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Phylogenetic Relationships, Taxonomy, And Evolution Of Host Choice In Diadasia (Hymenoptera: Apoidea), Sedonia D. Sipes May 2001

Phylogenetic Relationships, Taxonomy, And Evolution Of Host Choice In Diadasia (Hymenoptera: Apoidea), Sedonia D. Sipes

Biology

I examined the phylogenetic relationships, taxonomy, and evolution of host choice in Diadasia, a genus of New World bees. Diadasia species are particularly interesting because they are considered pollen specialists. Females of each species are believed to provision their nests with pollen from only a few closely related plant taxa. At the same time, the choice of floral hosts within the genus is diverse, and includes five distantly related plant families: Malvaceae, Onagraceae, Convolvulaceae, Asteraceae, and Cactaceae. To estimate phylogenetic relationships within this group, I sequenced ~ 2 kb of the mitochondrial genes CO I and II and tRNA …


Treefall Gaps And The Maintenance Of Species Diversity In A Tropical Forest, Stefan A. Schnitzer, Walter P. Carson Apr 2001

Treefall Gaps And The Maintenance Of Species Diversity In A Tropical Forest, Stefan A. Schnitzer, Walter P. Carson

Biological Sciences Faculty Research and Publications

The maintenance of species diversity by treefall gaps is a long‐standing paradigm in forest ecology. Gaps are presumed to provide an environment in which tree species of differing competitive abilities partition heterogeneous resources. The empirical evidence to support this paradigm, however, remains scarce, and some recent studies even suggest that gaps do not maintain the diversity of shade‐tolerant species. Although there is evidence that gaps maintain the diversity of pioneer trees, most of this evidence comes from studies that did not make comparisons between gaps and intact forest sites (controls). Further, nearly all studies on the maintenance of diversity by …


Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner Jan 2001

Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner

Turkish Journal of Biology

Rainbow trout (Oncorhynchus mykiss) were fed diets containing three different concentrations of crude protein (56.3%, 51.7% and 45.8%) and digestible energy (21.3, 20.3 and 18.8 MJ/kg), and the effects of dietary protein and energy level on gastric evacuation and return of appetite times were investigated. Gastric evacuation determinations were achieved by slaughtering 8 fish every 6 hours until no residue was found in the cardiac stomach of fish. Return of appetite experiments were conducted by re-feeding groups of trout every 4 or 6 hours following the first feeding. The data obtained from each process was modelled by regression analysis and …


Effects Of Recording Media On Echolocation Data From Broadband Bat Detectors, Ethan P. White, S. D. Gehrt Jan 2001

Effects Of Recording Media On Echolocation Data From Broadband Bat Detectors, Ethan P. White, S. D. Gehrt

Biology Faculty Publications

Bat detectors are an important tool for ecological studies of bats. However, the quality and quantity of data may be affected by the recording devices used to record the output from the detector. We compared recordings of bat activity from audiocassette recorders and computers. Numbers of calls/hour, passes/hour, identifiable passes/hour, and feeding buzzes/hour were similar (all P’s > 0.1) between recording devices. All call characteristics, except for the minimum frequency and characteristic frequency, differed (P < 0.05) between tapes and computers. Species identification with discriminate function analysis was less reliable with tape data than with computer data, particularly when the model built with computer-recorded reference calls was tested with tape-recorded calls. Therefore, we suggest when tape recorders are used for field recording that they also are used to record reference calls.


A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker Jan 2001

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.


The Mayfly Newsletter, Peter M. Grant Dec 2000

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


The Impact Of Lianas On Tree Regeneration In Tropical Forest Canopy Gaps: Evidence For An Alternative Pathway Of Gap‐Phase Regeneration, Stefan A. Schnitzer, James W. Dalling, Walter P. Carson Aug 2000

The Impact Of Lianas On Tree Regeneration In Tropical Forest Canopy Gaps: Evidence For An Alternative Pathway Of Gap‐Phase Regeneration, Stefan A. Schnitzer, James W. Dalling, Walter P. Carson

Biological Sciences Faculty Research and Publications

1 Regeneration in forest canopy gaps is thought to lead invariably to the rapid recruitment and growth of trees and the redevelopment of the canopy. Our observations, however, suggest that an alternate successional pathway is also likely, whereby gap‐phase regeneration is dominated by lianas and stalled in a low‐canopy state for many years. We investigated gap‐phase regeneration in an old‐growth tropical forest on Barro Colorado Island (BCI) in Panama to test the following two hypotheses: (i) many gaps follow a pathway in which they remain at a low canopy height and are dominated by lianas and (ii) the paucity of …


The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors May 2000

The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors

Biological Sciences Faculty Publications

Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong “top-down” control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold …


The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne Jan 2000

The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne

Scholarship and Professional Work - LAS

Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change.


