Columbia University in the City of New York, 116th St & Broadway, New York, NY 10027, United States
In 1909, Calvin Bridges entered Columbia University and received his Bachelor of Science degree in 1912.
In 1916, Bridges earned his Doctor of Philosophy degree in zoology from Columbia University.
Career
Achievements
Membership
National Academy of Sciences
1936
National Academy of Sciences, 2101 Constitution Ave NW, Washington, DC 20418, United States
In 1936, Calvin Bridges was elected to the National Academy of Sciences for his work with Drosophila.
Columbia University in the City of New York, 116th St & Broadway, New York, NY 10027, United States
In 1909, Calvin Bridges entered Columbia University and received his Bachelor of Science degree in 1912.
In 1916, Bridges earned his Doctor of Philosophy degree in zoology from Columbia University.
Non-Disjunction as Proof of the Chromosome Theory of Heredity
(There are now about fifty sex-linked mutations known in D...)
There are now about fifty sex-linked mutations known in Drosophila, and the data collected in their investigation are the most extensive known in experimental breeding. The arrangement of the sex-linked genes in a linear series and the establishment of the relative distances between the loci are based upon over half a million flies. The work on non-disjunction deals directly with the best known of these sex-linked characters, and therefore rests upon a very firm Mendelian foundation.
Calvin Blackman Bridges was an American geneticist, who studied chromosomes and heredity in the United States throughout the early twentieth century.
Background
Calvin B. Bridges was born on January 11, 1889, in Schuyler Falls, New York, the only child of Leonard Victor Bridges and Amelia Charlotte Blackman. Tragically, Calvin's mother died when he was two years old, and his father died a year later, leaving the young Calvin an orphan. Bridges was subsequently taken in and raised by his grandmother.
Education
When Calvin Bridges was fourteen, he was sent to Plattsburg to attend high school. Because of his deficient primary school training and because he worked to help support himself, he did not graduate from high school until he was twenty. His record was good enough, however, for him to be offered scholarships at both Cornell and Columbia. He chose the latter and entered as a freshman in 1909.
During his first year at Columbia, he took a biology course taught by Morgan. In his sophomore year, Bridges was given a position as an assistant in Morgan’s lab at Columbia University. At that time, Morgan studied heredity using Drosophila, which required Morgan to breed flies in milk bottles. Bridges initially cleaned the bottles.
In 1912, after three years of school, Bridges graduated from Columbia with a Bachelor of Science degree.
After receiving his undergraduate degree, Bridges earned his Doctor of Philosophy degree in zoology from Columbia University in 1916.
After graduation, Calvin Bridges worked with Morgan as a research associate of the Carnegie Institution of Washington. His pioneering work helped prove that genes on chromosomes pass along hereditary traits. It helped advance the understanding of how abnormalities in chromosome structure are related to changes in physical traits and how the sex of an organism is genetically determined. By studying chromosomes with missing segments, Bridges also constructed some of the earliest chromosome maps. Bridges, with Morgan and Alfred Henry Sturtevant, published these results in 1925. That same year he published "Sex in Relation to Chromosomes and Genes," demonstrating that sex in Drosophila is not determined simply by the "sex chromosomes" (X and Y) but is the result of a "chromosomal balance" - a mathematical ratio of the number of female sex chromosomes (X) to the number of "nonsex" chromosomes (autosomes).
In 1928 Bridges moved with Morgan to the California Institute of Technology, Pasadena, where he constructed detailed gene maps of the giant chromosomes found in the salivary gland cells of the fruit fly larva. Later he discovered an important class of Drosophila mutants caused by gene duplications.