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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ecological separation of Peromyscus maniculatus Bairdii and Peromyscus leucopus novebo racensis (Rodentia) in southcentral Ohio,

Birch, William L. January 1977 (has links)
Thesis (M.S.)--Ohio State University. / Bibliography: leaves 80-86. Available online via OhioLINK's ETD Center
2

The identification and distribution of two species of Peromyscus in southeastern Ontario

Lanko, Joyce Laurian January 1962 (has links)
One hundred and sixty-nine mice of Peromyscus leucopus noveboracensis and Peromyscus maniculatus gracilis were examined for characters to best separate them. Each species was obtained from an area in Ontario where it was known to be the only one present. An additional 12 mice of both species were obtained from an area of sympatry. The best characters found to separate them were, in order of importance: ear length, interparietal length, tail length, skull length, and rostral length. Although ear length and interparietal length separated most of the individuals, there were still individuals that could not be separated. The two species were found to be completely separable, using either one of two indices: Ear length X tall length X interparietal length skull length or, Ear length X tail length X interparietal length rostral length. With skull length, P. 1. noveboracensis has an index value of 2.57-4.09 and P. m. gracilis has an index value of 4.26-7.90. With rostral length, P. 1. noveboracensis has an index value of 7.39-12.50 and P. m. gracilis has an index value of 12.83-22.77. Six crossbreeding experiments were attempted between P. 1. noveboracensis and four subspecies of P. maniculatus. The animals were kept together for periods ranging from 71 days to over a year. No offspring resulted. Three pairs of P. leucopus and four pairs of P. maniculatus were kept for the same periods of time in the same room, as a control. One pair of leucopus produced two litters, another pair produced one, and the third pair, none. Two pairs of maniculatus produced one litter each and the two pairs, none. P. m. gracilis was not as excitable or nervous as P. 1. noveboracensis and was therefore easier to handle. Although the ranges of P. 1. noveboracensis and P. m. gracilis differ, the mice meet in a zone of overlap where they occur sympatrically. Correlations were made between the ranges of the mice and vegetation, food preference, temperature tolerance, water requirement, morphology, color of pelage, and behavior. P. m. gracilis was found to occur in coniferous and P. 1. noveboracensis in deciduous vegetation. No correlation was found between the ranges of the mice and food preference, temperature tolerance, water requirement, morphology, and color of pelage. Correlation between the ranges of the mice and their behavior was doubtful. Preliminary tests were made of the ability of one species to discriminate between its odor and that of the other species. Results showed that a mouse entered more often and stayed longer in a chamber containing the odor of its own species. A chamber containing odor of either species was preferred to the control chamber without odor. / Science, Faculty of / Zoology, Department of / Graduate
3

A genetic and behavioral analysis of intraspecific variation in mating behavior of deer mice (Peromyscus maniculatus)

Wright, LaToya C. January 2007 (has links) (PDF)
Thesis (M.S.)--University of North Carolina at Greensboro, 2007. / Title from PDF t.p. (viewed Oct. 18, 2007). Directed by Matina C. Kalcounis-Rüppell; submitted to the Dept. of Biology. Includes bibliographical references (p. 26-30).
4

A potential role for gut macroparasites in the population dynamics of Central Pennsylvania white-footed mice Peromyscus leucopus

Vandegrift, Kurt J. Hudson, Peter J., January 2008 (has links)
Thesis (Ph.D.)--Pennsylvania State University, 2008. / Mode of access: World Wide Web. Thesis advisor: Peter J. Hudson.
5

Demography and dispersal in island and mainland populations of the deer mouse, Peromyscus maniculatus

Sullivan, Thomas Priestlay January 1976 (has links)
If dispersal is reduced on islands, then the demography of island populations of deer mice should be different from that of mainland populations., Areas of 1.1 ha were periodically cleared of mice on Samuel Island (206 ha) and Saturna Island (3102 ha) in the Gulf Islands of southwestern British Columbia., A similar experiment was conducted on the mainland at Maple Ridge, B.C., The average density of mice per hectare on Saturna (43.5) was twice that on Samuel Island (22.0) and nearly two and one-half times higher than that on the mainland (18.7). The reproductive rate, as measured by length of breeding season, number of successful pregnancies, proportion of breeding animals, and number of recruits surviving to breed, was much higher on Samuel Island than on either Saturna or the mainland. Survival was lowest on Samuel Island, with little difference between the mainland and Saturna Island., Mice on Samuel Island grew more than five times faster than mainland animals, and Saturna growth rates were double those on the mainland. Island adult males showed very few aggressive tendencies in laboratory behaviour tests compared with the seasonal changes in aggression reported in the literature for mainland deer mice. Dispersal (or colonization) rate was reduced on the two islands compared with that on the mainland. Eecruitment of young animals occurred throughout the breeding season on the islands but was delayed until the end of breeding on the mainland. There was little difference in the demographic attributes of control populations when compared with those of colonist populations on either the mainland or the two islands. These results indicate that seasonal changes in aggressiveness of the adult population may be sufficient but not necessary to determine breeding density and seasonal changes in survival of juvenile deer mice., A more intensive study is reguired, but regulatory processes in populations of Peromy_scus oa&iculatus may be different on islands and perhaps should not be generalized over different geographic areas. / Science, Faculty of / Zoology, Department of / Graduate
6

