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A Dimensionless Invariant For Relative Size At Sex Change In Animals: Explanation And Implications, Andy Gardner, David Allsop, Eric Charnov, Stuart West

Biology Faculty & Staff Publications

Recent comparative studies across sex-changing animals have found that the relative size and age at sex change are strikingly invariant. In particular, 91%-97% of the variation in size at sex change across species can be explained by the simple rule that individuals change sex when they reach 72% of their maximum body size. However, this degree of invariance is surprising and has proved controversial. In particular, it is not clear why this result should hold, given that there is considerable biological variation across species in factors that can influence the evolutionarily stable timing of sex change. Our overall aim here …

Cardiac Protein Rgs2: Structural And Functional Determinants, Stephanie Jan Chambers

Undergraduate Honors Capstone Projects

In this study, I explored the structure-function relationships of a cardiac RGS (regulator of G-protein signaling) protein, RGS2.

Contractions of the heart are triggered by calcium ions (Ca) entering heart cells through L-type Ca channels (1a). The activity of L-type channels (and thereby Ca influx) is modulated by cell surface receptors that couple to intracellular G proteins. G proteins in turn, are regulated by a newly-discovered family of proteins called RGS. RGS proteins speed the hydrolysis of GTP by G proteins, and thereby control the strength and duration of G protein-mediated signals. Stimulation of G proteins, which are coupled to …

Diaspora, A Large Family Of Ty3-Gypsy Retrotransposons In Glycine Max, Is An Envelope-Less Member Of An Endogenous Plant Retrovirus Lineage, Sho T. Yano, Bahman Panbehi, Arpita Das, Howard M. Laten

Biology: Faculty Publications and Other Works

Background

The chromosomes of higher plants are littered with retrotransposons that, in many cases, constitute as much as 80% of plant genomes. Long terminal repeat retrotransposons have been especially successful colonizers of the chromosomes of higher plants and examinations of their function, evolution, and dispersal are essential to understanding the evolution of eukaryotic genomes. In soybean, several families of retrotransposons have been identified, including at least two that, by virtue of the presence of an envelope-like gene, may constitute endogenous retroviruses. However, most elements are highly degenerate and are often sequestered in regions of the genome that sequencing projects initially …

Digestibility, Nitrogen Balance, And Blood Metabolites In Llama And Alpaca Fed Barley And Barley Alfalfa Forages., Heather Loree Davies

Theses and Dissertations

These projects were conducted to determine the digestibility of forage diets with differing CP levels in llamas and alpacas. The Utah study was designed to compare llama and alpaca nutritional parameters to determine if nutritional recommendations for llamas can be directly extrapolated to alpacas. The first study evaluated the effects of forage quality on blood metabolites and nitrogen balance in mature, intact male llamas (n = 4, 36 ± 4.4 months, 87 ± 17 kg) at high altitude in Letanias, Bolivia (4,267 m = aprox.14,000 ft above sea level). A second experiment was conducted with eight adult gelded camelids (n …

Are Nutrients Assimilated By Juveniles Of The Brittle Star Amphipholis Squamata (Echinodermata: Ophiuroidea)?, Elizabeth A.G. Whitehill '05

Honors Projects

Over 50 species of brittle stars (Echinodennata: Ophiuroidea) are known to brood their developmental stages (embryos and larvae) through metamorphosis in internal structures called bursae (Hyman, 1955). In some of these brooding ophiuroids, the source of the organic material necessary to support the growth and development of the embryos is somewhat obscure because the amount of material required is not maternally supplied in the egg. A species that follows this example is Amphipholis squamata (Delle Chiaje). Previous studies (Fontaine and Chia 1968) have shown that the larvae of A. squamata are able to acquire the organic material needed to sustain …

The Biology Of Canadian Weeds. 131. Polygonum Aviculare L., Mihai Costea, François J. Tardif

Biology Faculty Publications

A review and assessment of biological information as well as personal data are provided for Polygonum aviculare in Canada. The species has been revised taxonomically and the six subspecies that occur in Canada are presented. Three of the subspecies, P. aviculare subsp. aviculare, P. aviculare subsp. neglectum and P. aviculare subsp. depressum are weeds introduced to Canada from Europe. A fourth subspecies, P. aviculare subsp. buxiforme is apparently native to North America. The geographical distribution of the latter four subspecies is very wide. Plants exhibit a high phenotypic plasticity and genetic variability, and they easily adapt to a multitude …

Hunters Ring Dinner Bell For Ravens: Experimental Evidence Of A Unique Foraging Strategy, Crow White

