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A Conceptual Framework For Clutch-Size Evolution In Songbirds, Thomas E. Martin

Wildlife Biology Faculty Publications

Causes of evolved differences in clutch size among songbird species remain debated. I propose a new conceptual framework that integrates aspects of traditional life-history theory while including novel elements to explain evolution of clutch size among songbirds. I review evidence that selection by nest predation on length of time that offspring develop in the nest creates a gradient in offspring characteristics at nest leaving (fledging), including flight mobility, spatial dispersion, and self-feeding rate. I postulate that this gradient has consequences for offspring mortality rates and parental energy expenditure per offspring. These consequences then determine how reproductive effort is partitioned among …

The Evolutionary Function Of Conscious Information Processing Is Revealed By Its Task-Dependency In The Olfactory System, Andreas Keller

Publications and Research

Although many responses to odorous stimuli are mediated without olfactory information being consciously processed, some olfactory behaviors require conscious information processing. I will here contrast situations in which olfactory information is processed consciously to situations in which it is processed non-consciously. This contrastive analysis reveals that conscious information processing is required when an organism is faced with tasks in which there are many behavioral options available. I therefore propose that it is the evolutionary function of conscious information processing to guide behaviors in situations in which the organism has to choose between many possible responses.

Invasive Plant Erodes Local Song Diversity In A Migratory Passerine, Yvette K. Ortega, Aubree Benson, Erick Greene

Biological Sciences Faculty Publications

Exotic plant invasions threaten ecosystems globally, but we still know little about the specific consequences for animals. Invasive plants can alter the quality of breeding habitat for songbirds, thereby impacting important demographic traits such as dispersal, philopatry, and age structure. These demographic effects may in turn alter song-learning conditions to affect song structure and diversity. We studied Chipping Sparrows (Spizella passerina) breeding in six savannas that were either dominated by native vegetation or invaded by spotted knapweed (Centaurea stoebe), an exotic forb known to diminish food resources and reproductive success. Here, we report that the prevalence of older birds was …

Direct And Relational Representation During Transitive List Linking In Pinyon Jays (Gymnorhinus Cyanocephalus), Cynthia Wei, Alan Kamil, Alan B. Bond

Alan Bond Publications

The authors used the list-linking procedure (Treichler & Van Tilburg, 1996) to explore the processes by which animals assemble cognitive structures from fragmentary and often contradictory data. Pinyon jays (Gymnorhinus cyanocephalus) were trained to a high level of accuracy on two implicit transitive lists. They were then given linkage training on the single pair that linked the two lists into a composite, 10-item hierarchy. Following linkage training, the birds were tested on nonadjacent probe pairs drawn both from within (B-D and 2–4) and between (D-1, E-2, B-2, C-3) each original list. Linkage training resulted in a significant transitory disruption in …

Migration Plasticity As An Adaptation To Climate Change: The Spatial Distribution And Abundance Of A Subset Of Neotropical Migrant Landbirds Wintering In The Northeastern United States, Juliette Goulet

Dissertations, Theses, and Capstone Projects

There is a need for accurate predictions of the effects of climate change on wildlife populations. Bioclimatic relationships however are potentially complicated by various environmental factors operating at multiple spatial and temporal scales. Therefore, in order to test the hypothesis that climate constraints of winter bird distributions are modified by species-specific responses to weather and climate, I relied on Christmas Bird Count data (CBC). With nearly 100 years of data, the CBC is a valuable source of information on historic and recent changes in the status and distribution of birds during the early winter period in the United States and …

Testing Assumptions Of Coevolution In An Egg-Rejecting Brood Parasite Host: Uncovering Sensory, Cognitive, And Evolutionary Drivers Of Responses To Parasitism In American Robins (Turdus Migratorius), Rebecca Croston

Dissertations, Theses, and Capstone Projects

Hosts of brood parasitic birds face fitness costs associated with rearing unrelated offspring. In response, the recognition and rejection of parasitic eggs is a common host defense. Brown-headed cowbirds (Molothrus ater) challenge coevolutionary theory, because although they exploit over 200 host species, they lay non-mimetic eggs, and most hosts do not combat cowbird parasitism with egg rejection. American robins (Turdus migratorius) are one of a handful of cowbird hosts known to recognize and remove cowbird eggs from the nest. I addressed the mechanistic and evolutionary drivers of egg rejection in this host species, by disentangling the roles of spectral tuning …

