Biology Commons^™

Water Availability Directly Determines Per Capita Consumption At Two Trophic Levels, Kevin E. Mccluney, John L. Sabo

Biological Sciences Faculty Publications

Community ecology has long focused on energy and nutrients as currencies of species interactions. Evidence from physiological ecology and recent studies suggest that in terrestrial systems, water may influence animal behavior and global patterns of species richness. Despite these observations, water has received little attention as a currency directly influencing animal species interactions. Here, we show that the per capita interaction strength between predatory wolf spiders and their primary prey, field crickets, is strong (0.266) when predators and prey are maintained in ambient dry conditions, but is near zero (0.001) when water is provided ad libitum. Moreover, crickets consume 31-fold …

Isolation Of Fungi From Lake Vostok Accretion Ice, Scott O. Rogers, Tom D'Elia, Ram Veerapaneni, Vincent Theraisnathan

Biological Sciences Faculty Publications

Here we report the characterization of fungi from 10 accretion ice sections (3300-5100 y old) as well as two deep glacial ice sections that are close to the bottom of the glacier (1 000 000-2 000 000 y old) from the Vostok, Antarctica, 5G ice core. Fungi were characterized by fluorescence microscopy culturing and sequence analyses of ribosomal DNA internal transcribed spacers. A total of 270 fungal colonies were cultured from the accretion ice of subglacial Lake Vostok and an additional 14 from the glacial ice immediately above the accretion ice. Mean concentrations were 0-4.42 cells mL-1 ice meltwater of …

Function, Regulation, And Transcriptional Organization Of The Hemin Utilization Locus Of Bartonella Quintana, Nermi L. Parrow, Jasmin Abbott, Amanda R. Lockwood, James M. Battisti, Michael F. Minnick

Biological Sciences Faculty Publications

Bartonella quintana is a gram-negative agent of trench fever, chronic bacteremia, endocarditis, and bacillary angiomatosis in humans. B. quintana has the highest known hemin requirement among bacteria, but the mechanisms of hemin acquisition are poorly defined. Genomic analyses revealed a potential locus dedicated to hemin utilization (hut) encoding a putative hemin receptor, HutA; a TonB-like energy transducer; an ABC transport system comprised of three proteins, HutB, HutC, and HmuV; and a hemin degradation/storage enzyme, HemS. Complementation analyses with Escherichia coli hemA show that HutA functions as a hemin receptor, and complementation analyses with E. coli hemA tonB indicate that HutA …

Fluctuating Asymmetry In Elk Cervus Elaphus Antlers Is Unrelated To Environmental Conditions In The Greater Yellowstone Ecosystem, Scott L. Eggeman, Mark Hebblewhite, Julie Cunningham, Ken Hamlin

Biological Sciences Faculty Publications

Fluctuating asymmetry (FA) is a measure of the deviation from perfect bilateral symmetry, and has been used across mammals as a reliable indicator of environmental stress during growth and development. Antler size and symmetry can be an indicator of individual fitness and social rank among ungulates such as the North American elk Cervus elaphus. When environmental conditions are favourable, ungulates allocate additional resources to antler development to increase secondary sexual traits and enhance reproduction. We tested whether there was an appreciable change in antler length and the number of points as extreme climatic conditions (e.g. heavy snow and drought) …

Tthe Immature Stages And Natural History Of Antirrhea Adoptiva Porphyrosticta (Watkins, 1928) In Eastern Ecuador (Lepidoptera, Nymphalidae, Morphinae), Harold F. Greeney, Philip J. Devries, Carla M. Penz, Rafael B. Granizo-T, Heidi Connahs, John O. Stireman Iii, Thomas R. Walla, Lee A. Dyer

Biological Sciences Faculty Publications

Here we describe the immature stages and ecological associations of Antirrhea adoptiva porphyrosticta Watkins, 1928 (Lepidoptera:Nymphalidae:Morphinae). The cloud forest bamboo, Chusquea scandens Kunth (Bambusoidea: Poaceae), serves as the larval food plant for this butterfly in eastern Ecuador, the first hostplant record for Antirrhea outside the family Arecaceae. The larvae of A. adoptiva porphyrosticta are superficially similar to those of other Antirrhea species. We also provide observations on adult and larval behavior. Caterpillars of this butterfly species are parasitized by tachinid flies, as well as by Ichneumonidae and a newly described braconid wasp.

