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Ecology and Evolutionary Biology

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Articles 16381 - 16410 of 19704

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Seasonal Patterns Of Photosynthesis In Douglas Fir Seedlings During The Third And Fourth Year Of Exposure To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey May 2001

Seasonal Patterns Of Photosynthesis In Douglas Fir Seedlings During The Third And Fourth Year Of Exposure To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

The interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 p.p.m.) CO2 or ambient +200 p.p.m. CO2, and either ambient temperature or ambient +4 °C. Light-saturated net photosynthetic rates were measured approximately monthly over a 21 month period. Elevated CO2 increased net photosynthetic rates by an average of 21% across temperature treatments during both the 1996 hydrologic year, the third year of exposure, and the 1997 hydrologic year. Elevated …


Natural History And Roosting Ecology Of The Eastern Pipistrelle, Pipistrellus Subflavus, Jacques Pierre Veilleux May 2001

Natural History And Roosting Ecology Of The Eastern Pipistrelle, Pipistrellus Subflavus, Jacques Pierre Veilleux

All-Inclusive List of Electronic Theses and Dissertations

A study concerning the natural history and roosting ecology of the eastern pipistrelle, Pipistrellus subtlavus, was conducted from 1997 to 2000, in southern Vigo County, Indiana. 111 Females began forming pre-maternity colonies during early May, and parturition began during late June. Pre-maternity colonies averaged 3.7 ± 1.9 individuals, and maternity colonies averaged 4.4 ± 2.4 individuals. Young pipistrelles first became volant during the third and fourth weeks of July. Pipistrelles were located in 59 roost trees. All roosts were located in foliage, either in clusters of dead leaves (n = 40) or in live foliage (n = 19). Oaks (Ouercus …


An Ethical Framework For Interpreting The United States Endangered Species Act, Cathryn M. Elgin May 2001

An Ethical Framework For Interpreting The United States Endangered Species Act, Cathryn M. Elgin

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study I argue that a holistic approach is better than an individualistic approach for interpreting the United States Endangered Species Act (ESA). I propose that the use of a holistic ethical framework, based on fundamental environmental philosophy, is better in that it more effectively fulfills the ESA's goals of species and ecosystem conservation. Holistic ethics is based on concern for a community as a whole, while individualistic ethics is based on concern for the individual. A holistic approach, I argue, is more beneficial to nature than is an individualistic approach or other non-holistic approaches. I set up basic …


Patterns Of Avian Productivity Indices At Santa Ana National Wildlife Refuge (1995–1999), Tina Louise Gallegos May 2001

Patterns Of Avian Productivity Indices At Santa Ana National Wildlife Refuge (1995–1999), Tina Louise Gallegos

Theses and Dissertations - UTB/UTPA

I examined demographic parameters at Santa Ana National Wildlife Refuge, 1995–1999 utilizing Monitoring Avian Productivity and Survivorship protocol. The Olive Sparrow was the species most frequently captured. The capture rate of adult and young birds remained fairly steady over the years and no significant linear trends were observed. Productivity was highest in 1997, which influenced the number of adults captured in 1998, and was significantly related to annual rainfall. Mean total capture rates were higher at the Highland station than the Resaca station. Demographic comparisons between mist nets and point counts were variable, suggesting that both sampling techniques have their …


The Taxonomic Rank Of Spizella Taverneri: A Response To Mayr And Johnson, John Klicka, Robert M. Zink, Jon C. Barlow, W. Bruce Mcgillivray, Terry J. Doyle May 2001

The Taxonomic Rank Of Spizella Taverneri: A Response To Mayr And Johnson, John Klicka, Robert M. Zink, Jon C. Barlow, W. Bruce Mcgillivray, Terry J. Doyle

Ornithology Program (HRC)