Home Ranges Of Rat Snakes (Colubridae: Elaphe) In Different Habitats, Stephen J. Mullin, William H. N. Gutzke, Gary D. Zenitsky, Robert J. Cooper Jan 2000

Home Ranges Of Rat Snakes (Colubridae: Elaphe) In Different Habitats, Stephen J. Mullin, William H. N. Gutzke, Gary D. Zenitsky, Robert J. Cooper

Faculty Publications

Based on our findings, we suggest that rat snakes represent not only a major predator of kites, but also of other canopy and mid-story nesting species in the southeastern United States. For example, rat snakes are the most dominant snake nest predator of bird nests throughout the Southeast (DeGregorio et al. 2014) and are skilled tree climbers that often occupy arboreal habitats (Jackson 1976, Keller and Heske 2000, Sperry et al. 2009), particularly in bottomland forests (Mullin et al. 2000, Carfagno and Weatherhead 2009). Thus, the role of rat snakes as predators of nests above the understory is likely underappreciated …


Studying The Expression Of A Novel Microsatellite Mrna In Chironomous Riparius, Mina Ranzurmal Jan 2000

Studying The Expression Of A Novel Microsatellite Mrna In Chironomous Riparius, Mina Ranzurmal

Seton Hall University Dissertations and Theses (ETDs)

The expression of a unique mRNA containing a microsatellite sequence was studied in C. riparius using differential display. First, the rnicrosatellite fragment was sequenced using Sanger's Sequencing method. The microsatellite cDNA contained 11 "ACA" repeats, 12 "AC" repeats, and 5 "CTC" repeats. Second, the affects of cadmium and heat shock on rnicrosatellite mRNA expression were studied. In cadmium experiments, larvae were exposed to low cadmium concentrations (0, 0.04, 0.4, and 4.0 mM) for 24 and 48 h and high cadmium concentrations (0, 1.0, 2.0, 4.0, 8.0, and 16.0 mM) for 48 h. The effects of cadmium on fed larvae at …


The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon Jan 2000

The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon

College of Graduate Studies: Theses & Dissertations (1964–2006)

Broxton Rocks Nature Preserve, a 1,233-hectare preserve containing late Pleistocene sandstone (Altamaha grit) outcrops of various sizes and topographies in a conifer-dominated loblolly pine - hardwood forest, represents a unique habitat to the coastal plain of Georgia. Using modified pitfall traps, I sampled arthropods in four subhabitats (bare rock, lichens, ecotone, wiregrass) at Broxton Rocks between January and November 1999. A total of 312,006 arthropods belonging to four classes (Arachnida, Diplopoda, Chilopoda, Insecta) represented by 24 orders was trapped. The numbers of arthropods varied among habitat types, and over the collection dates (P


The Effects Of Low Ph On Sunfish Assemblages In Southeast Georgia, William Boyd Tate Jan 2000

The Effects Of Low Ph On Sunfish Assemblages In Southeast Georgia, William Boyd Tate

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.


The Biological Flora Of Coastal Dunes And Wetlands. Ipomoea Imperati (Vahl) Griseb., Robert I. Lonard, Frank W. Judd Jul 1999

The Biological Flora Of Coastal Dunes And Wetlands. Ipomoea Imperati (Vahl) Griseb., Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Beach morning glory, Ipomoea imperati (Vahl) Griseb. = I. stolonifera (Cirillo) Gmelin is a pantropical, prostrate vine that is an important pioneer species in the backshore of coastal beaches of six continents and many islands. The landward distribution of beach morning glory is influenced by dispersal and competition, and its seaward distribution is determined by the physical environment acting through movement of seeds away from the water and high seedling mortality in the backshore. It is occasionally found in disturbed sites on barrier islands well inland from the shore. Beach morning glory tolerates low levels of soil nutrients, sand scouring, …


The Mayfly Newsletter, Peter M. Grant Jun 1999

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Analysis Of Intraguild Predation With A Consideration Of Adaptive Foraging, Toshinori Okuyama May 1999

Analysis Of Intraguild Predation With A Consideration Of Adaptive Foraging, Toshinori Okuyama

School of Biological Sciences: Dissertations, Theses, and Student Research

Identification of interactive units in food webs is particularly important in population and community ecology. Intraguild predation has gained much attention recently with the recognition of its prevalence in the field, although its significance has not been fully studied. Nature contains much more complex interactions than a simple food chain. Yet, much theory still focuses on the trophic levels connected in a single linear chain. In this thesis, I study intraguild predation including the consideration of animal behavior whose importance is also often neglected in population and community ecology.