Biological Sciences

We have long known that corvids are adaptively flexible in behavior, but have rarely tested their flexibility and creativity in solving problems outside the laboratory. Through a carefully controlled experiment conducted in the wild, I have found that Common Ravens (Corvus corax) fly toward gunshot sounds, presumably in order to locate animal gut piles left by hunters. This is the first conclusive evidence of any scavenger species pursuing gunshots. Furthermore, ravens exhibited this behavior only when gunshots were fired from within forested habitat, when the shots may be most valuable to them for locating gut piles. Interestingly, raven behaviors suggest …

Bufadienolides In The Chemical Defenses Of The Toads, Bufo Americanus And Bufo Fowleri, Catherine E. Merovich

Dissertations

I investigated the steroidal chemical defenses (bufadienolides) of Bufo americanus and Bufo fowleri. By the nature of their complex, biphasic life cycles, toads, like other amphibians are important components of aquatic and terrestrial habitats and are prey to numerous invertebrates and vertebrates. Bufadienolides are presumed to be important anti-predatory compounds although much of their chemical ecology is poorly understood. I investigated (1) ontogenetic variation in bufadienolides, (2) bufadienolides from adult parotoid secretion, (3) effectiveness of bufadienolides against a terrestrial predator, and (4) effectiveness of bufadienolides against an aquatic predator. I hypothesized that B. americanuswould have a more extensive …

Changes In Glial Cell Line Derived Neurotrophic Factor And Nerve Growth Factor Expression With Development, Age, Exercise And Hypertension, Bertha C. Rebimbas-Cohen

Dissertations

Neurotrophic factors are important for neuronal growth, survival, and maintenance of cell phenotype. Glial cell line-derived neurotrophic factor (GDNF) affects sensory, autonomic and somatic motor neurons and nerve growth factor (NGF) affects sensory and sympathetic neurons. NGF and GDNF are produced by cardiac muscle and have potent effects on sensory and autonomic neuronal innervation of blood vessels. Neural innervation plays a key role in blood vessel function. Since neural innervation of blood vessels may be regulated by growth factors, we wanted to determine what changes would occur to NGF and GDNF levels with maturity, exercise and hypertension.

Changes in GDNF …

Function And Role Of Synaptotagmin Proteins In Yeast, Aaron J. Yang

Renée Crown University Honors Thesis Projects - All

In the genome of the budding yeast, Saccharomyces cerevisiae, a family of proteins is encoded that resembles the Ca2+ sensing synaptotagmins present in neuronal cells of higher eukaryotes. The synaptotagmins couple a rise in cytosolic Ca2+ with synaptic vesicle formation and release during the process of vesicular trafficking and exocytosis. This process is important in higher organisms for neurotransmitter release and signal transmission. At least a dozen synaptotagmin isoforms exist, some that are expressed outside the nervous system, suggesting that the synaptotagmin proteins might regulate membrane trafficking in a variety of different cell types. The synaptotagmin proteins in higher …

Increased Action Potential Firing Rates Of Layer 2/3 Pyramidal Cells In The Prefrontal Cortex Are Significantly Related To Cognitive Performance In Aged Monkeys, Yu Ming Chang, Douglas L. Rosene, Ronald J. Killiany, Lisa A. Mangiamele, Jennifer I. Luebke

Biological Sciences: Faculty Publications

The neurobiological substrates of significant age-related deficits in higher cognitive abilities mediated by the prefrontal cortex (PFC) are unknown. To address this issue, whole-cell current-clamp recordings were used to compare the intrinsic membrane and action potential (AP) firing properties of layer 2/3 pyramidal cells in PFC slices from young and aged behaviorally characterized rhesus monkeys. Most aged subjects demonstrated impaired performance in Delayed Non-Match to Sample (DNMS) task acquisition, DNMS 2 min delay and the Delayed Recognition Span task. Resting membrane potential and membrane time constant did not differ in aged relative to young cells, but input resistance was significantly …

The Glucose And Insulin Responsiveness Of The Rat Glucose-6-Phosphate Dehydrogenase Promoter, Daryl Arkwright-Keeler

Dissertations

The regulation of expression of some enzymes involved in glucose homeostasis and fat metabolism requires both insulin and glucose to elicit an effect, while the regulation of others requires only one. Glucose-6-phosphate dehydrogenase (G6PDH), an important enzyme involved in glucose homeostasis, has been shown to be transcriptionally regulated by carbohydrate feeding in rat liver, a diet regime that increases the levels of both glucose and insulin. Our lab had previously shown that insulin induces expression of G6PDH, thus we wanted to determine if glucose also induced G6PDH expression and if so, are the glucose and insulin responses mediated through identical …