Mayr and Johnson suggest that Spizella taverneri should be a subspecies of the biological species S. breweri, because it is possibly not reproductively isolated. We originally concluded that evidence from mitochondrial DNA sequences, habitat preferences, timing of breeding, vocalizations, and morphology supported the recognition of S. taverneri as a phylogenetic and biological species. Nothing in the commentary by Mayr and Johnson causes us to change that conclusion. We believe that it is probable that these two allopatric taxa are isolated. Contrary to Mayr and Johnson, we believe that more information is given by ranking S. taverneri as a species, because …


Attitudes And Practices About Weight, Weight Management, And The Association Of These Factors With The Development Of Chronic Disease In A Convenience Sample Of Dietetics Students, Karah Lynnette Lindbergh May 2001

Attitudes And Practices About Weight, Weight Management, And The Association Of These Factors With The Development Of Chronic Disease In A Convenience Sample Of Dietetics Students, Karah Lynnette Lindbergh

Honors Capstones

No abstract provided.


Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham May 2001

Trophic Cascades, Nutrients, And Lake Productivity: Whole-Lake Experiments, Stephen R. Carpenter, Jonathan J. Cole, James R. Hodgson, James F. Kitchell, Michael L. Pace, Darren Bade, Kathryn L. Cottingham

Dartmouth Scholarship

Responses of zooplankton, pelagic primary producers, planktonic bacteria, and CO2 exchange with the atmosphere were measured in four lakes with contrasting food webs under a range of nutrient enrichments during a seven-year period. Prior to enrichment, food webs were manipulated to create contrasts between piscivore dominance and planktivore dominance. Nutrient enrichments of inorganic nitrogen and phosphorus exhibited ratios of N:P > 17:1, by atoms, to maintain P limitation. An unmanipulated reference lake, Paul Lake, revealed baseline variability but showed no trends that could confound the interpretation of changes in the nearby manipulated lakes. Herbivorous zooplankton of West Long Lake (piscivorous fishes) …


Morphometric Evaluation Of The Whitefish Complex In Bear Lake, Utah/Idaho, Alan Ward May 2001

Morphometric Evaluation Of The Whitefish Complex In Bear Lake, Utah/Idaho, Alan Ward

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whitefish populations around the world have long been difficult to categorize taxonomically. The whitefish of Bear Lake, Utah/Idaho are no exception. There are three recognized species of Prosopium that are endemic to the lake. Two of these species, Prosopium spilonotus and Prosopium abyssicota, have previously been indistinguishable outside of spawning times. Previous studies have proposed additional taxa within P. spi/onotus to further complicate the identification among these taxa.

Morphological characteristics were quantified on wild whitefish from Bear Lake, as well as from progeny reared in the laboratory from the wild adult fish. The purported taxa were separated in the field …


Energy, Fractal Movement Patterns, And Scale-Dependent Habitat Relationships Of Urban And Rural Mule Deer, Mark F. Mcclure May 2001

Energy, Fractal Movement Patterns, And Scale-Dependent Habitat Relationships Of Urban And Rural Mule Deer, Mark F. Mcclure

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the behaviors, movement dynamics, habitat relationships, and population characteristics of Rocky Mountain mule deer (Odocoileus hemionus) using urban and rural winter ranges in Cache Valley, Utah, from January 1994 to February 1998. There were 2 goals to my research endeavors. The first was to assess how and why the behaviors and demographic characteristics of urban deer differed from those of rural deer. The second was to assess the scale-dependent responses to habitat and the scale-dependent patterns of habitat use by deer living in each area. To accomplish the first goal, I compared the prevalence of migration, the spatial …


Ecology Of Treeline Whitebark Pine (Pinus Albicaulis) Populations In Central Idaho: Successional Status, Recruitment, And Mortality, And A Spring Temperature Reconstruction From Whitebark Pine Tree Rings, Dana Lee Perkins May 2001

Ecology Of Treeline Whitebark Pine (Pinus Albicaulis) Populations In Central Idaho: Successional Status, Recruitment, And Mortality, And A Spring Temperature Reconstruction From Whitebark Pine Tree Rings, Dana Lee Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated the successional status of treeline whitebark pine (Pinus albicaulis) populations on 14 stands in central Idaho and used empirical statistical models to determine the principal factors affecting recruitment and mortality. The longest lived whitebark pines from four additional high-elevation sites were used to develop a tree-ring chronology to reconstruct over 1,000 years of average April-May temperature.

