Date of Award:

5-1-1977

Document Type:

Thesis

Degree Name:

Master of Science (MS)

Department:

Biology

Department name when degree awarded

Life Sciences:Biology

Committee Chair(s)

James A. MacMahon

Committee

James A. MacMahon

Committee

James A. Gessaman

Committee

Frederic H. Wagner

Abstract

Thermoregulatory and water-conserving capabilities of the nocturnal Perognathus parvus were compared with those of the diurnally active Eutamias minimus. Animals were trapped in Curlew Valley, part of the Great Basin Desert, Utah, and subjected to two experimental phases: Phase I tested their adaptations to normally encountered ambient temperatures; Phase II tested their responses to reversed thermal environments. Testing included definition of the circadian activity rhythm, food and water consumption, fecal water loss, urine osmolality and sodium concentration, body temperature lability, and evaporative water loss. Kidney structure and pelage reflectivity were also examined. P. parvus was more efficient in conserving water through urinary, fecal and evaporative avenues. E. minimus demonstrated greater adaptability to thermal stress with high body temperatures and thick pelage, necessary for retarding heat and radiation penetration. The nocturnal behavior of P. parvus is not physiologically necessary in terms of water balance, but may be important in maintaining thermal balance.

Share

COinS