Phylogenetic Relationship Of Forest Spiny Pocket Mice (Genus Heteromys) Inferred From Mitochondrial And Nuclear Markers With Implications For Species Boundaries, Malinda Wallentine Gonzalez

Theses and Dissertations

I constructed a best estimate phylogeny based on congruence of multiple data sources. In recent years molecular data has been used both to construct phylogenies of taxonomic groups and to aid in the delimitation of new species. I generated and analyzed sequence data for forest spiny pocket mice (Genus Heteromys) for the mitochondrial gene cyt b (1143 bp) and two nuclear gene segments MYH2 (252 bp) and EN2 (189 bp). I used maximum parsimony and Bayesian analyses to infer relationships among species and to provide a framework for using a species delimitation method to investigate the possibility of multiple …

A Multidisciplinary Comparison Of Rules-Driven Writing: Similarities In Legal Writing, Biology Research Articles, And Computer Programming, Karen L. Koch

Journal of Legal Education

No abstract provided.

Complete Genome Sequence Of The Probiotic Lactic Acid Bacterium Lactobacillus Acidophilus Ncfm, Eric Altermann, W. Michael Russell, M. Andrea Azcarate- Peril, Rodolphe Barrangou, B. Logan Buck, Olivia Mcauliffe, Nicole Souther, Alleson Dobson, Tri Duong, Michael Callanan, Sonja Lick, Alice Hamrick, Raul J. Cano, Todd R. Klaenhammer

Biological Sciences

Lactobacillus acidophilus NCFM is a probiotic bacterium that has been produced commercially since 1972. The complete genome is 1,993,564 nt and devoid of plasmids. The average GC content is 34.71% with 1,864 predicted ORFs, of which 72.5% were functionally classified. Nine phage-related integrases were predicted, but no complete prophages were found. However, three unique regions designated as potential autonomous units (PAUs) were identified. These units resemble a unique structure and bear characteristics of both plasmids and phages. Analysis of the three PAUs revealed the presence of two R/M systems and a prophage maintenance system killer protein. A spacers interspersed direct …

Vegetation Response Of A Wyoming Big Sagebrush (Artemisia Tridentata Ssp. Wyomingensis) Community To 6 Mechanical Treatments In Rich County, Utah, Daniel David Summers

Theses and Dissertations

In recent years, the importance of sagebrush to shrub-steppe ecosystems and associated plant and animal species has been recognized. The historical removal of herbaceous species by excessive and uncontrolled livestock grazing on many of our sagebrush ecosystems has resulted in a stagnant state where dense, competitive stands of sagebrush prevent herbaceous species from recovering. Most early research on sagebrush control was directed toward eradication to increase herbaceous forage for livestock production, rather than sagebrush thinning to improve shrub vigor and understory production for wildlife habitat and community diversity. Mechanical treatments have the ability to retain shrub and herbaceous components, while …

The Relationship Between Pelagic Larval Duration And Range Size In Tropical Reef Fishes: A Synthetic Analysis, Sarah E. Lester, Benjamin I. Ruttenberg

Biological Sciences

We address the conflict in earlier results regarding the relationship between dispersal potential and range size. We examine all published pelagic larval duration data for tropical reef fishes. Larval duration is a convenient surrogate for dispersal potential in marine species that are sedentary as adults and that therefore only experience significant dispersal during their larval phase. Such extensive quantitative dispersal data are only available for fishes and thus we use a unique dataset to examine the relationship between dispersal potential and range size. We find that dispersal potential and range size are positively correlated only in the largest ocean basin, …

Phylogenetic History, Morphological Parallelism, And Speciation In A Complex Of Appalachian Salamanders (Genus: Desmognathus), Nathan D. Jackson

Theses and Dissertations

Understanding the mechanisms that generate shared morphologies across closely related taxa is important when identifying distinct evolutionary lineages using morphological characters. Desmognathus salamanders are an ideal group for testing hypotheses concerning the correlation between morphological similarity and genetic exchange within and among nominal species due to a pattern of high discordance between the two. Phylogeographic hypotheses are tested for populations of the D. quadramaculatus species complex throughout southern Appalachia by combining phylogenetic and population genetic methods with geographical information. Phylogenetic and phylogeographic inferences are then assessed in conjunction with morphological characteristics that have traditionally diagnosed taxonomic entities to understand the …

Investigations Of Migratory Bull Trout (Salvelinus Confluentus) In Relation To Fish Passage At Albeni Falls Dam, Allan T. Scholz, Holly J. Mclellan, David R. Geist, Richard S. Brown, United States Department Of The Army Corps Of Engineers, Seattle District, Eastern Washington University