The assessment of stand structures using size-frequency distributions generally provides evidence that treeline whitebark pine populations are currently self-sustaining in areas of low to nonexistent incidence of white pine blister rust (Cronartium ribicola). However the presence of …


Effectiveness Of Earthen Escape Ramps In Reducing Big Game Mortality In Utah, Mary L. Hammer May 2001

Effectiveness Of Earthen Escape Ramps In Reducing Big Game Mortality In Utah, Mary L. Hammer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One-way escape gates and earthen escape ramps are structures used to enable deer to exit the highway right-of-way along fenced roads. I compared the use of one-way escape gates and earthen escape ramps by mule deer on two highways in Utah to determine if deer exhibited a preference for either structure. Results showed that earthen escape ramps were used by mule deer 8-11 times more frequently than one-way gates. Highway mortality data suggest that the installation of the escape ramps likely reduced mortality of mule deer in both study locations, because we could not attribute reductions in mortality to decreased …


Intensification In A Risky Environment: The Case Of Improving Private Grazing Land For Beef Production In Utah, Louise D. Sainsbury May 2001

Intensification In A Risky Environment: The Case Of Improving Private Grazing Land For Beef Production In Utah, Louise D. Sainsbury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Utah ranchers commonly face risks to their livelihoods. The objective of this work was to determine if ranchers could make profitable improvements to private land forage given the combined threat of low beef prices, drought, and possible loss of public grazing.

We used linear programming (LINDO) to identify the most profitable solutions for private land investment with an 11-year simulation. Operations were divided into small, medium, and large size classes. Various forage improvements and public permits were options. Two phases of a beef price cycle (peak and trough) and 2 precipitation patterns (wet and drought) were combined as joint favorable …


Darwin Remembers: Recollections Of A Life's Journey, Floyd Sandford Apr 2001

Darwin Remembers: Recollections Of A Life's Journey, Floyd Sandford

Iowa Academy of Science Documents

A program of the performance of Darwin Remembers by Floyd Sandford, presented at the 113th (2001) Annual Meeting of the Iowa Academy of Science. Includes a short biography of Charles Darwin, and a listing of the books and monographs of Charles Darwin.


Draft Plan Of Management For The Cottesloe Reef Proposed Fish Habitat Protection Area., Fisheries Western Australia Apr 2001

Draft Plan Of Management For The Cottesloe Reef Proposed Fish Habitat Protection Area., Fisheries Western Australia

Fisheries Management Papers

The aim of this management plan is to promote and encourage the protection and rehabilitation of the aquatic habitat at Cottesloe Reef and to involve the community in its management.


Determining Differences In The Spatial Distribution Of Forest Structure On The Kaibab Plateau: Implications For Forest Management And The Northern Goshawk, Ryan S. Miller Apr 2001

Determining Differences In The Spatial Distribution Of Forest Structure On The Kaibab Plateau: Implications For Forest Management And The Northern Goshawk, Ryan S. Miller

Other Publications in Wildlife Management

The Kaibab Plateau, in North Central Arizona, has undergone extensive change in the last 100 years due to land management practices such as logging, road building, and fire suppression. The northern goshawk (Accipiter gentilis) has been a center of controversy, due to the potential effects of silvicultural practices on goshawk breeding habitat (Reynolds-1983, Bloom et al 1986, Kennedy 1989, Crocker-Bedford 1990). Current and past research efforts on the Kaibab Plateau have mapped Goshawk nesting territories and temporal change in nesting behavior and success. However, these research efforts have not determined how long-term spatial changes in land-use activities that have influenced …


