John Jagger

Longtime UT Dallas professor Dr. John Jagger (center) served as the head of the biology department. His research included discovering the mechanism that causes ultraviolet light to delay bacterial growth. Dr. Solomon Luo MS’78 (right), seen here with his wife, Wendy, and Jagger, credits Jagger for encouraging him to pursue medical school.

Dr. John Jagger, a longtime biology professor at The University of Texas at Dallas who made groundbreaking discoveries about sunlight’s ability to delay bacterial growth, died on Dec. 27 at the age of 90.

Jagger came to Texas in 1965 as an associate professor in the newly established Laboratory of Molecular Sciences at the Graduate Research Center of the Southwest, the institution that became UT Dallas.

At UT Dallas, Jagger and then-graduate student T.V. Ramabhadran discovered the mechanism that causes ultraviolet light to delay bacterial growth. They published their findings in an influential 1976 paper in the journal Proceedings of the National Academy of Sciences.

Jagger served as department head in biology from 1975 to 1977, when UT Dallas began accepting upper-level undergraduate students. He took a strong interest in undergraduate education, helping develop courses for the incoming juniors and seniors, said Dr. Donald Gray, professor emeritus, who worked with Jagger and served as undergraduate biology advisor.

“I remember his opinion that senior faculty, who had the most breadth of background, should be teaching undergraduates and especially the most basic courses,” Gray said.

He added that Jagger’s love of science extended beyond biology.

John Jagger

Dr. John Jagger

John had wide interests beyond those of his grant-supported research, especially in evolution and the possibility of life on other planets, Gray said. Jagger also loved aviation, aquatic sports and travel.

After Jagger retired from UT Dallas in 1986, he returned as a senior lecturer in the early ’90s to teach Evolution of Earth and Life as part of a freshman course, Gray said.

Professors do not always get to find out what impact they have made on their students. But last year Jagger learned about the difference he made decades earlier for one of his students, Solomon Luo MS’78.

Luo, an ophthalmologist with a large private practice in Pennsylvania, credits Jagger for motivating him to attend medical school. He and his wife, Wendy, visited Jagger in Texas last year to thank him and tell him that they would establish the John Jagger Scholarship for Natural Sciences and Mathematics in his honor.

“Dr. Jagger was an influential mentor during my time at UT Dallas, and he went out of his way to assist me with my acceptance into medical school,” Luo said. “If not for Dr. Jagger, I probably wouldn’t have gone down that path.”

Yvonne Callahan, Jagger’s daughter, said her father enjoyed helping others.

“He was honored to be a professor at UT Dallas,” Callahan said. “He absolutely loved working there.”

Memorial Service

A memorial service will be held at noon Saturday at the First Unitarian Church of Dallas, 4015 Normandy Ave., Dallas, TX 75025. Donations may be made to the Nature Conservancy in Texas.

Born in New Haven, Conn., Jagger studied physics at Yale University from 1946 to 1949. He spent two years working in the medical physics department of the Memorial Sloan Kettering Cancer Center in New York City before returning to Yale for a PhD in biophysics in 1954. He conducted postdoctoral research at the Radium Institute in Paris and worked for nine years in the biology division of the Oak Ridge National Laboratory in Tennessee.

After Jagger retired, he wrote several books, including The Nuclear Lion: What Every Citizen Should Know about Nuclear Power and Nuclear War and Science and the Religious Right: What Americans Should Know About Both. He also published two personal books, Cove Days: The Seaside Childhood of a Scientist and From Sea to Prairie: A Lifetime of Poems.

Jagger was preceded in death by his wife, Mary Esther Gaulden Jagger, who was a professor of radiology at UT Southwestern Medical Center at Dallas. He is survived by two children, Thomas Alexander Jagger of Austin and Yvonne Callahan of Flower Mound, and three grandchildren.