Comparison of Internal Olfactory Anatomy Between Teleost and Elasmobranch Fishes
M.S. Marine Biology
David W. Kerstetter
Olfaction is a fundamental sense utilized for a wide variety of purposes in many animal species, including elasmobranch and teleost fishes. While elasmobranch and teleost linages phylogenetically separated about 450 million years ago, they have since individually evolved many similarities and differences in their internal olfactory organs. The location of the nares, shape of the olfactory organ and size of the sensory brain area devoted to olfaction are a few of the differences noted. In some respects, these differences relate to the habitat in which they live. It has long been thought that elasmobranchs possess superior olfactory abilities over teleosts. Secondary folding of the olfactory epithelium only occurs in elasmobranchs and this suggested a higher sensitivity, but recent studies have shown that marine teleosts and elasmobranchs have similar thresholds to detecting amino acids. Studying the olfactory abilities of elasmobranchs and teleosts lead to discovery of a neural connection. The nervus terminalis was first discovered in elasmobranchs, then teleosts, and only later found in higher mammals. Much additional research on the olfactory structures is required, especially in elasmobranchs, to fully understand the role of this organ in their physiology and lifestyles.
Kristyn Rubertus. 2012. Comparison of Internal Olfactory Anatomy Between Teleost and Elasmobranch Fishes. Capstone. Nova Southeastern University. Retrieved from NSUWorks, . (194)