The Evolution Of Irrationality, Owen D. Jones Apr 2001

The Evolution Of Irrationality, Owen D. Jones

Vanderbilt Law School Faculty Publications

The place of the rational actor model in the analysis of individual and social behavior relevant to law remains unresolved. In recent years, scholars have sought frameworks to explain: a) disjunctions between seemingly rational behavior and seemingly irrational behavior; b) the origins of and influences on law-relevant preferences, and c) the nonrandom development of norms. This Article explains two components of an evolutionary framework that, building from accessible insights of behavioral biology, can encompass all three. The components are: "time-shifted rationality" and "the law of law's leverage."


The Implications Of The Target-Area Hypothesis On The Population Dynamics Of The Spotted Spiny Lobster, Panulirus Guttatus, Denice N. Robertson Apr 2001

The Implications Of The Target-Area Hypothesis On The Population Dynamics Of The Spotted Spiny Lobster, Panulirus Guttatus, Denice N. Robertson

Biological Sciences Theses & Dissertations

The target-area hypothesis, based on the theory of island biogeography, predicts that larger islands are more effective at intercepting passive immigrants. Most marine invertebrates have meroplanktonic larvae and open population dynamics, so immigration to populations in isolated benthic habitats is primarily by pelagic larval recruits. Thus, recruitment to isolated habitat “islands” may be more continuous and predictable on large islands than on small ones. Consequently, populations on large islands should not only be larger than those on small islands, but should also have more evenly distributed size structures. These differences in size structure among populations in isolated habitats of differing …


In Support Of A Rationally Managed Fishery: Age And Growth In Patagonian Toothfish (Dissostichus Eleginoides), Julian R. Ashford Apr 2001

In Support Of A Rationally Managed Fishery: Age And Growth In Patagonian Toothfish (Dissostichus Eleginoides), Julian R. Ashford

Biological Sciences Theses & Dissertations

Patagonian toothfish (Dissostichus eleginoides) occur on the continental shelves and shelf breaks of southern South America and the Southern Ocean. Stock structure, critical to good fisheries management, can be inferred from growth differences between areas, but available growth data are compromised by inconsistencies in age estimation methods, sampling and sample sizes, and techniques used to derive estimates. I asked the scientific question: how is growth in Patagonian toothfish structured spatially within the Southern Ocean? I developed a multi-stage randomized design to sample fish caught by commercial longline, and an age estimation methodology. Because toothfish are difficult to age, …


The Effect Of Nitrogen Fertilization On Short-Term Fine Root Dynamics In A Barrier Island Dune Community, John Walter Hutton Apr 2001

The Effect Of Nitrogen Fertilization On Short-Term Fine Root Dynamics In A Barrier Island Dune Community, John Walter Hutton

Biological Sciences Theses & Dissertations

Fine root dynamics are an important yet poorly understood component of terrestrial ecosystems. In recent years a number of researchers have focused on fine root dynamics; their work has looked at patterns across one or multiple growing seasons on a scale of monthly measures. The purpose of this study was to add to the overall understanding by looking at fine root dynamics on a shorter temporal scale. Minirhizotron observation tubes were used to assess the effect of nitrogen fertilization on short-term fine root dynamics in a nutrient limited, barrier island dune system. Root length elongation and mortality rates followed expected …


A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio Apr 2001

A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio

Biological Sciences Theses & Dissertations

Lake Prince and the Western Branch Reservoir are two eutrophic bodies of water located in Suffolk, Virginia. Lake Prince and its two small tributaries join the Western branch via a constructed spillway. This lake system is a source of water for the surrounding municipalities, and a recreational area for community citizens. In the past, these bodies of water had repeated incidents of low oxygen and nuisance algal blooms, particularly cyanobacteria species. As a result aerators have been installed in the main body of both Lake Prince and the Western Branch Reservoir. In addition, a pipeline has been installed from North …