Long-Term Warming And The Size And Phenology Of Long Island Sound Plankton, Edward Rice

Dissertations, Theses, and Capstone Projects

In coastal ecosystems with decades of eutrophication and other anthropogenic stressors, the impact of climate change on planktonic communities can be difficult to detect. A time-series of monthly surface water temperatures in the Central Basin of Long Island Sound (LIS) from the late 1940s until 2012 indicates a warming rate of 0.03°C per year, with recent summer temperatures increasing most consistently. During this warming trend, the proportion of chlorophyll produced by smaller phytoplankton and flagellates appears to be higher during warmer summer and fall months, enabling an increase in annual chlorophyll despite static nutrient levels. The phenology of phytoplankton and …

Tribute To Tinbergen: The Place Of Animal Behavior In Biology, Joan E. Strassmann

Biology Faculty Research

Tinbergen is famous for emphasizing behavioral fieldwork and experimentation under natural circumstances, for founding the field of ethology, for getting a Nobel Prize, and for mentoring Richard Dawkins. He is known for dividing behavior studies into physiology, development, natural selection, and evolutionary history. In the decades since Tinbergen was active, some of the best research in animal behavior fuses Tinbergen's questions, connecting genes to behavioral phenotypes, for example. Behavior is the most synthetic of the life sciences, because observing the actions of an organism can tell us what all those physical and physiological traits are for. Insights from behavior tell …

Changes To Snowpack Energy State From Spring Storm Events, Columbia River Headwaters, Montana, Zachary M. Seligman, Joel T. Harper, Marco P. Maneta

Geosciences Faculty Publications

The generation and release of meltwater during the spring snowmelt season can be delayed because of spring storm episodes with snow accumulation and/or sustained subfreezing temperatures. The delayed release of snowmelt often extends beyond the particular storm event because of changes to the internal state of energy in the snowpack that prevents transmission of meltwater. Following a storm, two energy deficits internal to the snowpack must be overcome before surface melt can drain and exit the snowpack: 1) cold content created by heat lost during the episode must be removed and 2) dry pore space must be filled with liquid …

Riverine Macrosystems Ecology: Sensitivity, Resistance, And Resilience Of Whole River Basins With Human Alterations, Kevin E. Mccluney, N Leroy Poff, Margaret A. Palmer, James H. Thorp, Geoffrey C. Poole, Bradley S. Williams, Michael R. Williams, Jill S. Baron

Biological Sciences Faculty Publications

Riverine macrosystems are described here as watershed-scale networks of connected and interacting riverine and upland habitat patches. Such systems are driven by variable responses of nutrients and organisms to a suite of global and regional factors (eg climate, human social systems) interacting with finer-scale variations in geology, topography, and human modifications. We hypothesize that spatial heterogeneity, connectivity, and asynchrony among these patches regulate ecological dynamics of whole networks, altering system sensitivity, resistance, and resilience. Long-distance connections between patches may be particularly important in riverine macrosystems, shaping fundamental system properties. Furthermore, the type, extent, intensity, and spatial configuration of human activities …

A New Perspective On Trait Differences Between Native And Invasive Exotic Plants, A. Joshua Leffler, Jeremy J. James, Thomas A. Monaco, Roger L. Sheley

Natural Resource Management Faculty Publications

Functional differences between native and exotic species potentially constitute one factor responsible for plant invasion. Differences in trait values between native and exotic invasive species, however, should not be considered fixed and may depend on the context of the comparison. Furthermore, the magnitude of difference between native and exotic species necessary to trigger invasion is unknown. We propose a criterion that differences in trait values between a native and exotic invasive species must be greater than differences between co-occurring natives for this difference to be ecologically meaningful and a contributing factor to plant invasion. We used a meta-analysis to quantify …

The Ecological Effects Of Cattle Grazing On Reptiles And Small Mammals In A San Joaquin Valley Grassland, Michael William Tom

Master's Theses

Livestock grazing is a common and extensive land use practice in the United States occurring in a wide range of habitat types. As such, livestock grazing has the potential to alter ecosystem structure, function and community composition. The primary component (Chapter 1) of this thesis examined the effects of cattle grazing in a San Joaquin Valley grassland on two target taxa: reptiles and small mammals. The study took place on the Chimineas Unit of the Carrizo Ecological Reserve, San Luis Obispo County, California during Fall 2009 and Spring 2010. These taxa were sampled on matched pairs of two grazed and …

