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Processes For The Allocation, Reallocation And Governance Of Resource Access In Connection With A Framework For The Future Management Of Fisheries In Western Australia, Government Of Western Australia Department Of Fisheries May 2002

Processes For The Allocation, Reallocation And Governance Of Resource Access In Connection With A Framework For The Future Management Of Fisheries In Western Australia, Government Of Western Australia Department Of Fisheries

Fisheries Management Papers

This paper outlines the issues associated with developing a framework to deal explicitly with the allocation, reallocation and the governance of access to the fisheries resources of Western Australia.


Threshold Evolution In Exotic Populations Of A Polyphenic Beetle, Armin P. Moczek, John Hunt, Douglas J. Emlen, Leigh W. Simmons May 2002

Threshold Evolution In Exotic Populations Of A Polyphenic Beetle, Armin P. Moczek, John Hunt, Douglas J. Emlen, Leigh W. Simmons

Biological Sciences Faculty Publications

Polyphenic development is thought to play an important role in the evolution of phenotypic diversity and morphological novelties, yet the evolution of polyphenisms has rarely been documented in natural populations. Here we compare the morphologies of male dung beetles (Onthophagus taurus; Coleoptera: Scarabaeidae) from populations introduced to Australia and the eastern United States. Males in this species express two alternative morphologies in response to larval feeding conditions. Males encountering favourable conditions grow larger than a threshold body size and develop a pair of horns on their heads, whereas males that encounter poor conditions do not reach this threshold size and …


The Fitness Consequences Of Interspecific Eavesdropping Between Plants, Richard Karban, John L. Maron May 2002

The Fitness Consequences Of Interspecific Eavesdropping Between Plants, Richard Karban, John L. Maron

Biological Sciences Faculty Publications

Although many ecologists have discounted the possibility of communication between plants, recent work demonstrates that wild tobacco plants with experimentally clipped sagebrush neighbors suffer less leaf herbivory than tobacco controls with unclipped neighbors. In this report, we examine the fitness consequences of resistance induced by eavesdropping. Annual tobacco plants with clipped sagebrush neighbors produced more flowers and seed-bearing capsules than plants with unclipped neighbors although these performance measures varied considerably over the five years of the study. Tobacco plants with clipped neighbors also suffered more frost damage than controls in one year. There was no indication that eavesdropping was more …


Patterns And Processes Of Population Differentiation In The Chuckwalla (Sauromalus Obesus) In Southern Nevada, Paul C. Ustach May 2002

Patterns And Processes Of Population Differentiation In The Chuckwalla (Sauromalus Obesus) In Southern Nevada, Paul C. Ustach

Biology

I examined both present-day and historical patterns in the herbivorous desert lizard, Sauromalus obesus (chuckwalla), within the Mojave Desert ecoregion in Nevada. My goal was to determine the process or processes that led to their present-day distribution. I expected to recover distinct haplotypes unique to each mountain range. These unique haplotypes were expected to reveal a pattern of geographic partitioning with sequence divergence among populations increasing as a function of distance. I characterized the distribution of chuckwallas in Nevada by means of a simple model using a geographic information system (GIS). This simple model was used to enhance sampling efficiency …


The Ecology Of Lianas And Their Role In Forests, Stefan A. Schnitzer, Frans Bongers May 2002

The Ecology Of Lianas And Their Role In Forests, Stefan A. Schnitzer, Frans Bongers

Biological Sciences Faculty Research and Publications

Recent studies have demonstrated the increasingly important role of lianas (woody vines) in forest regeneration, species diversity and ecosystem-level processes, particularly in the tropics. Mechanisms responsible for the maintenance of liana species diversity could yield new insights into the maintenance of overall species diversity. Lianas contribute to forest regeneration and competition, not only by competing directly with trees, but also by differentially affecting tree species and thus changing how trees compete among themselves. In addition, they contribute considerably to ecosystem-level processes, such as whole-forest transpiration and carbon sequestration. As the rate of tropical forest disturbance increases, they are likely to …


Analyses Of Diet And Geographic Variation In Leaf-Nosed Snakes, Phyllorhynchus, Stephanie A. Gardner May 2002

