James Stewart "Stew" Otto, 84, a radiation biologist who was involved with atomic bomb tests in Nevada and on Eniwetok Island and worked with Sam the space monkey, died June 29 in Lynn Haven, Fla.
As a Navy researcher during World War II, Otto studied the effects of radiation on animals and helped advise President Harry S. Truman before atomic bombs were dropped on Hiroshima and Nagasaki, Japan.
Later, Otto worked with the Navy's Animal Research Institute in Bethesda, Md., heading the organization from 1959 to 1973. As part of a study of the effects of space travel on animals and humans, Otto worked extensively with Sam, the rhesus monkey sent into space in 1959 before manned flights to the moon. The monkey returned to Earth safely and was recovered from his capsule that splashed down in the Atlantic.