Biology Commons^™

From Growth To Extinction: Explored By Life History And Metabolic Theory, Wenyun Zuo

Biology ETDs

The laws of energy and material conservation are fundamental principles across various scales and systems. Based on the conservation laws, I derive several theoretical models to understand mechanisms behind the energy budget of ontogenetic growth and the pattern of the late Pleistocene extinction of megafauna in the Americas. First, I present a model, empirically grounded in data from birds and mammals, that correctly predicts how growing animals allocate food energy between synthesis of new biomass and maintenance of existing biomass. Previous energy budget models have typically been based on rates of either food consumption or metabolic energy expenditure. The model …

Stable Isotopes Provide Insight Into The Use Of Wildlife Water Developments By Resident And Migrant Birds In The Sonoran Desert Of Arizona, Theresa C. Hyde

Biology ETDs

Several studies have looked at the importance of man-made water resources to wildlife in desert regions. To our knowledge, however, none have attempted to directly quantify their importance to both resident and Neotropical migratory birds. During the spring and summer from 2007-2009, we enriched man-made water developments in the Sonoran Desert on the Kofa National Wildlife Refuge, Arizona. We enriched water developments using deuteriated water and sampled the body water pools of resident and migrant birds to quantify development use. We used a simple two end-point mixing model to estimate the proportion of an individual birds body water pool that …

Divergence In The Ecology Of Two Species Of Gambusia In Secondary Contact, Daniella Marilyn Swenton

Biology ETDs

Gambusia nobilis, a federally endangered species, and G. affinis (Poeciliidae) are small, livebearing fishes found in the southwestern U.S. The invasive G. affinis has been introduced globally to control mosquito populations. It is found in some populations of G. nobilis on Bitter Lake National Wildlife Refuge (BLNWR), the field site for this study. It is unclear to what extent the two species have diverged in behavior and ecology and how extensively they have hybridized on BLNWR, thereby threatening the endangered G. nobilis via genetic introgression. In this study I examined divergence in behavior and ecology between two species with four …

Growth, Mortality, And Life-History Scaling Across Species, Eric L. Charnov, Wenyun Zuo

Biology Faculty & Staff Publications

No abstract provided.

Average Adult Size In Female Lizards, Eric Charnov, Robin Warne

Biology Faculty & Staff Publications

No abstract provided.

Body Size Is The History Of Life: Growth Confronting Landscapes Of Death, Eric Charnov

Biology Faculty & Staff Publications

No abstract provided.

Human Hunting Mortality Threshold Rules For Extinction In Mammals (And Fish), Eric Charnov, Wenyun Zuo

Biology Faculty & Staff Publications

No abstract provided.

Nf-Κb Translocation In Response To Different Lps Chemotypes In Murine Macrophages, Elizabeth L. Carles

Biology ETDs

Nuclear Factor κB (NF-κB) proteins make up a large family of eukaryotic transcription factors that regulate many important cellular functions, including cell signaling, cell growth, development, cell death by apoptosis, and immune and inflammatory responses, and has been shown to be involved in multiple human diseases. NF-κB proteins are subject to careful regulation in the cell, and are regulated at multiple levels. A family of inhibitory proteins exist (called IκB proteins) which bind to NF-κB and cause it to be localized in the cytoplasm. There are multiple signal transduction pathways that can lead to the activation of NF-κB. These signal …

The Spatial Ecology Of Galapagos Tortoises And New Mexico's Reptiles, Jacek Tomasz Giermakowski

Biology ETDs

The analysis of spatial processes and spatial heterogeneity is an important part of ecology because distribution of organisms in space partly defines ecology as a discipline. In addition, advances in analysis of DNA, geographical computing and the availability of vast amounts of environmental data obtained by satellites provide new opportunities for studying ecology at different spatial and phylogenetic scales. My research takes advantage of information gathered by satellites and adds modeling and data collected on the distribution of different reptiles to examine processes at various spatial and temporal scales. In Chapter 1 I describe how juvenile Galapagos tortoises change their …

The Isotopic Composition Of Light-Enhanced Dark Respiration (Ledr) In C3 And C4 Plants, Susan Christy Mirabal

Biology ETDs

Light-enhanced dark respiration (LEDR) has been studied in C3 plants as a method to elucidate the careful balance between photosynthesis and respiration yet little is known about the metabolic properties by which it occurs in C4 plants. Using a tunable diode laser gas exchange system, we analyzed transient isotopic shifts in leaf-respired CO2 associated with LEDR at 10Hz frequency from Populus deltoides (C3), Amaranthus hypochondriacus (C4 NAD-ME), and Zea mays (C4 NADP-ME). The results suggest that:

(1) Post-photosynthetic fractionations are different between C3 and C4 (and within C4) plants, where A. hypochondriacus exhibited an unexpected LEDR response (Fig. 3, Table …

