abbreviated PR), officially the Commonwealth of Puerto Rico, is a Government of Puerto Rico, self-governing Caribbean Geography of Puerto Rico, archipelago and island organized as an Territories of the United States, unincorporated territo ...

, and he embarked on natural history expeditions to the

Orinoco River The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers approximately 1 million km2, with 65% of it in Venezuela and 35% in Colombia. It is the List of rivers by discharge, f ...

in South America and

Cuba Cuba, officially the Republic of Cuba, is an island country, comprising the island of Cuba (largest island), Isla de la Juventud, and List of islands of Cuba, 4,195 islands, islets and cays surrounding the main island. It is located where the ...

. In 1912 he was appointed a research associate at the

Carnegie Institution The Carnegie Institution for Science, also known as Carnegie Science and the Carnegie Institution of Washington, is an organization established to fund and perform scientific research in the United States. This institution is headquartered in Wa ...

Cold Spring Harbor Laboratory Cold Spring Harbor Laboratory (CSHL) is a private, non-profit institution with research programs focusing on cancer, neuroscience, botany, genomics, and quantitative biology. It is located in Laurel Hollow, New York, in Nassau County, on ...

in Long Island. Biography of Oscar Riddle written by George W. Corner. This biography includes a list of published works written by Riddle. He stayed with the Cold Spring Harbour institution for the rest of his career, until his retirement in 1945. Riddle was elected to the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

in 1926, the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) 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, and other ...

in 1934, and the United States

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, 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 ...

in 1939.

Research

Oscar Riddle published many dozens of original research reports in the 30 years 1916-1945. His research spanned endocrinology, the physiology of reproduction, animal pigmentation, and the nature and functional basis of sex. He is most remembered for his research into the major pituitary hormone

. It was shown by other researchers in 1928 that an aqueous mash of pituitary cells can induce

lactation Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The process ...

in female mammals. Riddle and his colleagues were the first to isolate prolactin, which was named by Riddle in 1932. Also around 1932 Riddle was earliest to show that the prolactin protein induces the secretion of

crop milk Crop milk is a secretion from the lining of the crop of parent birds in some species that is regurgitated to young birds. It is found among all pigeons and doves where it is also referred to as pigeon milk. Crop milk is also secreted from the c ...

in pigeons and other birds. During the 1930s he participated in leading-edge demonstrations on the effects of prolactin injections in animals.

Humanism

Riddle was a devout

atheist Atheism, in the broadest sense, is an absence of belief in the existence of deities. Less broadly, atheism is a rejection of the belief that any deities exist. In an even narrower sense, atheism is specifically the position that there no ...

and held the conviction that religion poses a serious threat to scientific advancements.Humanist profile: Oscar Riddle 1958: Humanist of the Year.
''

American Humanist Association The American Humanist Association (AHA) is a 501(c) organization, non-profit organization in the United States that advances secular humanism. The American Humanist Association was founded in 1941 and currently provides legal assistance to defe ...

.'' He garnered national attention for a speech debunking superstition in 1936. His speech was delivered to the

American Association for the Advancement of Science The American Association for the Advancement of Science (AAAS) is a United States–based international nonprofit with the stated mission of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsib ...

and was published in the journal

Science Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

and covered by the

New York Times ''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...

. Riddle was featured on the cover of

Time (magazine) ''Time'' (stylized in all caps as ''TIME'') is an American news magazine based in New York City. It was published Weekly newspaper, weekly for nearly a century. Starting in March 2020, it transitioned to every other week. It was first publishe ...

in January 1939. In 1958, Riddle was named the Humanist of the Year by the

. He was president of the American Rationalist Federation in 1959 and 1960. In 1937, Riddle married Leona Lewis, a music teacher. They had no children. He died of

prostate cancer Prostate cancer is the neoplasm, uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of the prostate tissue is usually detected through Screening (medicine), screening tests, ...

at the age of 91 in

Plant City, Florida Plant City is an incorporated city in Hillsborough County, Florida, United States, approximately midway between Brandon and Lakeland along Interstate 4. It is part of the Tampa Bay area. The population was 39,764 at the 2020 census. Despite ma ...

, in 1968.

Books

*''Endocrines and Constitution in Doves and Pigeons'' (1947) *''The Unleashing of Evolutionary Thought'' (1952)

References

External links

* {{DEFAULTSORT:Riddle, Oscar American atheists 1877 births 1968 deaths People from Greene County, Indiana 20th-century American biologists Members of the American Philosophical Society