The preference for a rocky situation was analyzed under laboratory conditions. In three-compartmented choice boxes, Peromyscus californicus and P. eremicus chose a compartment with rocks and a sandy floor over a compartment with just a sandy floor but P. maniculatus did not show a preference. In a similar experiment, in continual total darkness, the three species chose the compartment with the rocks. UM-key did not prefer the compartment with rocks when the rocks were encased in plastic and were under a normal light regime. When allowed a choice between an empty dark compartment and an empty lighted compartment exposed to a normal light regime, they preferred the darkened compartment I conclude that preference for the rocks is elicited by both the shading and the tactile stimulation they provide rather than by any preference for their visual form.

Simultaneously, several biological and methodological variables were monitored. The biological variables were: species, sex experience (whether previously tested and whether born in captivity), and initial choice. The statistical test of the choice in each of the experiments considered the effect of the variables being monitored. There was no consistent pattern in the effect of these variables.

Examination of the results in different time periods implies: 1) one hour is not enough to determine preference (whereas one night is); 2) whenever there was choice at night, there was choice during the day and when there was none at night, there was none during the day; and 3) day choice was in the same direction as night choice.

LLU Discipline





Graduate School

First Advisor

Leonard R. Brand

Second Advisor

Norman M. Case

Third Advisor

Earl W. Lathrop

Fourth Advisor

Elwood S. McCluskey

Fifth Advisor

Paul Y. Yahiku

Degree Name

Doctor of Philosophy (PhD)

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Year Degree Awarded


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Page Count

vi; 42

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Loma Linda University Libraries

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This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

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Loma Linda University. Del E. Webb Memorial Library. University Archives

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