Biogeography Of Alien Vertebrates In The Galapagos Islands: Patterns, Processes, And Conservation Implications, Reese Brand Phillips

Biology ETDs

Alien species are one of the principal threats to global biodiversity. Insular ecosystems have proven exceptionally susceptible to invasion by aliens and vulnerable to their negative effects. Some of the most destructive alien species are vertebrates, in part due to their having been introduced to islands worldwide. Rodents (Rattus spp. and Mus musculus) are among the most widespread and devastating invasive species for insular flora and fauna. In this research I investigate the biogeographic patterns and processes of alien vertebrates in the Galapagos Islands, focusing on the mechanisms that influence their dispersal and colonization within the archipelago. In the first …

Nutrient Cycling In Impacted Stream Ecosystems: From Microbes To Watersheds, David James Van Horn

Biology ETDs

The conditions found in stream ecosystems are an integration of watershed characteristics and processes. Anthropogenic disturbances are part of this integration and include direct inputs to streams, alteration of riparian areas, and modification of catchment properties which affect material inputs. Impacts to discrete portions of terrestrial watersheds combine as water moves down gradient, transporting the byproducts of catchment disturbances to streams including, nutrients, organic materials, particulates, and toxins. This dissertation explores the effects of disturbance on nutrient cycling in stream ecosystems at three spatial scales: the patch scale includes localized processes and assemblages, the reach scale encompasses tens to hundreds …

Always Read The Introduction: Integrating Regulatory And Coding Sequence Evolution In Yeast, Annette M. Evangelisti

Biology ETDs

We analyze duplicate genes in a yeast, Saccharomyces cerevisiae with the aim of determining a genes history and to observe that gene in its genomic context. In Chapter 2 we show that the fate of a duplicate gene pair is in part determined by its genome location. Moreover, we show that for two classes of duplicate genes, resulting from either small-scale duplication or whole-genome duplication, this fate can often be assessed by measuring the patterns of asymmetry in the sequence divergence of the genes in question. In Chapter 3 we study duplicate genes in the context of their local environments …

High-Throughput Genomic/Proteomic Studies: Finding Structure And Meaning By Similarity, George Sidney Davidson

Biology ETDs

The post-genomic challenge was to develop high-throughput technologies for measuring genome scale mRNA expression levels. Analyses of these data rely on computers in an unprecedented way to make the results accessible to researchers. My research in this area enabled the first compendium of microarray experiments for a multi-cellular eukaryote, Caenorhabditis elegans. Prior to this research approximately 6% of the C. elegans genome had been studied, and little was known about global expression patterns in this organism. Here I cluster data from 553 different microarray experiments and show that the results are stable, statistically significant and highly enriched for specific biological …

Female Perception Of Testeronized Male Facial Images: Evidence Of A Co-Evolutionary Tradeoff Responsive To Conditions For Both Competition And Cooperation, Melissa L. Franklin

Biology ETDs

Theorists and researchers who examine the evolutionary ecology of mating dynamics consider two primary forces, intrasexual and intersexual, as important pressures of selection. Bilateral symmetry and, more controversially, hormone markers in many species, impart information that has been found to influence some aspects of intersexual selection. Both symmetry, as a sign of developmental stability, and hormone markers (i.e., testosteronized traits as cues of immunocompetence) have been classically treated as signals of genetic fitness (Moller & Swaddle, 1997; Hamilton & Zuk, 1982), although neither are consistently shown to correlate with increased mating success. Indeed, results between studies on either trait independently …

Genome Architecture In The Fungal Kingdom, Diego Antonio Martinez

Biology ETDs

Previous studies have suggested that the location of genes in genomes is not random; instead they may be organized in a way that is beneficial to cellular processes and the organism. While a few studies have investigated the organization of genes on a whole genome scale, they were limited in the functions of genes used in the search and in the number and type of genomes searched. With the recent explosion of available fungal genomes and tools to automatically annotate many genes in a short period of time, it is now possible to obtain a global view of the level …

Temporal Dynamics And Spatial Analysis Of Competing Dengue 2 Virus Strains In The Americas, Stacy O'Neil Scholle

Biology ETDs

The dengue virus is the causative agent of an important re-emerging infectious disease that has become increasingly significant in tropical America and the Caribbean due to the infiltration of a more pathogenic Asian/American strain of dengue serotype 2 into the population. This invading strain is responsible for epidemics of dengue hemorrhagic fever, a life-threatening disease that was not previously a large public health concern in the region. Here, I create a historical map of the invasion and replacement of the endemic American strain of dengue 2 by the Asian/American strain, showing that the timing of invasion spans 25 years, and …

