He is well known for over 30 years of research on the secondary sexual characteristics of salamanders and more generally on comparative histoanatomy of the urogenital systems of vertebrates.
[3] Sever earned his Ph.D. from Tulane University in 1974 where he studied the secondary sexual characters of plethodontid salamanders under Harold A.
[3] Stanley E. Trauth, in his capacity as president of the Herpetologist's League, stated that Sever's research contributions were why he was chosen.
"Early in his studies, Dave's histological research focused primarily on salamander cloacal anatomy and, specifically, the spermatheca or sperm storage structure in these animals," said Trauth.
"His numerous papers on these structures have dominated the international literature on this subject for decades," and "I consider Dave to be today's world leading authority on vertebrate reproductive histology".