Publication Date:
2022-05-26
Description:
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February, 2005
Description:
In this thesis, the relationships of olfactory sensitivity to three biological variables were tested. The sensitivity of a marine mammal, the sea otter (Enhydra lutris) was measured in order to determine whether a marine lifestyle results in impaired olfaction. The effect of dietary relevance on sensitivity to specific odorants was evaluated. Finally, a new morphometric model of olfactory uptake efficiency was developed and tested against behavioral measurements of olfactory sensitivity in twelve mammalian species from five orders. Olfactory thresholds were obtained for the first time from two sea otters for seven odorant compounds from various natural sources. Otters were trained using operant conditioning to participate in direct behavioral testing. Sea otter olfactory sensitivity was comparable to that of previously studied terrestrial mammals. The incidence of an odorant in the diet of the olfactor was found to influence specific sensitivity to that compound but to varying degrees among different mammalian orders. Nasal cavity specimens were measured using radiologic (CT scan) and histologic (light microscopy) techniques. Surface areas and volumes of the nasal cavity were used to calculate the Olfactory Uptake Efficiency (OUE). OUE is significantly related to olfactory bulb volume. A possible relationship was found between OUE and general olfactory sensitivity.
Description:
I am grateful to the Oregon Zoo and the Oregon Coast Aquarium, whose exhibit animals provided the olfactory threshold data, as well as the Monterey Bay Aquarium, the Point Defiance Zoo and the New England Aquarium, which also participated. Nasal cavity specimens were generously donated by the American Museum of Natural History, the Whitehead Institute at the Massachusetts Institute of Technology, the Biology Department of MIT, the California Oiled Wildlife Network, the Harvard Museum of Comparative Zoology, the Institute for Hydrology and Ecology at Monk's Hood, Tufts Veterinary School, the New England Regional Primate Research Center, Lion Country Safari Zoo, and the Cameron Park Zoo. Funding was provided by the Woods Hole Oceanographic Institution's Education Department, Biology Department and Ocean Ventures Fund, the National Science and Engineering Research Council of Canada, the Gen Foundation, the Massachusetts Institute of Technology's Student Assistance Fund, the European Chemoreception Research Organization, the Society for Experimental Biology, the Company of Biologists, and the Office of Naval Research.
Keywords:
Olfactometry
;
Mammals
Repository Name:
Woods Hole Open Access Server
Type:
Thesis
Format:
34912025 bytes
Format:
338448972 bytes
Format:
545085713 bytes
Format:
533504 bytes
Format:
application/pdf
Format:
application/vnd.ms-excel
Format:
application/zip
Format:
application/zip
Permalink