Population processes in Peromyscus: an experimental approach

Fairbairn, Daphne Janice January 1976 (has links)
This study examined seasonal variability in demography, genetic composition, and behavior, in populations of deermice (Peromyscus maniculatus), Particular attention was paid to the possible role of aggression and dispersal in determining densities. Three types of populations were examined by means of biweekly live-trapping: undisturbed populations, a population removed continuously, and a population removed annually, at the onset of breeding. The two removal experiments sampled dispersing mice. The genetic data consisted of allelic frequencies at three blood protein loci, detected by starch gel electrophoresis: transferrin, an esterase, and glutamate oxalate transaminase. Behavior of field animals was examined in three laboratory tests. Females which began breeding in early spring suffered heavy mortality, and this resulted in a decline in female density. Females heterozygous at only one locus were selected for over this period. Males became aggressive and spaced themselves out as they began breeding, and light-weight, less aggressive males dispersed. This resulted in a decline in male density. While males were breeding, juveniles, particularly juvenile males, survived poorly, and few entered the populations. Light, non-breeding, subordinate males continued to disperse. As breeding stopped, males which continued to breed moved around, and juveniles survived well. The population increased to its maximum density in late fall. Over the winter, survival was good, dispersal low, and spacing behavior at its minimum. Dispersing males were lighter, showed less aggression in a neutral arena, and were more active than resident males. They differed genetically from residents, although there was no evidence of selection on males in control populations. Dispersing females were lighter, showed less exploratory behavior in an unfamiliar maze, and were more active than resident females. Dispersal was not selective in females. Populations settling in a depopulated area continued to differ genetically from control populations, but within two months resembled control populations demographically and behaviorally. The only difference was that a lower proportion of colonists bred, and this was compensated for by recruitment of juveniles from surrounding areas. The major hypotheses suggested by this study are: 1) Spacing out and dispersal of males in the spring is a response to mortality of early-breeding females, and thus it is this latter mortality which determines breeding densities. 2) Dispersal has two components: dispersal of subordinate mice in response to social pressure, and innate dispersal of more spontaneously active mice. / Science, Faculty of / Zoology, Department of / Graduate
7

The effect of diet on reproductive inhibition in photoresponsive white-footed mice (Peromyscus leucopus) /

Gibbons, Connie May. January 2008 (has links)
Thesis (Honors)--College of Wiliam and Mary, 2008. / Includes bibliographical references (leaves 47-49). Also available via the World Wide Web.
8

Mitochondrial-DNA variation and the evolutionary affinities of the Peromyscus maniculatus complex from western North America

Walker, Mindy Lynn 12 April 2006 (has links)
Intraspecific phylogeography and the phylogenetic relationships of recently-diverged taxa are best assessed with the use of a genetic marker that coalesces rapidly and thus provides phylogenetically informative characters for closely-related taxa. Mitochondrial DNA (mtDNA) fits these criteria and was thereby ideal for analyzing genetic variation within and among the youngest taxonomic members of the Peromyscus maniculatus species group, P. sejugis (restricted to two islands in the Sea of Cortés), P. maniculatus (distributed throughout North and Central America) and P. keeni (a coastal species restricted to the Pacific Northwest of North America). The approach utilized in this research involved sequencing a 1439 base-pair (bp) region of mtDNA for a total of 581 specimens representing 45 different geographic localities from along the west coast of North America. The sequences obtained were used to assess the partitioning of genetic diversity within and among these taxa, address phylogenetic and taxonomic concerns about the western representatives of the P. maniculatus species group and discuss the post-Pleistocene biogeography of the west coast of North America. Analysis of mtDNA sequence variation, considered within the framework of a phylogenetic species concept, revealed the existence of two evolutionarily significant units of P. sejugis as well as a previously unrecognized sibling species nested within the Pacific coastal range of P. maniculatus. Moreover, analysis of intraspecific sequence divergence allowed for the identification of the ice-free refugium thought to harbor P. keeni throughout glaciation during the Pleistocene epoch. This work will establish the foundation for additional examination of cryptic genetic variation in different morphotypes of P. maniculatus and continue the precedent for recognizing P. maniculatus-group taxa that reflect true evolutionary entities.
9

Mitochondrial-DNA variation and the evolutionary affinities of the Peromyscus maniculatus complex from western North America

Walker, Mindy Lynn 12 April 2006 (has links)
Intraspecific phylogeography and the phylogenetic relationships of recently-diverged taxa are best assessed with the use of a genetic marker that coalesces rapidly and thus provides phylogenetically informative characters for closely-related taxa. Mitochondrial DNA (mtDNA) fits these criteria and was thereby ideal for analyzing genetic variation within and among the youngest taxonomic members of the Peromyscus maniculatus species group, P. sejugis (restricted to two islands in the Sea of Cortés), P. maniculatus (distributed throughout North and Central America) and P. keeni (a coastal species restricted to the Pacific Northwest of North America). The approach utilized in this research involved sequencing a 1439 base-pair (bp) region of mtDNA for a total of 581 specimens representing 45 different geographic localities from along the west coast of North America. The sequences obtained were used to assess the partitioning of genetic diversity within and among these taxa, address phylogenetic and taxonomic concerns about the western representatives of the P. maniculatus species group and discuss the post-Pleistocene biogeography of the west coast of North America. Analysis of mtDNA sequence variation, considered within the framework of a phylogenetic species concept, revealed the existence of two evolutionarily significant units of P. sejugis as well as a previously unrecognized sibling species nested within the Pacific coastal range of P. maniculatus. Moreover, analysis of intraspecific sequence divergence allowed for the identification of the ice-free refugium thought to harbor P. keeni throughout glaciation during the Pleistocene epoch. This work will establish the foundation for additional examination of cryptic genetic variation in different morphotypes of P. maniculatus and continue the precedent for recognizing P. maniculatus-group taxa that reflect true evolutionary entities.
10

Ecological niche responses of small mammals to gypsy moth disturbance /

Tomblin, David Christian. January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 154-164). Also available via the Internet.

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