Biology Faculty Publications

Final report prepared for the United States Department of the Army Corps of Engineers, Seattle District. Contract No. DACW68-02-D-001

Extrapair Fertilization And Genetic Similarity Of Social Mates In The Mexican Jay, John Eimes, Patricia Parker, Jerram Brown, Esther Brown

Biology Department Faculty Works

Inbreeding depression should favor the ability of females to avoid inbreeding or minimize its effects. We tested for a relationship between genetic similarity of social pairs and the occurrence of extrapair fertilization (EPF) in the Mexican jay (Aphelocoma ultramarina). Multilocus minisatellite and microsatellite DNA fingerprinting was used to detect extrapair young and measure genetic similarity between social parents. We found that 12 of 31 (39%) nests had at least one EPF and 15 of 93 (16%) young were the result of EPF. The mean DNA fingerprinting band sharing score between social mates who had at least one EPF was significantly …

Fitness Correlates Of Song Repertoire Size In Free-Living Song Sparrows (Melospiza Melodia), J. M. Reid, P. Arcese, A. L. E. V. Cassidy, Sara Hiebert Burch, J. N.M. Smith, P. K. Stoddard, A. B. Marr, L. F. Keller

Biology Faculty Works

Models of sexual selection propose that exaggerated secondary sexual ornaments indicate a male's own fitness and the fitness of his offspring. These hypotheses have rarely been thoroughly tested in free-living individuals because overall fitness, as opposed to fitness components, is difficult to measure. We used 20 years of data from song sparrows ( Melospiza melodia) inhabiting Mandarte Island, British Columbia, Canada, to test whether a male's song repertoire size, a secondary sexual trait, predicted overall measures of male or offspring fitness. Males with larger song repertoires contributed more independent and recruited offspring, and independent and recruited grandoffspring, to Mandarte's population. …

From The Cover: Assignment Of An Essential Role For The Neurospora Frequency Gene In Circadian Entrainment To Temperature Cycles, Antonio M. Pregueiro, Nathan Price-Lloyd, Deborah Bell-Pedersen, Christian Heintzen, Jennifer J. Loros, Jay C. Dunlap

Dartmouth Scholarship

Circadian systems include slave oscillators and central pacemakers, and the cores of eukaryotic circadian clocks described to date are composed of transcription and translation feedback loops (TTFLs). In the model system Neurospora, normal circadian rhythmicity requires a TTFL in which a White Collar complex (WCC) activates expression of the frequency (frq) gene, and the FRQ protein feeds back to attenuate that activation. To further test the centrality of this TTFL to the circadian mechanism in Neurospora, we used low-amplitude temperature cycles to compare WT and frq-null strains under conditions in which a banding rhythm was elicited. WT cultures were entrained …

Opinion: Avian Brains And A New Understanding Of Vertebrate Brain Evolution, Gerald E. Hough, The Avian Brain Nomenclature Consortium

College of Science & Mathematics Departmental Research

We believe that names have a powerful influence on the experiments we do and the way in which we think. For this reason, and in the light of new evidence about the function and evolution of the vertebrate brain, an international consortium of neuroscientists has reconsidered the traditional, 100-year-old terminology that is used to describe the avian cerebrum. Our current understanding of the avian brain — in particular the neocortex-like cognitive functions of the avian pallium — requires a new terminology that better reflects these functions and the homologies between avian and mammalian brains.

Hybrid Xerogel Films As Novel Coatings For Antifouling And Fouling Release, Ying Tang, John A. Finlay, Gregory L. Kowalke, Anne E. Meyer, Frank V. Bright, Maureen E. Callow, James A. Callow, Dean E. Wendt, Michael R. Detty

Biological Sciences

Hybrid sol-gel-derived xerogel films prepared from 45/55 (mol ratio) n-propyltrimethoxysilane (C3-TMOS)/tetramethylorthosilane (TMOS), 2/98 (mol ratio) bis[3-(trimethoxysilyl)propyl]-ethylenediamine (enTMOS)/tetraethylorthosilane (TEOS), 50/50 (mol ratio) n-octyltriethoxysilane (C8-TEOS)/TMOS, and 50/50 (mol ratio) 3,3,3-trifluoropropyltrimethoxysilane (TFP-TMOS)/TMOS were found to inhibit settlement of zoospores of the marine fouling alga Ulva (syn. Enteromorpha) relative to settlement on acid-washed glass and give greater release of settled zoospores relative to glass upon exposure to pressure from a water jet. The more hydrophobic 50/50 C8-TEOS/TMOS xerogel films had the lowest critical surface tension by comprehensive contact angle analysis and gave significantly greater release of 8-day Ulva sporeling biomass after exposure to …