Species Richness And Host Associations Of Lepidoptera-Attacking Tachinidae In The Northeast Ecuadorian Andes, John O. Stireman Iii, Harold F. Greeney, Lee A. Dyer

Biological Sciences Faculty Publications

Most of the unknown biological diversity of macro-organisms remaining to be discovered and described lies in the tropical regions of the world and consists primarily of insects. Those insects with parasitoid lifestyles constitute a significant portion of insect diversity, yet parasitoids are among the most poorly known of major insect guilds in the humid tropics. Here we describe and analyze the richness of one diverse taxon of parasitoids, flies in the family Tachinidae, reared from Lepidoptera as part of a biological survey of Lepidoptera and their parasitoids in one mid-elevation (2000 m) area in the northeast Ecuadorian Andes. One hundred …

Habitat Variation Among Aquatic Gastropod Assemblages Of Indiana, U.S.A., Mark Pyron, Jayson Beugly, Matthew Spielman, Jennifer Pritchett, Stephen J. Jacquemin

Biological Sciences Faculty Publications

We collected aquatic gastropods at 137 sites in lakes and streams of Indiana and tested for patterns of assemblages with environmental variables. The survey resulted in 32 species with a mean of 2.8 species at each site, and a mean abundance at each site of 144 individuals. Nonmetric multidimensional scaling (NMS) multivariate analyses resulted in watershed drainage area, water conductivity, substrate category frequency, and dissolved oxygen as significant correlates of gastropod assemblage structure. Gastropod assemblages of lakes were not significantly different than assemblages of streams in the ordination. Prosobranch taxa occurred in higher abundances than pulmonate taxa at sites with …

Genetic Variation At Hair Length Candidate Genes In Elephants And The Extinct Woolly Mammoth, Alfred L. Roca, Yasuko Ishida, Nikolaidis Sergios, Sergios-Orestis Kolokotronis, Stephen Fratpietro, Kristin Stewardson, Shannon Hensley, Michele Tisdale, Gennady Boeskorov, Alex D. Greenwood

Biological Sciences Faculty Publications

Background: Like humans, the living elephants are unusual among mammals in being sparsely covered with hair. Relative to extant elephants, the extinct woolly mammoth, Mammuthus primigenius, had a dense hair cover and extremely long hair, which likely were adaptations to its subarctic habitat. The fibroblast growth factor 5 (FGF5) gene affects hair length in a diverse set of mammalian species. Mutations in FGF5 lead to recessive long hair phenotypes in mice, dogs, and cats; and the gene has been implicated in hair length variation in rabbits. Thus, FGF5 represents a leading candidate gene for the phenotypic differences in hair length …

The Epidemiological Status Of Pav1, And The Effects Of Infection On Caribbean Spiny Lobster (Panulirus Argus) Condition, Olfaction, And Predation Risk, Donald C. Behringer, Mark J. Butler Iv, Jeffrey D. Shields

Biological Sciences Faculty Publications

No abstract provided.

Comparative Efficacy Of Bioud To Other Commercially Available Arthropod Repellants Against The Ticks Amblyomma Americanum And Dermacentor Variabilis On Cotton Cloth, Brooke W. Bissinger, Jiwei Zhu, Charles S. Apperson, Daniel E. Sonenshine, D. Wesley Watson, R. Michael Roe

Biological Sciences Faculty Publications

BioUD is an arthropod repellent that contains the active ingredient 2-undecanone originally derived from wild tomato plants. Repellency of BioUD was compared with five commercially available arthropod repellents against the ticks Amblyomma americanum (L.) and Dermacentor variabilis Say in two-choice bioassays on treated versus untreated cotton cheesecloth. Overall mean percentage repellency against both species was greatest for and did not differ significantly between BioUD (7.75% 2-undecanone) and products containing 98.1% DEET, 19.6% IR3535, and 30% oil of lemon eucalyptus. Products containing 5% and 15% Picaridin and 0.5% permethrin were also repellent compared with untreated controls but to a lesser degree …

The Ecological Importance Of Severe Wildfires: Some Like It Hot, Richard L. Hutto

Biological Sciences Faculty Publications

Many scientists and forest land managers concur that past fire suppression, grazing, and timber harvesting practices have created unnatural and unhealthy conditions in the dry, ponderosa pine forests of the western United States. Specifically, such forests are said to carry higher fuel loads and experience fires that are more severe than those that occurred historically. It remains unclear, however, how far these generalizations can be extrapolated in time and space, and how well they apply to the more mesic ponderosa pine systems and to other forest systems within the western United States. I use data on the pattern of distribution …

