Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 2000. / Title from PDF t.p. (viewed on Dec. 11, 2005). Vita. Includes bibliographical references (p. 36-40).

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Seasonal differences in odor preference and social behavior existed among adult meadow voles. During the breeding season, a female preferred its own odor and the odor of males to the odor of another females. Males preferred the odor of females to the odor of other males. Paired encounters between breeding females were more agonistic than encounters between males or encounters between males and females. During the nonbreeding season, a female preferred the the odor of another female to the odor of males. Males did not display an odor preference for any conspecifics. Paired encounters between males were more agonistic than encounters between males and females or encounters between females. Encounters between nonbreeding females contained few agonistic acts. Seasonal differences also existed in the interactions between adults and juveniles. During the early breeding season, adult males were more agonistic than adult females toward juvenile males. During the late breeding season, adult females were more agonistic than adult males toward juvenile males. Encounters between an adult female and a juvenile female in the late breeding season contained few agonistic acts, indicating that overwintering groups are female-biased, and contain juvenile females. Juveniles did not display a shift in odor preferences. They preferred the odor of opposite-sex adults to the odor of same-sex adults, regardless of season. Familiarity, through association during rearing, reduced agonistic behavior between parents and young, and between siblings. Paired encounters between close-kin that were not familiar were agonistic, and similar to encounters between unfamiliar, and unrelated conspecifics. Conspecifics were more agonistic toward closely related males than females. Voles also preferred the odor of a familiar nestmate, independently of genetic relatedness. Familiarity decreased the number of agonistic behaviors between adult females, but increased the number of agonistic behaviors between adult males. Familiarity had no effect on the number of agonistic behaviors between a male and a female. / 2031-01-01

Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Zuoxin Wang, Florida State University, College of Arts and Sciences, Dept. of Psychology. Title and description from dissertation home page (viewed Oct. 1, 2003). Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1955. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 117-120).

The microtine rodents Microtus pennsylvanicus and Synaptomys cooperi are sympatric and occur in the same general habitats. Interspecific competition that varies in intensity would be predicted because of similarities in life history characteristics and temporal variation in Microtus density. Microdistribution of Microtus and Synaptomys was monitored during peak, trough, and early increase phases of a Microtus population cycle. Food habits, activity patterns, and behavioral characteristics were also compared. Field studies at seven sites extended from June 1978 to February 1981. These sites represented a range in habitat suitability for Microtus, as indicated by relative population densities. Undisturbed populations of Microtus and Synaptomys were studied to determine the effects of natural changes in Microtus density on Synaptomys microdistribution. Removal of one species or the other from study grids was used as an experimental tool. Vegetation analysis of study sites included estimates of percentage ground cover and tree/shrub density. Discriminant function analysis was used to determine which of 22 vegetation variables contributed most to distinguishing habitats and microhabitats of the two species. The dominant plant species in habitats where Microtus and Synaptomys coexisted were Juniperus virginiana and Andropogon scoparius. Even at peak population levels, Microtus occurred in relatively low densities (17-50/ha). At the low point in a natural population cycle, the decline or disappearance of Microtus was accompanied by a microdistributional shift by Synaptomys into areas formerly occupied by Microtus. This shift occurred when differences in daily activity rhythms were maximal. Recolonization by Microtus during the early increase phase of population growth resulted in a return to the initial distributional pattern. Displacement of Synaptomys occurred when both species were primarily nocturnal. Removal of Microtus from an experimental grid was followed by colonization by Synaptomys. When Synaptomys was removed from an experimental grid, the distribution of Microtus did not change. Behavioral interaction studies revealed high levels of avoidance and aggression, suggesting that spatial separation is behaviorally maintained. Vegetation studies indicated that habitats with heavy ground cover supported permanent Microtus populations and were inaccessible to Synaptomys. Microhabitat partitioning occurred in heterogeneous habitats with sparse ground cover and denser tree canopy. In the presence of Microtus, Synaptomys occupied microhabitats with higher densities of deciduous trees and shrubs, but shifted to more open microhabitats when Microtus was absent. Food habits analysis indicated that Synaptomys diet consists of vegetation that is low in nutrient content (Andropogon in summer, moss in winter). While Microtus will eat Andropogon (especially in winter), this species also included dicots and other monocots in its diet. Synaptomys diet was more diverse when living on a grid from which Microtus had been removed. These findings suggest that in the southern Appalachians, Synaptomys is excluded from preferred habitats by Microtus and, as a result, lives where cover is sparse and food is low in nutritional value. Competition is relaxed when Microtus declines to trough population density. The combination of wider habitat tolerances by Synaptomys and temporal variation in intensity of competition allows coexistence on a regional basis. / Ph. D.

Thesis (Ph. D.)--Miami University, Dept. of Zoology, 2003. / Title from second page of PDF document. Includes bibliographical references.

The distinct ecological requirements of Microtus xanthognathus (yellow-cheeked vole or taiga vole) and M. pennsylvanicus (meadow vole) warrant accurate discrimination of their remains in studies of paleoecology and past biogeographical shifts. An occlusal length of the lower 1st molars (ml) that is >3.2 mm for M. xanthognathus is the method most frequently used to separate these 2 taxa in archaeological and paleontological samples. However, these measurements alone are unreliable because some specimens of M. pennsylvanicus overlap smaller individuals of M. xanthognathus in size. Therefore, I created and tested a morphometric technique that discriminates Recent lower 1st molars (mis) of M. pennsylvanicus from those of M. xanthognathus, and is applicable to other taxa (both modern and fossil). Despite overlapping occlusal length, my discriminant function based on landmark data correctly classified 100% (n = 53) of Recent m1s from the 2 taxa and 97.7% (43 of 44) of (assumed) m1s of M. pennsylvanicus from an archaeological site from about AD 1200 in central Nebraska. This landmark scheme is applicable to fossil and modern Microtus worldwide. © 2006 American Society of Mammalogists.

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