Analyses Of Diet And Geographic Variation In Leaf-Nosed Snakes, Phyllorhynchus, Stephanie A. Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study revealed that P. decurtatus primarily eat squamate eggs, and that the diet of P. browni appears to consist entirely of squamate eggs; gecko tails constitute a very small proportion of the diet of P. decurtatus. Feeding in both species occurred throughout their active seasons and both species increased prey consumption in August. The sexes of P. browni, but not P. decurtatus showed different monthly feeding patterns. Desert-of-collection did not affect P. decurtatus monthly feeding patterns. Phyllorhynchus decurtatus collected from the Sonoran Desert and P. browni, which is found only in the Sonoran Desert, showed similar …


Patterns And Processes Of Population Differentiation In The Chuckwalla (Sauromalus Obesus) In Southern Nevada, Paul C. Ustach May 2002

Patterns And Processes Of Population Differentiation In The Chuckwalla (Sauromalus Obesus) In Southern Nevada, Paul C. Ustach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I examined both present-day and historical patterns in the herbivorous desert lizard, Sauromalus obesus (chuckwalla), within the Mojave Desert ecoregion in Nevada. My goal was to determine the process or processes that led to their present-day distribution. I expected to recover distinct haplotypes unique to each mountain range. These unique haplotypes were expected to reveal a pattern of geographic partitioning with sequence divergence among populations increasing as a function of distance. I characterized the distribution of chuckwallas in Nevada by means of a simple model using a geographic information system (GIS). This simple model was used to enhance sampling efficiency …


Patterns Of Avifauna Use Of Constructed Wetlands In The Beaver Creek Wetland Complex, Menifee County, Kentucky, Michael E. Kenawell Apr 2002

Patterns Of Avifauna Use Of Constructed Wetlands In The Beaver Creek Wetland Complex, Menifee County, Kentucky, Michael E. Kenawell

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Michael E. Kenawell on April 16, 2002.


Murine Epidermal Cell Antigen (Skn)-Directed Autoimmunity Induced By Transfer Of Cd4+ T Cells, Susan H. Jackman, Shivaleela Keerthy, Giselle Perry Apr 2002

Murine Epidermal Cell Antigen (Skn)-Directed Autoimmunity Induced By Transfer Of Cd4+ T Cells, Susan H. Jackman, Shivaleela Keerthy, Giselle Perry

Biochemistry and Microbiology

While pathogenic T cells have been identified for several diseases with epithelial cell damage, an autoimmune T cell-mediated response targeted against a known keratinocyte antigen has not been reported. Previously we described an autoimmune response directed to the mouse epidermal cell antigens, Skn. For our murine model, primed Skn-immune lymphocytes are adoptively transferred to recipients, which develop lesions at the site of mild skin trauma. In this study we investigated the nature of the autoimmune component of the Skn response. A time-course study demonstrated a relationship between the number of primed Sknimmune cells injected and the severity of skin lesions …


Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott J. Meiners, Matthew J. Matinkovic Apr 2002

Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott J. Meiners, Matthew J. Matinkovic

Faculty Research & Creative Activity

Forest edges are known to affect plant community composition and habitat use by animals. However, the direct influence of edges in determining patterns of tree regeneration is poorly understood. Survival of and herbivore damage to Quercus ruln-a seedlings were experimentally determined for seedlings planted across a forest--old-field edge gradient. Seedling survival was lowest inside the forest ( 1%), intermediate at the edge (25%) and highest within the old-field portion of the gradient (49%). Deer herbivory decreased with increasing distance into the old field. Seedling survival increased under Rosa multiflora and decreased in plots with mammalian herbivory. Seedling height was significantly …


Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott Meiners, Matthew Matinkovic Apr 2002

Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott Meiners, Matthew Matinkovic

Faculty Research & Creative Activity

Forest edges are known to affect plant community composition and habitat use by animals. However, the direct influence of edges in determining patterns of tree regeneration is poorly understood. Survival of and herbivore damage to Quercus ruln-a seedlings were experimentally determined for seedlings planted across a forest--old-field edge gradient. Seedling survival was lowest inside the forest ( 1%), intermediate at the edge (25%) and highest within the old-field portion of the gradient (49%). Deer herbivory decreased with increasing distance into the old field. Seedling survival increased under Rosa multiflora and decreased in plots with mammalian herbivory. Seedling height was significantly …


The Role Of Glutathione In The Defense Pathway Response Of Arabidopsis Thaliana To The Pathogen Pseudomonas Syringae Pathovar Tomato Dc3000 Avrb, Allison Patrice Mckenna Apr 2002

