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

pituitary gland In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...

and for isolating the hormone

prolactin Prolactin (PRL), also known as lactotropin, 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 secreted from the pit ...

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. A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University ...

in biology from

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 Universi ...

in 1902 and a PhD in zoology at the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

in 1907. He taught physiology and biology in

Saint Louis, Missouri St. Louis () is the second-largest city in Missouri, United States. It sits near the confluence of the Mississippi and the Missouri Rivers. In 2020, the city proper had a population of 301,578, while the bi-state metropolitan area, which ...

and

Puerto Rico Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...

, 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 , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...

in South America and

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...

. In 1912 he was appointed a research associate at the

Carnegie Institution The Carnegie Institution of Washington (the organization's legal name), known also for public purposes as the Carnegie Institution for Science (CIS), is an organization in the United States established to fund and perform scientific research. T ...

Cold Spring Harbor Laboratory Cold Spring Harbor Laboratory (CSHL) is a private, non-profit institution with research programs focusing on cancer, neuroscience, plant biology, genomics, and quantitative biology. It is one of 68 institutions supported by the Cancer Centers ...

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.

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 proces ...

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 that is regurgitated to young birds. It is found among all pigeons and doves where it is referred to as pigeon milk. An analog to crop milk is also secreted from the esopha ...

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.'' 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 an American international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific respons ...

and was published in the journal

Science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

and covered by the

New York Times ''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid d ...

. Riddle was featured on the cover of

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

in January 1939. In 1958, Riddle was named the Humanist of the Year by the American Humanist Association. 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 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. The population was 39,764 at the 2020 census. Despite many thinking it was named for flora ...

, in 1968.

Books

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

References

External links

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