First, the concepts of intraguild predation and animal behavior are introduced. …


Possible Predation Scars On Rectithyris Subdepressa (Stoliczka, 1872), Late Cretaceous (Maastrichtian) Kallankurichi Fm., India, Rex Alan Hanger, Rama Krishnaswamy Apr 1999

Possible Predation Scars On Rectithyris Subdepressa (Stoliczka, 1872), Late Cretaceous (Maastrichtian) Kallankurichi Fm., India, Rex Alan Hanger, Rama Krishnaswamy

Virginia Journal of Science

A single specimen of the terebratulid brachiopod, Rectithyris subdepressa (Stoliczka, 1872) from the Late Cretaceous (Maastrichtian) Kallankurichi Fonnation of southern India was found with durophagous predation traces. This occurrence is significant as it is possibly the first documentation of elasmobranch shark predation on brachiopods from the Mesozoic.


The Ecology And Vocalisations Of Banded Ground-Cuckoo Neomorphus Radiolosus, Bernabé López-Lanús, Karl S. Berg, Ralf Strewe, Paul G. W. Salaman Jan 1999

The Ecology And Vocalisations Of Banded Ground-Cuckoo Neomorphus Radiolosus, Bernabé López-Lanús, Karl S. Berg, Ralf Strewe, Paul G. W. Salaman

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

El Cuco-Hormiguero Franjeado Neomorphus radiolosus es un ave rara, con problemas de conservación y cuya información sobre comportamiento y biología es deficiente. Cualquier dato adicional en este aspecto representa un instrumento importante para su conservación. Presentamos nuevos datos sobre su compartamiento en base a individuos observados en la Estación Biológica Jatun Sacha Bilsa, Esmeraldas, Ecuador, y la Reserva El Pangan, Nariño, Colombia.


Is Population Genetics Mired In The Past?, Andrew J. Bohonak, Neil Davies, George K. Roderick, Francis X. Villablanca Sep 1998

Is Population Genetics Mired In The Past?, Andrew J. Bohonak, Neil Davies, George K. Roderick, Francis X. Villablanca

Biological Sciences

No abstract provided.


The Reproductive Ecology, Demography, And Population Genetic Structure Of Arctomecon Californica Torrey & Fremont (Papaveraceae) In Fragmented And Unfragmented Habitat, Laura L. Hickerson May 1998

The Reproductive Ecology, Demography, And Population Genetic Structure Of Arctomecon Californica Torrey & Fremont (Papaveraceae) In Fragmented And Unfragmented Habitat, Laura L. Hickerson

Biology

Arctomecon californica (the Las Vegas bearpoppy) is endemic to gypsum outcrops of the northern Mojave Desert. Native habitat of this plant in the Las Vegas Valley has been severely fragmented, while relatively undisturbed, unfragmented habitat still exists in the Lake Mead National Recreation Area. I studied the reproductive ecology and population genetic structure of this rare plant. Comparisons were then drawn between fragmented and unfragmented habitat. Arctomecon californica flowers are mostly self-incompatible, and require a pollen vector for successful seed production. Evidence of pollinator limitation was found in both habitat types, but plants in fragmented habitat were much less successful …


Ecology And Natural History Of The Cow Knob Salamander, Plethodon Punctatus Highton, In West Virginia, Robert B. Tucker Jan 1998

Ecology And Natural History Of The Cow Knob Salamander, Plethodon Punctatus Highton, In West Virginia, Robert B. Tucker

Theses, Dissertations and Capstones

Very little has been written on the ecology and natural history of the Cow Knob salamander, Plethodon punctatus Highton, since it was described by Highton (1971). Plethodon punctatus is known only from the higher elevations of Great North (above 2,800 ft) and Shenandoah (above 3,000 ft.) Mountains in Virginia and West Virginia (Highton, 1972; Conant and Collins, 1991). The type locality is Cow Knob, Pendleton County, West Virginia. Plethodon punctatus is a large (up to 75 mm snout-to-vent length) dorso-ventrally flattened salamander with creamish iridiophore spots on the back and sides, webbed feet for a fossorial lifestyle, and large …


Life History, Ecology, And Low Ph Tolerance Of The Freshwater Prawn, Palaemonetes Kadiakensis Rathbun, In A Mitigated Wetland Of The Green Bottom Wildlife Management Area, West Virginia, Jennifer Ann Aderman Jan 1998

Life History, Ecology, And Low Ph Tolerance Of The Freshwater Prawn, Palaemonetes Kadiakensis Rathbun, In A Mitigated Wetland Of The Green Bottom Wildlife Management Area, West Virginia, Jennifer Ann Aderman

Theses, Dissertations and Capstones

An ecological life history study of the freshwater prawn Palaemonetes kadiakensis was conducted at the mitigated wetland of the Green Bottom Wildlife management Area (GBWMA). Monthly samples were collected from November 1996 through November 1997. In addition, weekly samples were collected from May through November for growth and reproductive analysis. Monthly samples yielded 520 prawns. Palaemonetes kadiakensis had a one-year life cycle, with all adults dying by September. Males averaged 23.82 mm (range = 14.15 to 36.75 mm) and females averaged 26.78mm (range = 15.06 to 38.60 mm) in length. Males averaged 0.087g (range = 0.014to 0.293 g) and females …