The Role Of Glutathione In The Defense Pathway Response Of Arabidopsis Thaliana To The Pathogen Pseudomonas Syringae Pathovar Tomato Dc3000 Avrb, Allison Patrice Mckenna

Masters Theses

Inoculation of Arabidopsis thaliana with Pseudomonas syringae pv. tomato DC3000 AvrB (Pst) results in a series of biochemical changes, including an oxidative burst, accumulation of salicylic acid, (de)phosphorylation of proteins, localization of transcription factors to the nucleus and ultimately expression of pathogenesis-related genes. The redox status within plant cells, which is maintained by a cycle of antioxidants that are largely dependent on the reduced form of glutathione (GSH), because of its ability to donate electrons that are necessary to quench reactive oxygen species (ROS). This study focuses on the role of glutathione in the early defense responses of Arabidopsis to …


Determination Of Nuclear Factor-Kappa B Activation In Cultured Renal Epithelial Cells And Cardiac Myocytes Exposed To Cocaine And Morphine, David Angeles Tiangco Apr 2002

Determination Of Nuclear Factor-Kappa B Activation In Cultured Renal Epithelial Cells And Cardiac Myocytes Exposed To Cocaine And Morphine, David Angeles Tiangco

Biological Sciences Theses & Dissertations

Nuclear factor-kappa B (NF-kB) is an important transcription factor that participates in the genetic regulation of inflammation in many tissues. Cocaine and heroin are drugs of abuse associated with renal and cardiac pathology. The purpose of this study was to test the hypothesis that exposure to cocaine or morphine (a metabolite of heroin) would activate NF-kB in renal epithelial cells (COS-7) and cardiac myocytes (H9c2) grown in culture. COS-7 and H9c2 cells were co-transfected with an experimental reporter specific for NF-kB activation and a control reporter with constitutive activity. A dual-luciferase assay was used to determine levels of NF-kB activation …


Serotonin Modulates Oscillations Of The Membrane Potential In Isolated Spinal Neurons From Lampreys, I. V. Batueva, James T. Buchanan, N. P. Veselkin, E. I. Suderevskaya, E. A. Tsvetkov Mar 2002

Serotonin Modulates Oscillations Of The Membrane Potential In Isolated Spinal Neurons From Lampreys, I. V. Batueva, James T. Buchanan, N. P. Veselkin, E. I. Suderevskaya, E. A. Tsvetkov

Biological Sciences Faculty Research and Publications

Studies were performed on spinal neurons from lampreys isolated by an enzymatic/mechanical method using pronase. The effects of 100 µM serotonin (5-HT) on membrane potential oscillations induced by a variety of excitatory amino acids were studied. 5-HT was found to depolarize branched cells (presumptive motoneurons and interneurons) by 2–6 mV without inducing membrane potential oscillations. However, when oscillations were already present because of an excitatory amino acid, 5-HT changed the parameters of these oscillations, increasing the amplitudes of all types of oscillations, increasing the frequency of irregular oscillations, and increasing the duration of the depolarization plateaus accompanied by action potentials. …


Biological Implications Of The Weibull And Gompertz Models Of Aging, Robert Ricklefs, Alex Scheuerlein Feb 2002

Biological Implications Of The Weibull And Gompertz Models Of Aging, Robert Ricklefs, Alex Scheuerlein

Biology Department Faculty Works

Gompertz and Weibull functions imply contrasting biological causes of demographic aging. The terms describing increasing mortality with age are multiplicative and additive, respectively, which could result from an increase in the vulnerability of individuals to extrinsic causes in the Gompertz model and the predominance of intrinsic causes at older ages in the Weibull model. Experiments that manipulate extrinsic mortality can distinguish these biological models. To facilitate analyses of experimental data, we defined a single index for the rate of aging (ω) for the Weibull and Gompertz functions. Each function described the increase in aging-related mortality in simulated ages at death …


A Motor And A Brake: Two Leg Extensor Muscles Acting At The Same Joint Manage Energy Differently In A Running Insect, Anna N. Ahn, Robert J. Full Feb 2002

A Motor And A Brake: Two Leg Extensor Muscles Acting At The Same Joint Manage Energy Differently In A Running Insect, Anna N. Ahn, Robert J. Full

All HMC Faculty Publications and Research

The individual muscles of a multiple muscle group at a given joint are often assumed to function synergistically to share the load during locomotion. We examined two leg extensors of a running cockroach to test the hypothesis that leg muscles within an anatomical muscle group necessarily manage (i.e. produce, store, transmit or absorb) energy similarly during running. Using electromyographic and video motion-analysis techniques, we determined that muscles 177c and 179 are both active during the first half of the stance period during muscle shortening. Using the in vivo strain and stimulation patterns determined during running, we measured muscle power output. …


The Mayfly Newsletter, Peter M. Grant Feb 2002

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.