Optimality In A Partitioned Task Performed By Social Insects, Jerome J. Howard

Biological Sciences Faculty Publications

Biologists have long been aware that adaptations should not be analysed in isolation from the function of the whole organism. Here, we address the equivalent issue at the scale of a social insect colony: the optimality of component behaviours in a partitioned sequence of tasks. In colonies of Atta colombica, a leaf-cutting ant, harvested leaf tissue is passed from foragers to nest workers that distribute, clean, shred and implant the tissue in fungal gardens. In four laboratory colonies of A. colombica, we found that the highest colony-wide rate of leaf tissue processing in the nest was achieved when leaf fragment …

Ph-Induced Activation Of Arenavirus Membrane Fusion Is Antagonized By Small-Molecule Inhibitors, Joanne York, Dongcheng Dai, Sean M. Amberg, Jack H. Nunberg

Biological Sciences Faculty Publications

The arenavirus envelope glycoprotein (GPC) mediates viral entry through pH-induced membrane fusion in the endosome. This crucial process in the viral life cycle can be specifically inhibited in the New World arenaviruses by the small-molecule compound ST-294. Here, we show that ST-294 interferes with GPC-mediated membrane fusion by targeting the interaction of the G2 fusion subunit with the stable signal peptide (SSP). We demonstrate that amino acid substitutions at lysine-33 of the Junin virus SSP confer resistance to ST-294 and engender de novo sensitivity to ST-161, a chemically distinct inhibitor of the Old World Lassa fever virus. These compounds, as …

Recognition Of The Activated States Of Galpha13 By The Rgrgs Domain Of Pdzrhogef, Zhe Chen, William D. Singer, Shahab M. Danesh, Paul C. Sternweis, Stephen R. Sprang

Biological Sciences Faculty Publications

G12 class heterotrimeric G proteins stimulate RhoA activation by RGS-RhoGEFs. However, p115RhoGEF is a GTPase Activating Protein (GAP) toward Galpha13, whereas PDZRhoGEF is not. We have characterized the interaction between the PDZRhoGEF rgRGS domain (PRG-rgRGS) and the alpha subunit of G13 and have determined crystal structures of their complexes in both the inactive state bound to GDP and the active states bound to GDP*AlF (transition state) and GTPgammaS (Michaelis complex). PRG-rgRGS interacts extensively with the helical domain and the effector-binding sites on Galpha13 through contacts that are largely conserved in all three nucleotide-bound states, although PRG-rgRGS has highest affinity to …

Emerging Issues In Forensic Dna Profiling: Databases And Advisory Boards, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

Weed-Biocontrol Insects Reduce Native-Plant Recruitment Through Second-Order Apparent Competition, Dean E. Pearson, Ragan M. Callaway

Biological Sciences Faculty Publications

Small-mammal seed predation is an important force structuring native-plant communities that may also influence exotic-plant invasions. In the intermountain West, deer mice (Peromyscus maniculatus) are prominent predators of native-plant seeds, but they avoid consuming seeds of certain widespread invasives like spotted knapweed (Centaurea maculosa). These mice also consume the biological-control insects Urophora spp. introduced to control C. maculosa, and this food resource substantially increases deer mouse populations. Thus, mice may play an important role in the invasion and management of C. maculosa through food-web interactions. We examined deer mouse seed predation and its effects on …

Toxic Introns And Parasitic Intein In Coxiella Burnetii: Legacies Of A Promiscuous Past, Rahul Raghavan, Linda D. Hicks, Michael F. Minnick

Biological Sciences Faculty Publications

The genome of the obligate intracellular pathogen Coxiella burnetii contains a large number of selfish genetic elements, including two group I introns (Cbu.L1917 and Cbu.L1951) and an intervening sequence that interrupts the 23S rRNA gene, an intein (Cbu.DnaB) within dnaB and 29 insertion sequences. Here, we describe the ability of the intron-encoded RNAs (ribozymes) to retard bacterial growth rate (toxicity) and examine the functionality and phylogenetic history of Cbu.DnaB. When expressed in Escherichia coli, both introns repressed growth, with Cbu.L1917 being more inhibitory. Both ribozymes were found to associate with ribosomes of Coxiella and E. coli. In addition, ribozymes significantly …

Shifts In Southern Wisconsin Forest Canopy And Understory Richness, Composition, And Heterogeneity, David A. Rogers, Thomas P. Rooney, Daniel Olson, Donald M. Waller

Biological Sciences Faculty Publications

We resurveyed the under- and overstory species composition of 94 upland forest stands in southern Wisconsin in 2002–2004 to assess shifts in canopy and understory richness, composition, and heterogeneity relative to the original surveys in 1949–1950. The canopy has shifted from mostly oaks (Quercus spp.) toward more mesic and shade-tolerant trees (primarily Acer spp.). Oak-dominated early-successional stands and those on coarse, nutrient-poor soils changed the most in canopy composition. Understories at most sites (80%) lost native species, with mean species density declining 25% at the 1-m² scale and 23.1% at the 20-m² scale. Woody species have increased …

