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Articles 1 - 13 of 13
Full-Text Articles in Life Sciences
Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk
Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk
Theses and Dissertations - UTB/UTPA
Audubon's Oriole ( Icterus graduacauda ) was known historically throughout the Lower Rio Grande Valley (LRGV) of Texas, but its breeding range has now declined to mainly riparian habitat in Starr County. Habitat loss, degradation, and fragmentation, and brood parasitism by Bronzed Cowbirds ( Molothrus aeneus ) are likely causes of this decline. Habitat patches where Audubon's Orioles were present were larger, with a larger vertical range of canopy, greater vegetation volume, greater richness of bird and woody plant species, less local deforestation, and less local habitat fragmentation than where Audubon's Orioles were absent. Bronzed Cowbirds showed no numeric correlation …
Mechanical Properties Of The Integument Of The Common Gartersnake, Thamnophis Sirtalis (Serpentes: Colubridae), Gabriel Rivera
Mechanical Properties Of The Integument Of The Common Gartersnake, Thamnophis Sirtalis (Serpentes: Colubridae), Gabriel Rivera
Biological Sciences Theses & Dissertations
The evolution of the ophidian feeding mechanism has involved substantial morphological restructuring associated with the ability to ingest relatively large prey. Previous studies examining the morphological consequences of macrophagy have concentrated on modifications of the skull and cephalic musculature. Although it is evident that macrophagy requires highly compliant skin, the mechanical properties of the ophidian integument have received limited attention, particularly in the context of feeding. I examined mechanical properties of skin along the body axis in male Thamnophis sirtalis (Colubridae). From each of 11 specimens, I examined nine circumferential strips of skin, each spanning 10 ventral scales, spaced at …
Geographic Variation In The Morphology Of Crotalus Horridus (Serpentes: Viperidae), John Robert Allsteadt
Geographic Variation In The Morphology Of Crotalus Horridus (Serpentes: Viperidae), John Robert Allsteadt
Biological Sciences Theses & Dissertations
The Timber Rattlesnake (Crotalus horridus) occurs in discontinuous populations throughout the eastern and central United States. The species exhibits high levels of polymorphism in morphological traits, especially in coloration and pattern. Previous studies recognized either distinct northern and southern subspecies or three regional morphs (northern, southern, and western), but conflicting data sets and limited geographic sampling of previous studies have left the relationships among those regional variants unclear. In this study, univariate and multivariate statistics, together with a geographic information system, were used to analyze geographic variation in 36 morphological characters recorded from 2,420 specimens of C. horridus …
Hybridization Between The Watersnakes Nerodia Sipedon And Nerodia Fasciata, In The Carolinas: A Morphological And Molecular Approach, Konrad Mebert
Hybridization Between The Watersnakes Nerodia Sipedon And Nerodia Fasciata, In The Carolinas: A Morphological And Molecular Approach, Konrad Mebert
Biological Sciences Theses & Dissertations
A few traditionally applied diagnostic characters of color pattern were compared with an additional set of morphological and genetic characters to evaluate differences between Nerodia sipedon and N. fasciata and to study the dynamics across their hybrid zone in the Carolinas. Many of the morphological characters exhibited significant interspecific differences, although only the number of dorsally complete crossbands (CBa) was diagnostic by itself. A discriminant function analysis of morphological characters was successful in separating both taxa. Species-specific nuclear markers, identified by the AFLP (Amplified Fragment Length Polymorphism) technique were nearly fixed and served as diagnostic markers. They revealed extensive introgression …
Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held
Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held
Dissertations, Theses, and Masters Projects
No abstract provided.
Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West
Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West
Dissertations, Theses, and Masters Projects
No abstract provided.
Distribution, Abundance, And Home Range Of The Whip-Poor-Will (Caprimulgus Vociferus) In A Managed Forest Landscape, Michael Daniel Wilson
Distribution, Abundance, And Home Range Of The Whip-Poor-Will (Caprimulgus Vociferus) In A Managed Forest Landscape, Michael Daniel Wilson
Dissertations, Theses, and Masters Projects
No abstract provided.