Seasonal Phytoplankton Assemblages Of Five Ephemeral Ponds In York County, Virginia, Michelle R. Kokolis Apr 2001

Seasonal Phytoplankton Assemblages Of Five Ephemeral Ponds In York County, Virginia, Michelle R. Kokolis

Biological Sciences Theses & Dissertations

Five ephemeral ponds were identified in and around the Grafton Ponds Natural Area Preserve, approximately 56 km north of the City of Norfolk, Virginia. These ponds, which are filled seasonally by precipitation and groundwater discharge, range from 0.1 ha to 2 ha in size and from 4 cm to 3 meters in depth. Ponds for the study were chosen based on variations in their size, depth, basin cover material, canopy openness, and historical inundation period. The purpose of this study is to relate differences in the phytoplankton assemblages to the physical and chemical characteristics of the ponds. All five ponds …


Effects Of Human Disturbances On The Behavior Of Dabbling Ducks, Melissa Lynn Pease Apr 2001

Effects Of Human Disturbances On The Behavior Of Dabbling Ducks, Melissa Lynn Pease

Biological Sciences Theses & Dissertations

Disturbance of wintering and migrating birds by human activities can cause birds to expend energy in avoidance of humans and reduces the time available for resting and feeding at a time in the annual cycle when fat deposition and energy conservation are important. Also, human disturbances can effectively cause habitat loss by displacing birds from feeding or resting habitat. Managers of natural resources are increasingly faced with decisions about the types and amounts of public use that should be allowed without lowering the value of the resource for wildlife. In order for managers to make decisions about how to minimize …


Final Plan Of Management For The Lancelin Island Lagoon Fish Habitat Protection Area., Fisheries Western Australia, Australian Marine Conservation Society Friends Of Lancelin Island. Mar 2001

Final Plan Of Management For The Lancelin Island Lagoon Fish Habitat Protection Area., Fisheries Western Australia, Australian Marine Conservation Society Friends Of Lancelin Island.

Fisheries Management Papers

The Lancelin Island Lagoon is a small area of reef habitat on the western side of Lancelin Island and a popular snorkelling and diving destination. Water depth ranges from less than 0.3 m on the intertidal reefs to less than 3 m on the sand or seagrass-covered bottom. The area has a diverse array of benthic marine habitat. During a marine survey of the area, over 200 flora and fauna species were positively identified, with many more remaining unidentified due to the diversity of species supported in this marine environment. The survey, which was facilitated by direct observations and photographs, …


The Prairie Naturalist Volume 33, No.1 March 2001 Mar 2001

The Prairie Naturalist Volume 33, No.1 March 2001

The Prairie Naturalist

VEGETATION STRUCTURE AND INVERTEBRATE BIOMASS OF CONVENTIONAL AND SUSTAINABLE SORGHUM FIELDS IN KANSAS ▪ R. J. Robel and C Xiong

MONTHLY OPEN-WATER BOTTOM TRAWLING AT TWO SOUTH DAKOTA LAKES ▪ B. G. Blackwell and M. L. Brown

WINTER SURVIVAL AND HOME RANGE OF FEMALE RING-NECKED PHEASANT IN RELATION TO FOOD' PLOTS ▪ A E. Gabbert, J. R. Purvis, L. D. Flake, and A P. Leif

THIRD BREEDING RECORD OF BLUE GROSBEAK IN NORTH DAKOTA ▪ K. H. Haas and C A Haas

EVIDENCE OF AMERICAN WOODCOCK NESTING IN SOUTHEASTERN NORTH DAKOTA ▪ F. Y Sargeant and G. A Sargeant

BOOK …


A Common Pattern Of Somite Cell Rotation In Three Species Of Pipidae, Shou-Yuan Fan, Rafael O. De Sá, Gary P. Radice Mar 2001