Ric-8a Catalyzes Guanine Nucleotide Exchange On G Alphai1 Bound To The Gpr/Goloco Exchange Inhibitor Ags3, Celestine J. Thomas, Gregory G. Tall, Anirban Adhikari, Stephen R. Sprang

Biological Sciences Faculty Publications

Microtubule pulling forces that govern mitotic spindle movement of chromosomes are tightly regulated by G-proteins. A host of proteins, including Galpha subunits, Ric-8, AGS3, regulators of G-protein signalings, and scaffolding proteins, coordinate this vital cellular process. Ric-8A, acting as a guanine nucleotide exchange factor, catalyzes the release of GDP from various Galpha.GDP subunits and forms a stable nucleotide-free Ric-8A:Galpha complex. AGS3, a guanine nucleotide dissociation inhibitor (GDI), binds and stabilizes Galpha subunits in their GDP-bound state. Because Ric-8A and AGS3 may recognize and compete for Galpha.GDP in this pathway, we probed the interactions of a truncated AGS3 (AGS3-C; containing only …

I. Vh Gene Transcription Creates Stabilized Secondary Structures For Coordinated Mutagenesis During Somatic Hypermutation, Barbara E. Wright, Karen H. Schmidt, Michael F. Minnick, Nick Davis

Biological Sciences Faculty Publications

During the adaptive immune response, antigen challenge triggers a million-fold increase in mutation rates in the variable-region antibody genes. The frequency of mutation is causally and directly linked to transcription, which provides ssDNA and drives supercoiling that stabilizes secondary structures containing unpaired, intrinsically mutable bases. Simulation analysis of transcription in VH5 reveals a dominant 65nt secondary structure in the non-transcribed strand containing six sites of mutable ssDNA that have also been identified independently in human B cell lines and in primary mouse B cells. This dominant structure inter-converts briefly with less stable structures and is formed repeatedly during transcription, due …

Ii. Correlations Between Secondary Structure Stability And Mutation Frequency During Somatic Hypermutation, Barbara E. Wright, Karen H. Schmidt, Nick Davis, Aaron T. Hunt, Michael F. Minnick

Biological Sciences Faculty Publications

The role of secondary structures and base mutability at different levels of transcription and supercoiling is analyzed in variable region antibody genes VH5, VH94 and VH186.2. The data are consistent with a model of somatic hypermutation in which increasing levels of transcription and secondary structure stability correlate with the initial formation of successive mutable sites. Encoded differences exist in stem length and the number of GC pairs at low versus high levels of transcription in CDRs. These circumstances simplify the complexities of coordinating mutagenesis by confining this process to each mutable site successively, as they form in response to increasing …

No Evidence For Trade-Offs: Centaurea Plants From America Are Better Competitors And Defenders, Wendy M. Ridenour, Jorge M. Vivanco, Yulong Feng, Jun-Ichiro Horiuchi, Ragan M. Callaway

Biological Sciences Faculty Publications

The natural enemies hypothesis has led to a number of ideas by which invaders might evolve superior competitive ability. In this context, we compared growth, reproduction, competitive effect, competitive response, and defense capabilities between invasive North American populations of Centaurea maculosa and populations in Europe, where the species is native. We found that Centaurea from North America were larger than plants from European populations. North American Centaurea also demonstrated stronger competitive effects and responses than European Centaurea. However, competitive superiority did not come at a cost to herbivore defense. North American plants were much better defended against generalist insect …

Lositan: A Workbench To Detect Molecular Adaptation Based On A Fst-Outlier Method, Tiago Antao, Ana Lopes, Ricardo J. Lopes, Albano Beja-Pereira, Gordon Luikart

Biological Sciences Faculty Publications

Background: Testing for selection is becoming one of the most important steps in the analysis of multilocus population genetics data sets. Existing applications are difficult to use, leaving many nontrivial, error-prone tasks to the user.