Mechanisms For The Environmental Regulation Of Gene Expression: Ecological Aspects Of Animal Development, Scott F. Gilbert

Biology Faculty Works

The environment can play a significant role in the production of phenotypes. However, the developmental mechanisms by which the environmental agents effect normal development are Just becoming known. At least three paths have been found through which the environment can modify gene activity. The first is the neuroendocrine route. Here, the nervous system monitors the environment and transfers signals to the endocrine system. The endocrine hormones can then alter gene expression. The second route involves environmental factors that change the methylation pattern of genes, thereby altering their transcriptional capabilities. The third route involves the direct induction of gene expression in …

Elimination Of Foreign Dna During Somatic Differentiation In Tetrahymena Thermophila Shows Position Effect And Is Dosage Dependent, Yifan Liu, Xiaoyuan Song, Martin A. Gorovsky, Kathleen M. Karrer

Biological Sciences Faculty Research and Publications

In the ciliate Tetrahymena thermophila, approximately 15% of the germ line micronuclear DNA sequences are eliminated during formation of the somatic macronucleus. The vast majority of the internal eliminated sequences (IESs) are repeated in the micronuclear genome, and several of them resemble transposable elements. Thus, it has been suggested that DNA elimination evolved as a means for removing invading DNAs. In the present study, bacterial neo genes introduced into the germ line micronuclei were eliminated from the somatic genome. The efficiency of elimination from two different loci increased dramatically with the copy number of the neo genes in the …

The Genetics Of Ray Pattern Variation In Caenorhabditis Briggsae, Scott Everet Baird, Cynthia R. Davidson, Justin C. Bohrer

Biological Sciences Faculty Publications

Background: How does intraspecific variation relate to macroevolutionary change in morphology? This question can be addressed in species in which derived characters are present but not fixed. In rhabditid nematodes, the arrangement of the nine bilateral pairs of peripheral sense organs (rays) in tails of males is often the most highly divergent character between species. The development of ray pattern involves inputs from hometic gene expression patterns, TGFβ signalling, Wnt signalling, and other genetic pathways. In Caenorhabditis briggsae, strain-specific variation in ray pattern has provided an entrée into the evolution of ray pattern. Some strains were fixed for a derived …

Correlational Selection Leads To Genetic Integration Of Body Size And An Attractive Plumage Trait In Dark-Eyed Juncos, Joel Mcglothlin, Patricia Parker, Val Nolan, Ellen Ketterson

Biology Department Faculty Works

When a trait's effect on fitness depends on its interaction with other traits, the resultant selection is correlational and may lead to the integration of functionally related traits. In relation to sexual selection, when an ornamental trait interacts with phenotypic quality to determine mating success, correlational sexual selection should generate genetic correlations between the ornament and quality, leading to the evolution of honest signals. Despite its potential importance in the evolution of signal honesty, correlational sexual selection has rarely been measured in natural populations. In the dark‐eyed junco (Junco hyemalis), males with experimentally elevated values of a plumage trait (whiteness …

Effects Of Food Deprivation On Blood Lipid Concentration And Composition In Steller Sea Lions (Eumetopias Jubatus), Michelle Lea Berman

Electronic Theses and Dissertations

Steller sea lions, the largest Otariid, fast during their breeding season; during this time they refrain from ingesting food for a period of 12-43 days. Fasting, while undertaking an extremely energetically demanding activity (breeding and pupping), requires specific physiological adaptations. This study examined the physiological response to fasting of two age classes, juveniles and sub-adults, during the breeding and non-breeding seasons to determine how these animals utilize lipids and the pattern of fatty acid mobilization from lipid stores during fasting. Four juveniles and 5 sub-adults were fasted for one and two weeks, respectively, and blood samples were collected approximately every …

Responses Of The Florida Mouse (Podomys Floridanus) To Habitat Management, Jason Depue

Electronic Theses and Dissertations

The Florida mouse (Podomys floridanus), a species restricted to the Lake Wales Ridge and the Atlantic Coastal Ridge, is recognized by the Florida Fish and Wildlife Conservation Commission as a species of special concern, highlighting its status as a species that is threatened by habitat loss statewide. Publicly owned lands offer protection for the species, but management is generally focused on protecting biodiversity in general and not a particular species. The response of the Florida mouse to land management practices such as mechanical treatment and prescribed fires is poorly documented. This research examined the population responses of Florida mice on …