Comparison Of Microbial Communities On Roots, Ceilings And Floors Of Two Lava Tube Caves In New Mexico, Jessica R. Snider

Biology ETDs

Lava tube caves possess a rich and patchy mosaic of nutrients and water that fosters a wide variety of microbial life. Water percolating past vegetation and through surface soils introduces dissolved carbon and nitrogen into caves. Roots provide even higher levels of carbon, nitrogen and microorganisms as they grow into the cave environment from surface vegetation. I hypothesized that this mosaic of nutrients and energy resources has a direct effect on the distribution and composition of microbial communities within caves. To test this hypothesis, I selected two lava tube caves in New Mexico, USA and identified six zones consisting of …

Habitat Variables, Mammal Interactions, And Recovery Approaches Important To A Rare, New Mexican Butterfly, Euphydryas Anicia Cloudcrofti (Lepidoptera: Nymphalidae), Julie Lincoln Mcintyre

Biology ETDs

This research investigated three study topics pertaining to the habitat and ecology of the Sacramento Mountains checkerspot butterfly (Euphydryas anicia cloudcrofti) with the goal of contributing to effective conservation for this rare species. In the first study, abiotic and biotic habitat variables were found to be different between occupied and unoccupied habitat. Connectivity, host plant resource concentration, and plant structural diversity corresponded with butterfly presence at the scales of landscape, meadow, host plant patch, and natal host plant. High habitat quality, low isolation, broad host plant patch area, and high host plant patch density were associated with occupied habitats. Adults …

Tracing Deuterium Through The Food Web And Into Birds And Mammals Along An Elevational Gradient In The Southern Rocky Mountains, Matthew J. Baumann

Biology ETDs

Animals incorporate local δ2H values from available water and dietary sources during tissue synthesis, which can provide evidence of elevational movements if multiple tissues with different turnover times are examined. Here we test the applicability of using δ2H as an indicator of altitudinal movements by examining multiple tissues (δ2Hbw (body water), δ2Hfeather, δ2Hfur, and δ2Hclaw) in birds and mammals in the Sangre de Cristo Mountains. Additionally, we measured δ2Hsw (stem water) and insect δ2bw and δ2wb (whole body) values to assess changes with elevation. We sampled 15 species of birds and two small mammal species along with potential food sources …

Dispersal, Facilitation, And Burrow Architecture In Banner-Tailed Kangaroo Rats, Andrew J. Edelman

Biology ETDs

The largest and most dominant kangaroo rat species in the Chihuahuan Desert is the banner-tailed kangaroo rat (Dipodomys spectabilis). This keystone species constructs mounds containing a complex burrow system around which their ecosystem engineering activities are centered. I studied a population of banner-tailed kangaroo rats at the Sevilleta National Wildlife Refuge, New Mexico from 2005-2009. Specifically, I examined how banner-tailed kangaroo rats: 1) modify their mounds in response to seasonal conditions; 2) spatially affect harvester ants (Pogonomyrmex rugosus) through ecosystem engineering activities; and 3) differ in timing of natal dispersal between sexes. I used mark-recapture, genetic, experimental, and spatially-explicit methods …

Respiratory Physiology During Gravidity In Crotaphytus Collaris And Gambelia Wislizenii, Casey Anderson Gilman

Biology ETDs

During gravidity lizards experience a significant decrease in lung volume as a result of compression by growing eggs within the body cavity. In order to understand the effect of this decrease in lung volume on respiratory physiology of gravid egg-laying lizards I measured changes in: total lung volume, resting and post-exercise expired volume, minute volume, respiratory frequency, and carbon dioxide production during reproduction in Crotaphytus collaris and Gambelia wislizenii. I found that compression of the lungs by eggs resulted in an average 48% (range: 26 to 70%) decrease in total lung volume in C. collaris, and an average 38% (range: …

Molecular Phylogenetic Investigation Of Microbial Diversity And Nitrogen Cycling In Lava Tubes, Jennifer Jane Marshall Hathaway

Biology ETDs

Worldwide, lava tubes host colorful microbial mats on their walls and ceilings. Little is known about the diversity and ecological roles of the bacteria communities in the subsurface ecosystem of lava tubes. White and yellow microbial mats were collected from four lava tubes from the Azorean island of Terceira and from four lava tubes on the Big Island of Hawaii, to compare and contrast the diversity of bacteria found in lava tubes. The 16S rRNA gene was sequenced in order to determine the diversity within these caves, and to begin to elucidate the environmental controls on microbial diversity in the …