How Important Is Land-Based Foraging To Polar Bears (Ursus Maritimus) During The Ice-Free Season In Western Hudson Bay? An Examination Of Dietary Shifts, Compositional Patterns, Behavioral Observations And Energetic Contributions, Linda J. Gormezano

Dissertations, Theses, and Capstone Projects

Trophic mismatches between predators and their prey are increasing as climate change causes decoupling of phenological relationships. Predators linked to the life histories of a particular prey will have a more difficult time persisting through environmental change unless they can alter their behavior to maintain the historical match or possess the ability to pursue alternate prey. Arctic predators typically possess flexible foraging strategies to survive in the labile environment, however, quantifying the limits of those strategies can be difficult when life history information is incomplete. In such cases, piecing together different aspects of a predator's foraging behavior, particularly when environmental …

Historical Vegetation Of The Tiller Area, Douglas County, Oregon Based On Glo Survey Notes, O. Eugene Hickman, John Christy

Institute for Natural Resources Publications

This project was conducted in the Tiller area east of Canyonville, to develop a landscape perspective of historical vegetation for the early settlement era. The project area covered about 128,214 acres, of which 42% was private land, 17% BLM, and 41% USFS. This area of complex topography, transitional between interior valleys of the Umpqua River and the Cascade Range, has a small rural population base sometimes impacted by local natural resource problems and management. The study area includes portions of the South Douglas County Wildland-Urban Interface zone.

Historical land survey notes from General Land Office (GLO) were used to create …

Primate Energy Eexpenditure And Life History, Herman Pontzer, David A. Raichlen, Adam D. Gordon, Kara K. Schroepfer-Walker, Brian Hare, Matthew C. O’Neill, Kathleen M. Muldoon

Dartmouth Scholarship

Humans and other primates are distinct among placental mammals in having exceptionally slow rates of growth, reproduction, and aging. Primates’ slow life history schedules are generally thought to reflect an evolved strategy of allocating energy away from growth and reproduction and toward somatic investment, particularly to the development and maintenance of large brains. Here we examine an alternative explanation: that primates’ slow life histories reflect low total energy expenditure (TEE) (kilocalories per day) relative to other placental mammals. We compared doubly labeled water measurements of TEE among 17 primate species with similar measures for other placental mammals. We found that …

The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts

Ecology Collection

The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation …

Near Isometric Biomass Partitioning In Forest Ecosystems Of China, Dafeng Hui, Jun Wang, Weijun Shen, Xuan Le, Philip Ganter, Hai Ren

Biology Faculty Research

Based on the isometric hypothesis, belowground plant biomass (MB) should scale isometrically with aboveground biomass (MA) and the scaling exponent should not vary with environmental factors. We tested this hypothesis using a large forest biomass database collected in China. Allometric scaling functions relating MB and MA were developed for the entire database and for different groups based on tree age, diameter at breast height, height, latitude, longitude or elevation. To investigate whether the scaling exponent is independent of these biotic and abiotic factors, we analyzed the relationship between the scaling exponent and these factors. Overall MB was significantly related to …

Mutation Of A Dna Repair Enzyme Causes Lupus In Mice, Ali Senejani, Yanfeng Liu, Dawit Kidane, Stephen E. Maher, Caroline J. Zeiss, Hong-Jae Park, Michael Kashgarian, Jennifer Madison Mcniff, Daniel Zelterman, Alfred L.M. Bothwell, Joann B. Sweasy

Biology and Environmental Science Faculty Publications

A replication study of a previous genome-wide association study (GWAS) suggested that a SNP linked to the POLβ gene is associated with systemic lupus erythematosus (SLE). This SNP is correlated with decreased expression of Pol β, a key enzyme in the base excision repair (BER) pathway. To determine whether decreased Pol β activity results in SLE, we constructed a mouse model of POLβ that encodes an enzyme with slow DNA polymerase activity. We show that mice expressing this hypomorphic POLβ allele develop an autoimmune pathology that strongly resembles SLE. Of note, the mutant mice have shorter immunoglobulin heavy-chain junctions and …

