Career
From 1936 to 1940 he was the assistant curator of herpetology for the American Museum of Natural History. In the late 1930s and early 1940s, with a grant from the Carnegie Corporation he participated in several surveys of various states in Mexico, including one with Karl Patterson Schmidt for the Field Museum of Natural History. In 1941, he was elected vice president of the American Society of Ichthyologists and Herpetologists.
In 1944 he undertook a study on the body temperature of lizards and alligators in Florida, and became chairman and curator for the department of herpetology at the American Museum of Natural History.
From 1948 until 1950 he travelled to Central America to conduct research in Honduras, Nicaragua, Costa Rica and Bimini Island off the Bahamas. In 1949, he published Thermoregulation in Reptiles, a Factor in Evolution in Evolution.
In 1950, he became an instructor at the University of Virginia, and undertook numerous trips to the southwestern United States to do research. In 1952, he was elected president of the American Society Ichthyologists and Herpetologists, which he served as until 1954.
In 1953, he undertook an extensive study of frog vocalizations in the Chiricahua Mountains of Arizona, and released a series of records entitled Sounds of the American Southwest and Sounds of the North American Frogs, as well as a recording of Mexican folk music
In 1955, he was awarded a Guggenheim Fellowship for a year"s research. In 1960, he became a lecturer at the University of Colorado, and began an extensive study of the Oaxaca region of Mexico. In 1966, he was given an honorary Doctor of Laws from University of California, Los Los Angeles In 1978, he became a consultant at the Los Alamos National Environmental Research Park for a year.
Afterwards he continued to travel and conduct further studies, until his death in 1992 in his home in Santa Fe, New Mexico.