The Role Of Spatial And Genetic Modeling To Biogeography, Dolly Lyne Crawford

Biology ETDs

One of the most persistent challenges in biology is explaining the distribution of animal taxa. Quantitative explanations for the distribution of organisms are challenged by the complexity of factors that potentially limit a species range, including topography, ecology, climate and biology. Because of limits on data and approaches, early biogeographers were hampered in their ability to explain patterns. Here, I benefit from two primary developments in biogeography. My research draws from the accumulation of data across several scientific disciplines and advances in spatial and statistical approaches to examine the distribution of animal taxa within an integrative biogeography framework. I combine …

The Physiological Ecology And Evolution Of Freezing Tolerance In Diploid Larrea Sp., Juliana Sibylla Medeiros

Biology ETDs

A basic understanding of vegetation responses to temperature and precipitation variability is paramount to the understanding of ecological adaptation, and comparisons across warm deserts are needed to increase our understanding of the controls on establishment in warm desert ecosystems. At the high latitude edges of warm deserts drought and freezing lower plant performance due to xylem dysfunction, as freeze-thaw embolism reduces stomatal conductance, or damage to leaf photosynthetic apparatus, as tissue desiccation reduces photosynthetic efficiency. Variation in these physiological responses can be observed across life-history stages, genetic background, climate gradients, and species, and this variation may be acted on by …

The Effect Of Plant Source Location On Restoration Success: A Reciprocal Transplant Experiment With Winterfat (Krascheninnikovia Lanata), Melanie G. Barnes

Biology ETDs

It is increasingly important that plant propagules used in revegetation projects are from a location that is geographically or ecologically similar to the planting site. To better understand the consequences of using non-local plant materials, I chose to study the population biology of the widespread shrub winterfat (Krascheninnikovia lanata, Chenopodiaceae) among five populations in New Mexico, USA. Winterfat plant morphology among the five populations was compared, and the rate of emergence and floral onset was measured in a greenhouse common garden. A reciprocal transplant experiment was planted in which individuals from different locations were planted in replicate common gardens. Transplant …

Statistical Methods In Microarrays And High-Throughput Flow Cytometry, Osorio Meirelles

Biology ETDs

Abstract-I

Background: Heterogeneous cell populations have previously been described as noisy. However, recent studies have demonstrated that heterogeneity can be biologically significant. We present here an approach for rapid and complete identification of heterogeneous cell populations from high-throughput flow cytometry data. We have developed a novel measure Slope Differentiation Identification (SDI) using flow cytometry-based protein expression, quantifying the rate of change in protein expression between two conditions (exponential and stationary phase) of yeast cells, as a function of cell size or cell granularity.

Results: SDI had superior Gene Ontology enrichment when compared with other approaches such as k-means clustering and …

Environmental Regulation Of Carbon Isotope Discrimination And Internal Co2 Conductance In C3 Leaves, Christopher Paul Bickford

Biology ETDs

Stable carbon isotopes are powerful tools for elucidating leaf- and ecosystem- level processes, and recent technological developments provide new opportunities to assess the isotopic flux during leaf gas exchange. In these studies I used a tunable diode laser spectroscope coupled to a infra-red gas analyzer to measure the isotopic composition of leaf gas exchange at high frequency in both field and greenhouse settings and assess environmental regulation of carbon isotope discrimination (Δ) and internal conductance of CO2 to sites of carboxylation (gi). I measured Δ and gi across diurnal and seasonal periods in field-grown Juniperus monosperma trees and used these …

Description Of Thermonectus Nigrofasciatus And Rhantus Binotatus (Coleoptera:-Dytiscidae) Mating Behavior, Lauren M. Cleavall

Biology ETDs

Models of sexual conflict predict that diving beetles should respond morphologically and behaviorally during mating events to overcome the opposing sex. Morphological and behavioral adaptations may result from pressures by one sex to overcome resistance to mating attempts of the opposite sex. Morphological data supports an evolutionary arms race in diving beetles (Dytiscidae) exhibited in a series of adaptations attributable to sexual conflict between males and females. Males of certain Dytiscinae have sucker shaped adhesion setae on their front and mid tarsi to improve attachment to the females elytra prior to and during mating, whereas females have evolved grooves, ridges, …

Transient De-Coupling Of Photosynthesis And Stomatal Conductance In Response To Leaf Primary Vein Cut In Helianthus Annuus, Laura Elizabeth Green

Biology ETDs

Control of stomatal aperture is the primary way plants regulate gas exchange in the short-term, but what triggers stomatal responses to water stress is still debated. Chlorophyll-a fluorescence imaging, local leaf temperature, and gas exchange were measured simultaneously following a cut to primary leaf vein of Helianthus annuus to access the effect of local leaf xylem cavitation on leaf function. The treatment was repeated under 3 different vapor pressure deficit (VPD) conditions. Surprisingly, photosynthesis (A) and stomatal conductance (gs) responded inversely immediately following the treatment, indicating that A was not CO2 limited by stomatal closure. Comparisons of fluorescence images and …