Developmental Link Between Sex And Nutrition; Doublesex Regulates Sex-Specific Mandible Growth Via Juvenile Hormone Signaling In Stag Beetles, Hiroki Gotoh, Hitoshi Miyakawa, Asano Ishikawa, Yuki Ishikawa, Yasuhiro Sugime, Douglas J. Emlen, Laura C. Lavine, Toru Miura

Biological Sciences Faculty Publications

Sexual dimorphisms in trait expression are widespread among animals and are especially pronounced in ornaments and weapons of sexual selection, which can attain exaggerated sizes. Expression of exaggerated traits is usually male-specific and nutrition sensitive. Consequently, the developmental mechanisms generating sexually dimorphic growth and nutritiondependent phenotypic plasticity are each likely to regulate the expression of extreme structures. Yet we know little about how either of these mechanisms work, much less how they might interact with each other. We investigated the developmental mechanisms of sex-specific mandible growth in the stag beetle Cyclommatus metallifer, focusing on doublesex gene function and its …

Religion, Partisanship, And Attitudes Toward Science Policy, Ted G. Jelen, Linda A. Lockett

Political Science Faculty Research

We examine issues involving science which have been contested in recent public debate. These “contested science” issues include human evolution, stem-cell research, and climate change. We find that few respondents evince consistently skeptical attitudes toward science issues, and that religious variables are generally strong predictors of attitudes toward individual issues. Furthermore, and contrary to analyses of elite discourse, partisan identification is not generally predictive of attitudes toward contested scientific issues.

Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Climate change threatens to exacerbate the impacts of invasive species. In temperate ecosystems, direct effects of warming may be compounded by dramatic reductions in winter snow cover. Cheatgrass (Bromus tectorum) is arguably the most destructive biological invader in basins of the North American Intermountain West, and warming could increase its performance through direct effects on demographic rates or through indirect effects mediated by loss of snow. We conducted a two-year experimental manipulation of temperature and snow pack to test whether 1) warming increases cheatgrass population growth rate and 2) reduced snow cover contributes to cheatgrass’ positive response to …

A Unique Covalent Bond In Basement Membrane Is A Primordial Innovation For Tissue Evolution, Aaron L. Fidler, Roberto M. Vanacore, Sergei V. Chetyrkin, Vadim K. Pedchenko, Gautam Bhave, Viravuth P. Yin, Cody L. Stothers, Kristie Lindsey Rose, W. Hayes Mcdonald, Travis A. Clark, Dorin-Bogdan Borza, Robert E. Steele, Michael T. Ivy, The Aspirnauts, Julie K. Hudson, Billy G. Hudson

Biology Faculty Research

We recently discovered that the collagen IV scaffolds of bovine, mouse, and Drosophila melanogaster tissues are stabilized by sulfilimine chemical bonds (S = N) (20⇓–22). The bond is a covalent cross-link between methionine-93 (Met93) and lysine-211 or hydroxylysine-211 (Lys211/Hyl211) residues that stabilizes the noncollagenous (NC1) interface of adjoining triple helical protomers (Fig. 1A). Peroxidasin, an animal heme peroxidase embedded in basement membrane, forms these sulfilimine cross-links by producing hypohalous acids as intermediates for Met93 oxidization (21, 22). Here, we explored whether the sulfilimine cross-link of collagen IV is a fundamental requirement in the genesis and evolution of tissues in Eumetazoa. …

2matrix: A Utility For Indel Coding And Phylogenetic Matrix Concatenation, Nelson R. Salinas, Damon P. Little

Publications and Research

Premise of the study: Phylogenetic analysis of DNA and amino acid sequences requires the creation of files formatted specifically for each analysis package. Programs currently available cannot simultaneously code inferred insertion/deletion (indel) events in sequence alignments and concatenate data sets.

Methods and Results: A novel Perl script, 2matrix, was created to concatenate matrices of non-molecular characters and/or aligned sequences and to code indels. 2matrix outputs a variety of formats compatible with popular phylogenetic programs.

Conclusions: 2matrix efficiently codes indels and concatenates matrices of sequences and non-molecular data. It is available for free download under a GPL (General Public License) open …

The Longhorn Beetles (Coleoptera: Cerambycidae) Of Nebraska, Usa: New State Records, A Checklist Of Known Species, And Distribution Maps, Stephen M. Spomer

University of Nebraska State Museum: Entomology Papers

One hundred eighty-three species/subspecies of longhorn beetles are recorded from Nebraska, an increase of 19 species since 1971. The greatest number of recent discoveries have come from sites along the Missouri River, especially Indian Cave State Park in southeastern Nebraska, as well as the Pine Ridge at Chadron, Nebraska.