Results: Here we present LOSITAN, a selection detection workbench based on a well evaluated F_st-outlier detection method. LOSITAN greatly facilitates correct approximation of model parameters (e.g., genome-wide average, neutral F_st), provides data import and export functions, iterative contour smoothing and generation of graphics in a easy to use graphical user interface. LOSITAN is able to use modern multi-core processor architectures by …

Phytotoxic Effects Of (+/-)-Catechin In Vitro, In Soil, And In The Field, Inderjit, Jarrod L. Pollock, Ragan M. Callaway, William E. Holben

Biological Sciences Faculty Publications

Background: Exploring the residence time of allelochemicals released by plants into different soils, episodic exposure of plants to allelochemicals, and the effects of allelochemicals in the field has the potential to improve our understanding of interactions among plants. Methodology/Principal Findings: We conducted experiments in India and the USA to understand the dynamics of soil concentrations and phytotoxicity of (+/-)-catechin, an allelopathic compound exuded from the roots of Centaurea maculosa, to other plants in vitro and in soil. Experiments with single and pulsed applications into soil were conducted in the field. Experimental application of (+/-)-catechin to soils always resulted in concentrations …

Protecting Migration Corridors: Challenges And Optimism For Mongolian Saiga, Joel Berger, Julie K. Young, Kim Murray Berger

Biological Sciences Faculty Publications

No abstract provided.

Effects Of Native Species Diversity And Resource Additions On Invader Impact, John L. Maron, Marilyn Marler

Biological Sciences Faculty Publications

Theory and empirical work have demonstrated that diverse communities can inhibit invasion. Yet, it is unclear how diversity influences invader impact, how impact varies among exotics, and what the relative importance of diversity is versus extrinsic factors that themselves can influence invasion. To address these issues, we established plant assemblages that varied in native species and functional richness and crossed this gradient in diversity with resource (water) addition. Identical assemblages were either uninvaded or invaded with one of three exotic forbs: spotted knapweed (Centaurea maculosa), dalmatian toadflax (Linaria dalmatica), or sulfur cinquefoil (Potentilla recta). To determine impacts, we measured the …

Is The Effect Of Forest Structure On Bird Diversity Modified By Forest Productivity?, Jacob P. Verschuyl, Andrew J. Hansen, David B. Mcwethy, Rex Sallabanks, Richard L. Hutto

Biological Sciences Faculty Publications

Currently, the most common strategy when managing forests for biodiversity at the landscape scale is to maintain structural complexity within stands and provide a variety of seral stages across landscapes. Advances in ecological theory reveal that biodiversity at continental scales is strongly influenced by available energy (i.e., climate factors relating to heat and light and primary productivity). This paper explores how available energy and forest structural complexity may interact to drive biodiversity at a regional scale.

We hypothesized that bird species richness exhibits a hump-shaped relationship with energy at the regional scale of the northwestern United States. As a result, …

Undetected Species Losses, Food Webs, And Ecological Baselines: A Cautionary Tale From The Greater Yellowstone Ecosystem, Usa, Joel Berger

Biological Sciences Faculty Publications

Large protected areas are often considered natural yet outside pressures may compromise ecological integrity. This paper points to a problem in assessing ecological baselines: what if species' extirpations go undetected? I present a data set spanning 130 years that demonstrates the loss of white-tailed jack rabbits Lepus townsendii from two National Parks in the well studied 60,000 km(2) Greater Yellowstone Ecosystem, USA. While these extirpations have been unnoticed until now, an ecological consequence may be elevated predation on juvenile ungulates. A critical challenge we face is how to apply better the concept of shifting baselines to the restoration of functional …

Transient Elevation Of Corticosterone Alters Begging Behavior And Growth Of White-Crowned Sparrow Nestlings, Haruka Wada, Creagh W. Breuner

Biological Sciences Faculty Publications

Developing animals may face a cost–benefit tradeoff during growth mediated through hormones such as glucocorticoids, as the hormone is essential for development but can have detrimental consequences. To investigate potential tradeoffs caused by brief, moderate elevations of corticosterone in avian young, we artificially elevated the hormone levels in two ways: feeding corticosterone-containing worms and applying corticosterone dermal patches. The former experiment tested the effects of an acute corticosterone elevation (25 min) on begging behavior, whereas the latter explored the effects of artificially elevated corticosterone for 24 to 48 h on growth. Corticosterone altered both begging behavior and growth of white-crowned …

An Invader Differentially Affects Leaf Physiology Of Two Natives Across A Gradient In Diversity, Pamela Kittelson, John L. Maron, Marilyn Marler

Biological Sciences Faculty Publications

Little is known about how exotics influence the ecophysiology of co-occurring native plants or how invader impact on plant physiology may be mediated by community diversity or resource levels. We measured the effect of the widespread invasive forb spotted knapweed (Centaurea maculosa) on leaf traits (leaf dry matter content, specific leaf area, leaf nitrogen percentage, leaf C:N ratios, and δ¹³C as a proxy for water use efficiency) of two co-occurring native perennial grassland species, Monarda fistulosa (bee balm) and Koeleria macrantha (Junegrass). The impact of spotted knapweed was assessed across plots that varied in functional diversity …