Browsing by Subject "Rodents"
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Item A comparison of chromosomal and paleontological evidences of evolution in rodents(Texas Tech University, 1954-05) Rosenbaum, Jean AnnNot availableItem A comparison of chromosomal and paleontological evidences of evolution in rodents(Texas Tech University, 1954-05) Rosenbaum, Jean AnnNot availableItem A comparison of the rodent faunas in sandhill habitats from the northern Chihuahuan Desert in Texas(2005-08) Brant, Joel G.; Phillips, Carleton J.; Jones, Clyde J.; Baker, Robert J.; Strauss, Richard E.; McIntyre, Nancy E.During the latter years of the twentieth century, scientists and naturalists began placing increasing emphasis on the importance of the world’s rich diversity of species. In keeping with this trend, biologists have increased their efforts to learn as much about the biodiversity of every environment and have demonstrated that the results of these efforts are essential to understanding how diversity is maintained in each environment. The objective of this study is to characterize the rodent communities inhabiting sand dune habitats at two protected areas in the northern Chihuahuan Desert. The sand dunes at each locality were divided into three dune habitats (cover sands, vegetated dunes, and active dunes) based on substrate stability and vegetative cover. Sampling was conducted in each of these dune habitats from November 2000 to August 2003 (Monahans Sandhills State Park) and October 2003 to February 2004 (Guadalupe Mountains National Park). Twenty-nine species of mammals were recorded from Monahans Sandhills State Park (MSSP) with Dipodomys ordii being the most abundant species. The sand dunes at Guadalupe Mountains National Park (GMNP) yielded 23 mammalian species with the most abundant species being Dipodomys merriami. Rodent diversity was significantly higher in sand dune areas than in the surrounding cover sands at both parks. Active dunes from both parks had significantly more species and were more diverse than the cover sands habitats. The habitat heterogeneity hypothesis is the most likely mechanism that accounts for these results and the maintenance of this level of biodiversity in sand dune environments.Item A comparison of the rodent faunas in sandhill habitats from the Northern Chihuahuan Desert in Texas(Texas Tech University, 2005-08) Brant, Joel G.; Phillips, Carleton J.; Jones, Clyde J.; Baker, Robert J.; Strauss, Richard E.; McIntyre, Nancy E.During the latter years of the twentieth century, scientists and naturalists began placing increasing emphasis on the importance of the world’s rich diversity of species. In keeping with this trend, biologists have increased their efforts to learn as much about the biodiversity of every environment and have demonstrated that the results of these efforts are essential to understanding how diversity is maintained in each environment. The objective of this study is to characterize the rodent communities inhabiting sand dune habitats at two protected areas in the northern Chihuahuan Desert. The sand dunes at each locality were divided into three dune habitats (cover sands, vegetated dunes, and active dunes) based on substrate stability and vegetative cover. Sampling was conducted in each of these dune habitats from November 2000 to August 2003 (Monahans Sandhills State Park) and October 2003 to February 2004 (Guadalupe Mountains National Park). Twenty-nine species of mammals were recorded from Monahans Sandhills State Park (MSSP) with Dipodomys ordii being the most abundant species. The sand dunes at Guadalupe Mountains National Park (GMNP) yielded 23 mammalian species with the most abundant species being Dipodomys merriami. Rodent diversity was significantly higher in sand dune areas than in the surrounding cover sands at both parks. Active dunes from both parks had significantly more species and were more diverse than the cover sands habitats. The habitat heterogeneity hypothesis is the most likely mechanism that accounts for these results and the maintenance of this level of biodiversity in sand dune environments.Item Biosystematics of the genus Reithrodontomys on the Southern High Plains(Texas Tech University, 1995-08) Lynch, Maryann RoseDetermining and understanding evolutionary relationships of organisms is a goal in systematics. Initial studies of the genus Reithrodontomys addressed the subspecific affinities of species within the genus in portions of their ranges (Hooper 1952; Jones and Mursaloglu 1961). The focus of subsequent investigations has evolved beyond the taxonomic level of the subspecies, and has paralleled the development of new genetic and molecular techniques, such as standard karyotype analysis (Shellhammer 1967; Carleton and Myers 1979; Engstrom et al. 1981), G- and C- banding of chromosomes (Robbins and Baker 1980), starch-gel electrophoresis of allozymes (Arnold et al. 1983), and most recently, in situ hybridization of satellite DNA (Hamilton et al. 1990). Thus, many of the questions regarding Reithrodontomys pertain to phylogenetic relationships. Despite the many studies of Reithrodontomys, important questions relative to variation among populations of species within the genus remain unanswered. Reithrodontomys megatotis, from the Southern High Plains in West Texas, represents a taxon in which variation within and among populations is not well understood. This species Is a relatively rare or elusive inhabitant of the area, and to date, these characteristics have prevented a thorough study of populational differences in this geographical region. Currently, two subspecies (R m. aztecus, R. m. megatotis), are recognized rom this expanse in West Texas. The purpose of this study is to examine specimens from this region, and through the use of phenetic techniques and statistical analyses, elucidate the extent of nongeographic and geographic variation in R. megatotis, and assess the subspecific status of R. megatotis on the Southern High Plains.Item Molecular systematics of neotomine-peromyscine rodents based on nuclear DNA sequences(Texas Tech University, 2003-05) Reeder, Serena AnnNot availableItem Population dynamics of rodents of the Mesquite Plains-High Plains ecotone(Texas Tech University, 1968-06) Womochel, Daniel RobertNot available