A Common Pattern Of Somite Cell Rotation In Three Species Of Pipidae, Shou-Yuan Fan, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

During amphibian somitogenesis, presumptive myotome cells change shape from round or polygonal to elongated and aligned parallel to the notochord (for reviews see Radice, et al., 1989; Keller, 2000). Although the final orientation of myotomal cells is always axial, the movements that achieve this final arrangement can differ greatly between species. The simplest movement is that seen in Bombina variegata, Pelobates fuscus, and Bufo bufo (Brustis et al., 1976; Brustis, 1979; Kielbowna, 1981 ). In these anurans, after segmentation myotomal cells simply elongate along the embryo’s anteroposterior axis. The urodeles Ambystoma mexicanum and Pleurodeles waltl have a very different pattern; …


Social Play Behaviour: Cooperation, Fairness, Trust, And The Evolution Of Morality, Marc Bekoff Feb 2001

Social Play Behaviour: Cooperation, Fairness, Trust, And The Evolution Of Morality, Marc Bekoff

Ethology Collection

No abstract provided.


Sustainable Tourism Plan For The Houtman Abrolhos Islands, Fisheries Western Australia Feb 2001

Sustainable Tourism Plan For The Houtman Abrolhos Islands, Fisheries Western Australia

Fisheries Management Papers

The Abrolhos coral reefs are the southernmost living reefs in the Indian Ocean. They have a unique assemblage of tropical species of fish, reef corals and other invertebrates, which live in close association with temperate species, particularly of algae, and species endemic to Western Australia. The Abrolhos is the centre of the fishery for the commercially valuable western rock lobster (Panulirus cygnus). Terrestrial flora and fauna of the Abrolhos are relict and provide important reference areas on ecological interactions. Virtually all the islands of the Abrolhos archipelago have sea bird nesting and breeding areas, and populations of some species of …


Life-History Evolution In Guppies. Vii. The Comparative Ecology Of High- And Low-Predation Environments, David Reznick, Mark J. Butler Iv, Helen Rodd Feb 2001

Life-History Evolution In Guppies. Vii. The Comparative Ecology Of High- And Low-Predation Environments, David Reznick, Mark J. Butler Iv, Helen Rodd

Biological Sciences Faculty Publications

Prior research has demonstrated a strong association between the species of predators that co-occur with guppies and the evolution of guppy life histories. The evolution of these differences in life histories has been attributed to the higher mortality rates experienced by guppies in high-predation environments. Here, we evaluate whether there might be indirect effects of predation on the evolution of life-history patterns and whether there are environmental differences that are correlated with predation. To do so, we quantified features of the physical and chemical environment and the population biology of guppies from seven high-and low-predation localities. We found that high-predation …


Tiger Restoration In Asia: Ecological Theory Vs. Sociological Reality, Ronald Tilson, Philip J. Nyhus, Neil Franklin Jan 2001

Tiger Restoration In Asia: Ecological Theory Vs. Sociological Reality, Ronald Tilson, Philip J. Nyhus, Neil Franklin

Faculty Scholarship

No abstract provided.


Land Use Patterns In Relation To Lake Water Quality In The Lake George And Oaks Pond Watersheds, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2001

Land Use Patterns In Relation To Lake Water Quality In The Lake George And Oaks Pond Watersheds, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Other Area Studies

There has always been an inexplicable wonder associated with the beauty of Maine lakes. In addition to their aesthetic value, lakes and ponds provide important habitats for aquatic and terrestrial wildlife. The attraction of the lake's natural beauty, however, can increase recreational pressures that may lead to human induced eutrophication. Lake George and Oaks Pond were chosen as the Colby Environmental Assessment Team's (CEAT) study sites due to the concern about potential human induced eutrophication of both water bodies. Lake George and Oaks Pond are situated in southern Somerset County, Maine, and experience heavy recreational and developmental uses. Neither water …