Terminal Restriction Fragment Patterns (Trfps), A Rapid, Pcr-Based Method For The Comparison Of Complex Bacterial Communities, Brian G. Clement, Lucia E. Kehl, Kristin L. Debord, Christopher L. Kitts Jan 1998

Terminal Restriction Fragment Patterns (Trfps), A Rapid, Pcr-Based Method For The Comparison Of Complex Bacterial Communities, Brian G. Clement, Lucia E. Kehl, Kristin L. Debord, Christopher L. Kitts

Biological Sciences

Microbial populations in complex environmental samples are difficult to characterize; current techniques are incomplete and time consuming. We investigated a polymerase chain reaction (PCR)-based method for rapidly comparing bacterial communities independent of culture or cloning. Community 16S rRNA genes were amplified and fluorescently labeled by PCR. The labeled products were digested by a restriction enzyme and the labeled, terminal restriction fragments (TRFs) were separated by electrophoresis and detected by laser-induced fluorescence on an automated gene sequencer. PCR parameters were optimized using an in vitro model community of known organisms. Community comparisons were made between deer fecal pellets, petroleum hydrocarbon-contaminated sands …


Management Of The Houtman Abrolhos System, Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia Dec 1997

Management Of The Houtman Abrolhos System, Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia

Fisheries Management Papers

In November 1995 Cabinet resolved that the Minister for Fisheries would establish the Abrolhos Islands Management Advisory Committee (AIMAC) pursuant to Section 42 of the Fish Resources Management Act 1994. The role of AIMAC is to advise the Minister for Fisheries about the management of the Abrolhos Islands and the adjoining State Territorial Waters, as detailed in Section 2.2.3.1 of this report. The AIMAC has overseen the preparation of this report on behalf of the Minister for Fisheries. This draft report contains a brief description of the Abrolhos System and its special values. It also states goals and objectives for …


The Mayfly Newsletter, Peter M. Grant Dec 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley Oct 1997

Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley

Faculty and Staff Publications – Milner Library

Conservation biology is a multidisciplinary subject of recent origins. Analysis of cited monographs from the journal Conservation Biology resulted in a list of 47 monographs which were heavily cited for this discipline. Over half of these were from related disciplines such as ecology, genetics, evolution, population biology, statistics, and natural resource management.


The Mayfly Newsletter, Peter M. Grant Jun 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea May 1997

The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea

Dissertations and Theses

To protect and manage Pacific Northwest salmonid stocks, sound management programs must be developed that incorporate knowledge of the ecological processes critical to their survival. One such process is the nutrient dynamic in headwater spawning streams. It is essential that we understand the trophic relationships among the spawners, the I to 3 year-old juveniles, the invertebrates, and the primary producers in these streams.

The hypothesis that I tested is that photoautotrophic production increases due to the decomposition of salmon carcasses. Increased primary production would stimulate the production of invertebrates which are an important food resource of juvenile salmonid species. The …


The Role Of Alfalfa Weevil Larvae As Prey In Adult Maintenance And Reproduction By Two Ladybird Beetle Species, Douglas R. Richards May 1997

The Role Of Alfalfa Weevil Larvae As Prey In Adult Maintenance And Reproduction By Two Ladybird Beetle Species, Douglas R. Richards

Biology

Ladybird beetles (Coccinella spp.) are important predators of pea aphids (Acyrthosiphon pisum) in alfalfa. Adult ladybird beetles also consume alternative foods such as alfalfa weevil larvae (Hypera postica) and nectar. I compared egg production and ovariole condition of Coccinella septempunctata (an Old World species introduced to North America) and Coccinella transversoguttata (an indigenous North American species) that were maintained on diets of pea aphids, alfalfa weevil larvae, sugar water ("artificial nectar"), or various combinations of these foods. In the first experiment, gravid females of both species continued to lay many eggs and had large ovarioles …


The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper May 1997

The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biogeographic patterns of animals are shaped by biotic interactions, such as competition, and by abiotic factors, such as climate. Mountain Chickadees (Parus gambeli) and Juniper Titmice (Parus ridgway) are permanent residents of regions of western North America and are ecologically similar, but have different northern range limits. l measured several physiological variables, including basal metabolic rate (BMR), peak metabolic rate (PMR = maximal thermogenic capacity), metabolic response to varying environmental temperature (MRT), evaporative water loss (EWL), and daily energy expenditure (DEE) for summer-and winter-acclimatized Mountain Chickadees and Juniper Titmice to determine if seasonal and interspecific variation in cold tolerance and …