A Genetic Analysis Of The Intraspecific Relationships Of Tropical Marine Shorefishes Common To Bermuda And The Southeastern Atlantic Coast Of The United States, Kelly R. Johnson
A Genetic Analysis Of The Intraspecific Relationships Of Tropical Marine Shorefishes Common To Bermuda And The Southeastern Atlantic Coast Of The United States, Kelly R. Johnson
Dissertations, Theses, and Masters Projects
No abstract provided.
Effect On Heartbeat Of Drosophila Melanogaster Of Mutations In The Calcium Channel Encoding Cacophony Gene And Its Interaction With The Rna Helicase Mutant Maleless^Napts, Vanessa Mcgowan
Electronic Theses and Dissertations
There is a lack of information concerning the genetics of heart disease, especially of those due to aberrant pacemaker activity. Drosophila melanogaster is an ideal candidate for research in this area because of its suitability to genetic manipulation and its accessible genetic database. What is most compelling, however, is that the genesis of heartbeat is Drosophila is strikingly similar to that in many other organisms, including mammals. The myogenic heart of DrosophiIa melanogaster is stimulated to contract by a caudal pacemaker, which is regulated by ion channel interactions. A voltage-gated calcium channel of PIQ- or N-type is implicated in the …
Historical Diet Analysis Of Loggerhead (Caretta Caretta) And Kemp's Ridley (Lepidochelys Kempi) Sea Turtles In Virginia, Erin E. Seney
Historical Diet Analysis Of Loggerhead (Caretta Caretta) And Kemp's Ridley (Lepidochelys Kempi) Sea Turtles In Virginia, Erin E. Seney
Dissertations, Theses, and Masters Projects
The Chesapeake Bay and coastal waters of Virginia, U.S.A. serve as foraging grounds for loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempi) sea turtles from approximately May to October each year. Both loggerheads and Kemp’s ridleys are known to feed primarily on benthic invertebrates as juveniles and adults, but specific prey preferences vary between geographic regions. The Virginia Institute of Marine Science Sea Turtle Program has collected diet data and gut samples from stranded and incidentally caught sea turtles in Virginia since 1979. Examination of turtles that stranded in Virginia during the late 1970s and early 1980s indicated that loggerheads …
Biology Of Mated Triploid Crassostrea Ariakensis In Multiple Environments: Gametogenesis, Sex Ratio, Disease Prevalence, And Reversion, Alan J. Erskine
Biology Of Mated Triploid Crassostrea Ariakensis In Multiple Environments: Gametogenesis, Sex Ratio, Disease Prevalence, And Reversion, Alan J. Erskine
Dissertations, Theses, and Masters Projects
No abstract provided.
Synalpheus Shrimp From Carrie Bow Cay, Belize. Systematics, Phylogenetics And Biological Observations (Crustacea: Decapoda: ; Alpheidae), Ruben Rios Gonzalez
Synalpheus Shrimp From Carrie Bow Cay, Belize. Systematics, Phylogenetics And Biological Observations (Crustacea: Decapoda: ; Alpheidae), Ruben Rios Gonzalez
Dissertations, Theses, and Masters Projects
Snapping shrimp in the family Alpheidae are remarkably abundant in coral reef ecosystems worldwide. The second most speciose genus, Synalpheus , includes species usually small and reclusive, and their general morphology is notably uniform, yet the number of species is staggeringly high, as is the intraspecific variability. These features have contributed to a poorly resolved taxonomic status, as evidenced both by recurring lumping and splitting of species and by lack of proper definition of several common species. I examined western Atlantic species of Synalpheus in the large and regionally dominant "Gambarelloides group of species", an informal but widely used guild …
Homing Success Of Migrants Versus Nonmigrants: Do Differences In Spatial Memory Generalize Across Spatial Scales?, Jeffrey T. Keiser
Homing Success Of Migrants Versus Nonmigrants: Do Differences In Spatial Memory Generalize Across Spatial Scales?, Jeffrey T. Keiser
Dissertations, Theses, and Masters Projects
No abstract provided.