Shortening Velocity And Myosin Heavy- And Light-Chain Isoform Mrna In Rabbit Arterial Smooth Muscle Cells, Jennifer J. Sherwood, Thomas J. Eddinger Jan 2002

Shortening Velocity And Myosin Heavy- And Light-Chain Isoform Mrna In Rabbit Arterial Smooth Muscle Cells, Jennifer J. Sherwood, Thomas J. Eddinger

Biological Sciences Faculty Research and Publications

In smooth muscle cells (SMCs) isolated from rabbit carotid, femoral, and saphenous arteries, relative myosin isoform mRNA levels were measured in RT-PCR to test for correlations between myosin isoform expression and unloaded shortening velocity. Unloaded shortening velocity and percent smooth muscle myosin heavy chain 2 (SM2) and myosin light chain 17b (MLC17b) mRNA levels were not significantly different in single SMCs isolated from the luminal and adluminal regions of the carotid media. Saphenous artery SMCs shortened significantly faster (P < 0.05) than femoral SMCs and had more SM2 mRNA (P < 0.05) than carotid SMCs and less MLC17b mRNA (P < 0.001) and higher tissue levels of SMB mRNA (P < 0.05) than carotid and femoral SMCs. No correlations were found between percent SM2 and percent MLC17b mRNA levels and unloaded shortening velocity in SMCs from these arteries. …


Effects Of Subchronic Treatment Of Some Plant Growth Regulators On Serum Enzyme Levels In Rats, İsmai̇l Çeli̇k, Hanefi̇ Özbek, Yasi̇n Tülüce Jan 2002

Effects Of Subchronic Treatment Of Some Plant Growth Regulators On Serum Enzyme Levels In Rats, İsmai̇l Çeli̇k, Hanefi̇ Özbek, Yasi̇n Tülüce

Turkish Journal of Biology

The effects of a sublethal concentration of three plant growth regulators (PRGs) on serum enzymes in rats were investigated under laboratory conditions. 100-ppm of PRGs, indoleacetic acid (IAA), indolebutiric acid (IBA) and kinetin were administered orally to 8 rats ad libitum for 3 weeks. The hormon treatments caused different effects on the level of serum alanin aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), amylase and creatine phosphokinase (CPK) in comparison to those of control rats. According to the results, while the levels of LDH and CPK were increased significantly by IBA, the levels of AST, LDH and CPK were …


Effects Of Photoperiod And Temperature On Growth And Reproductive Organ Mass In Adult Male Mongolian Gerbils, Meriones Unguiculatus, Bülent Gündüz Jan 2002

Effects Of Photoperiod And Temperature On Growth And Reproductive Organ Mass In Adult Male Mongolian Gerbils, Meriones Unguiculatus, Bülent Gündüz

Turkish Journal of Biology

Rates of growth and sexual maturation of Mongolian gerbils vary in response to photoperiod. Previous work has shown that the responses of the testes and body weight of juvenile and adult gerbils are influenced not only by the photoperiods but also by other factors. The present work sought to determine if Mongolian gerbils alter body mass, body composition and/or reproductive organ mass in response to different photoperiods and temperatures. Male Mongolian gerbils were raised under long (14L) or short (10L) photoperiods from 26 days of age. Photoperiods did not affect body mass and body length. Temperature affected body mass only …


Changes In The Freshwater Mussel (Bivalvia: Unionidae) Fauna Of The Cuyahoga River, Ohio, Since Late Prehistory, Michael J.S. Tevesz, Louie Rundo, Robert A. Krebs, Brian G. Redmond, Ann S. Dufresne Jan 2002

Changes In The Freshwater Mussel (Bivalvia: Unionidae) Fauna Of The Cuyahoga River, Ohio, Since Late Prehistory, Michael J.S. Tevesz, Louie Rundo, Robert A. Krebs, Brian G. Redmond, Ann S. Dufresne