Using Indicators Of Biotic Integrity For Assessment Of Stream Condition, Stephanie A. Ogren

Dissertations, Master's Theses and Master's Reports - Open

Multiple indices of biotic integrity and biological condition gradient models have been developed and validated to assess ecological integrity in the Laurentian Great Lakes Region. With multiple groups such as Tribal, Federal, and State agencies as well as scientists and local watershed management or river-focused volunteer groups collecting data for bioassessment it is important that we determine the comparability of data and the effectiveness of indices applied to these data for assessment of natural systems. We evaluated the applicability of macroinvertebrate and fish community indices for assessing site integrity. Site quality (i.e., habitat condition) could be classified differently depending on …

Variation In Setal Micromechanics And Performance Of Two Gecko Species, Travis J. Hagey, Jonathan B. Puthoff, Madisen Holbrook, Luke J. Harmon, Kellar Autumn

Biology

Biomechanical models of the gecko adhesive system typically focus on setal mechanics from a single gecko species, Gekko gecko. In this study, we compared the predictions from three mathematical models to experimental observations considering an additional gecko species Phelsuma grandis, to quantify interspecific variation in setal micromechanics. We also considered the accuracy of our three focal models: the frictional adhesion model, work of detachment model, and the effective modulus model. Lastly, we report a novel approach to quantity the angle of toe detachment using the Weibull distribution. Our results suggested the coupling of frictional and adhesive forces in isolated setal …

Patch Burn‐Grazing: An Annotated Bibliography, Rajeeva Voleti, Stephen L. Winter, Sherry Leis

School of Natural Resources: Faculty Publications

Patch burn‐grazing is a rangeland management strategy that exploits the attraction of grazing animals to recently burned areas in order to achieve management objectives. When fire is applied to a landscape in a patchy manner, leaving some patches unburned, the resulting grazing animal activity, forage utilization, and animal impact are patchily distributed within that landscape as well. Areas that have been recently burned tend to be characterized by the highest levels of grazing animal activity while areas that have gone the longest without burning tend to be characterized by the lowest levels of grazing animal activity. This can be advantageous …

Proceedings Of The Twelfth North American Crane Workshop, David A. Aborn, Richard Urbanek

Proceedings of the North American Crane Workshop

CONTENTS

PREFACE iii

RESEARCH PAPERS

DISTRIBUTION, ABUNDANCE, AND MIGRATION TIMING OF GREATER AND LESSER SANDHILL CRANES WINTERING IN THE SACRAMENTO-SAN JOAQUIN RIVER DELTA REGION OF CALIFORNIA - . Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, and Joseph P. Fleskes 1

CHARACTERISTICS OF SANDHILL CRANE ROOSTS IN THE SACRAMENTO-SAN JOAQUIN DELTA OF CALIFORNIA - . Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, and Joseph P. Fleskes 12

EFFECTS OF WIND FARMS ON SANDHILL CRANE PLAYA OCCUPANCY ON THE TEXAS HIGH PLAINS - Laura Navarrete and Kerry L. Griffis-Kyle 20

EVALUATION OF …

An Illustrated Id Guide To The Crayfishes Found In Nebraska Native And Non-Native, Steve Schainost

Nebraska Invasive Species Program

There are five crayfishes native to Nebraska. These are:

Orconectes immunis (papershell crayfish)

Orconectes virilis (northern crayfish)

Orconectes neglectus neglectus (ringed crayfish)

Cambarus diogenes (Devil crayfish)

Procambarus gracilis (prairie crayfish)

Three additional non-native crayfishes have also been found here:

Orconectes rusticus (rusty crayfish) [bait tanks and established in two ponds in Omaha]

Procambarus clarkii (red swamp crayfish) [bait tanks]

Procambarus acutus (White River crayfish) [bait tanks]

I will attempt here to provide a photographic guide to field identification, one species per page.

Evaluating Trends In Valve Shape In Eunotia By Comparing Fossil And Modern Species, Jordan Bishop-Genovesi

Environmental Studies Honors Papers

No abstract provided.