Biological, Geological, and Environmental Faculty Publications

We provide new information from archaeological samples on the historical freshwater mussel fauna (Mollusca: Bivalvia: Unionoidea) of the Cuyahoga River (South Park site: occupied between ca. A.D. 950 and 1650) and Black River (White Fort site, occupation centered at ca. A.D. 1350), northeast Ohio. Data from these prehi storic sites are compared with information on extant mussel populations of the Cuyahoga River published between 1890 and 2000. The high representation at both archaeological sites of the species Actinonaias ligamentina, Elliptio dilatata, and Ptychobranchus fasciolaris suggests that these were· among the important clean water species in northeast Ohio prior to European …


A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson Jan 2002

A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson

WM Keck Science Faculty Papers

An unusually well preserved skull, mandible, and indisputably associated post-cranial elements of new sloth, Acratocnus (Miocnus), were recovered from a cave in Jaragua National Park, Dominican Republic. The animal died lying in a rimstone pool and was rapidly coated with a thin calcite patina. We have documented a late Wisconsinan age for this specimen by inorganic 14C radiometric dating of the patina, with supporting data on the carbon systematics of the speleothems in this cave. This sloth is described as a new species on the basis of the distinctive morphology and relative size of cranial and mandibular features. We consider …


A Middle Pleistocene Age And Biogeography For The Extinct Rodent Megalomys Curazensis From Curaçao, Netherlands Antilles, Donald A. Mcfarlane, Joyce Lundberg Jan 2002

A Middle Pleistocene Age And Biogeography For The Extinct Rodent Megalomys Curazensis From Curaçao, Netherlands Antilles, Donald A. Mcfarlane, Joyce Lundberg

WM Keck Science Faculty Papers

The extinct oryzomyine rodent Megalomys curazensis has been known from abundant but fragmentary remains on the island of Curaçao since 1959. Here we demonstrate an age of 130 000 to 400 000 years before present based on geomorphological context, and propose a biogeographical model for the genus.


Problems With Developmental Stability In Two Rodent Species From Chornobyl, Taras K. Oleksyk, Michael H. Smith, Sergiy P. Gashchak, James M. Novak, James R. Purdue Jan 2002

Problems With Developmental Stability In Two Rodent Species From Chornobyl, Taras K. Oleksyk, Michael H. Smith, Sergiy P. Gashchak, James M. Novak, James R. Purdue

Faculty Research & Creative Activity

Changes in developmental patterns are some of the most important effects that may be observed at radioactively contaminated sites like those at Chornobyl. Developmental instability may arise from the interactions between an organism's genotype and its environment and be manifested as deviant morphology. Fluctuating asymmetry (FA) is a measure of deviations from the expected bilateral symmetry of the body. Our objective was to test for differences in FA in two rodent species (Apodemus flavicollis and Clethrionomys glareolus) that live in habitats suirounding the failed Chornobyl reactor. Rodents were collected from four different locations (two contaminated and two reference sites), and …


Acoustic Competition In The Gulf Toadfish Opsanus Beta: Acoustic Tagging, Robert F. Thorson, Michael L. Fine Jan 2002

Acoustic Competition In The Gulf Toadfish Opsanus Beta: Acoustic Tagging, Robert F. Thorson, Michael L. Fine

Biology Publications

Nesting male gulf toadfish Opsanus beta produce a boatwhistle advertisement call used in male–male competition and to attract females and an agonistic grunt call. The grunt is a short-duration pulsatile call, and the boatwhistle is a complex call typically consisting of zero to three introductory grunts, a long tonal boop note, and zero to three shorter boops. The beginning of the boop note is also gruntlike. Anomalous boatwhistles contain a short-duration grunt embedded in the tonal portion of the boop or between an introductory grunt and the boop. Embedded grunts have sound-pressure levels and frequency spectra that correspond with those …


Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott J. Meiners, Steward T.A. Pickett, Steven N. Handel Jan 2002

Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott J. Meiners, Steward T.A. Pickett, Steven N. Handel

Faculty Research & Creative Activity

Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest–old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m2 plots in a 90 3 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus …


Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet Jan 2002

Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet

Faculty Publications, Biological Sciences

We studied the changes in heart rate (HR) associated with metabolic rate of incubating and resting adult wandering albatrosses (Diomedea exulans) on the Crozet Islands. Metabolic rates of resting albatrosses fitted with external HR recorders were measured in a metabolic chamber to calibrate the relationship between HR and oxygen consumption (V̇O2) (V̇O2=0.074×HR+0.019, r2=0.567, P<0.001, where V̇O2 is in ml kg–1 min–1 and HR is in beats min–1). Incubating albatrosses were then fitted with HR recorders to estimate energy expenditure of albatrosses within natural field conditions. We also examined the natural variation in HR and the effects of human disturbance on nesting birds by monitoring the changes in HR. Basal HR was positively related to the mass of the individual. The HR of incubating birds corresponded to a metabolic rate that was 1.5-fold (males) and 1.8-fold (females) lower than basal metabolic rate (BMR) measured in this and a previous study. The difference was probably attributable to birds being stressed while they were held in the metabolic chamber or wearing a mask. Thus, previous measurements of metabolic rate under basal conditions or for incubating wandering albatrosses are likely to be overestimates. Combining the relationship between HR and metabolic rate for both sexes, we estimate that wandering albatrosses expend 147 kJ kg–1 day–1 to incubate their eggs. In addition, the cost of incubation was assumed to vary because (i) HR was higher during the day than at night, and (ii) there was an effect of wind chill (<0°C) on basal HR. The presence of humans in the vicinity of the nest or after a band control was shown to increase HR for extended periods (2–3 h), suggesting that energy expenditure was increased as a result of the disturbance. Lastly, males and females reacted differently to handling in terms of HR response: males reacted more strongly than females before handling, whereas females took longer to recover after being handled.


Prey Handling And Diet Of Louisiana Pine Snakes (Pituophis Ruthveni) And Black Pine Snakes (P. Melanoleucus Lodingi), With Comparisons To Other Selected Colubrid Snakes, D. Craig Rudolph, Shirley J. Burgdorf, Richard N. Conner, Christopher S. Collins, Daniel Saenz, Richard R. Schaefer, Toni Trees, C. Michael Duran, Marc Ealy, John G. Himes Jan 2002

Prey Handling And Diet Of Louisiana Pine Snakes (Pituophis Ruthveni) And Black Pine Snakes (P. Melanoleucus Lodingi), With Comparisons To Other Selected Colubrid Snakes, D. Craig Rudolph, Shirley J. Burgdorf, Richard N. Conner, Christopher S. Collins, Daniel Saenz, Richard R. Schaefer, Toni Trees, C. Michael Duran, Marc Ealy, John G. Himes

Faculty Publications

Diet and prey handling behavior were determined for Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi). Louisiana pine snakes prey heavily on Baird's pocket gophers (Geomys breviceps), with which they are sympatric, and exhibit specialized behaviors that facilitate handling this prey species within the confines of burrow systems. Black pine snakes, which are not sympatric with pocket gophers, did not exhibit these specialized behaviors. For comparative purposes, prey handling of P. sayi sayi and Elaphe obsoleta lindheimeri was also examined.


Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger Jan 2002

Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger

Faculty Research & Creative Activity

: The fact that raccoons (Procyon lotor) are an opportunistic omnivore has severely complicated interpreta- tions of contaminant uptake patterns due to the inability to determine the trophic position an individual occupies. Moreover, few studies have examined the relationships between heavy metal bioaccumulation and trophic struc- ture, especially in the terrestrial environment. In this study, the stable isotopes of nitrogen were used to charac- terize the feeding habits of the raccoon at the population level and to determine whether metal burden was relat- ed to trophic feeding structure within a welldefined ecosystem. Raccoon populations were isotopically distinct, and significant positive …


Antimicrobial Activity Of Plants Collected From Serpentine Outcrops In Sri Lanka, Nishanta Rajakaruna, Cory S. Harris, G. H. N. Towers Jan 2002

Antimicrobial Activity Of Plants Collected From Serpentine Outcrops In Sri Lanka, Nishanta Rajakaruna, Cory S. Harris, G. H. N. Towers

Biological Sciences

Thirty-two plant species collected from serpentine (ultramafic) soils in Sri Lanka were screened for antimicrobial properties against three Gram-positive and two Gramnegative bacteria, a non-acid fast bacterium, and the yeast, Candida albicans. Methanol extracts of 29 species belonging to 12 families were active against at least one microorganism. Activity against the Gram-positive and non-acid fast bacteria was common, however, only two taxa, Lantana camara L. (Verbenaceae) and a species of Phyllanthus L. (Euphorbiaceae), were active against the Gram-negative bacterium Pseudomonas aeruginosa. None of the species was active against the other Gram-negative bacterium, Escherichia coli, or C. albicans. Photoactivity was observed …