Life Sciences Commons^™

Giants Among Micromorphs: Were Cincinnatian (Ordovician, Katian) Small Shelly Phosphatic Faunas Dwarfed?, Benjamin F. Dattilo, Rebecca L. Freeman, Winfried S. Peters, William P. Heimbrock, Bradley Deline, Anthony J. Martin, Jack W. Kallmeyer, Jesse Reeder, Anne Argast

Winfried S. Peters

Using Gis Mapping Of The Extent Of Nearshore Rocky Reefs To Estimate The Abundance And Reproductive Output Of Important Fishery Species, Jeremy Claisse, Daniel Pondella, Jonathan Williams, James Sadd

James Sadd

Kelp Bass (Paralabrax clathratus) and California Sheephead (Semicossyphus pulcher) are economically and ecologically valuable rocky reef fishes in southern California, making them likely indicator species for evaluating resource management actions. Multiple spatial datasets, aerial and satellite photography, underwater observations and expert judgment were used to produce a comprehensive map of nearshore natural rocky reef habitat for the Santa Monica Bay region (California, USA). It was then used to examine the relative contribution of individual reefs to a regional estimate of abundance and reproductive potential of the focal species. For the reefs surveyed for fishes (i.e. 18 …

Elevated Co2 Induced Changes In The Chemistry Of Quaking Aspen (Populus Tremuloides Michaux) Leaf Litter: Subsequent Mass Loss And Microbial Response In A Stream Ecosystem, Steven Rier, Nancy Tuchman, Robert Wetzel, James Teeri

Nancy Tuchman

No abstract provided.

An Annotated Bibliography Of References To Historical Distributions Of Pronghorn In Southern And Baja California, David Brown, Jorge Cancino, Kevin Clark, Myrna Smith, Jim Yoakum

David C. Brown

Recent pronghorn (Antilocapra americana) translocations to southern California and the establishment of captive populations of endangered desert pronghorn have revived interest in the historical occurrence of pronghorn in the Californias. Adding to this interest is the recent widespread replacement of coastal sage scrub vegetation in southern California by annual grasslands more favorable to pronghorn. We have searched the scientific and popular literature, as well as museum collections, to locate pronghorn antelope occurrences from below San Francisco Bay southward through the Baja California peninsula. Our results show that pronghorn were widely distributed, and often abundant, on nearly all of the plains …

Advancing Synthetic Ecology: Database System To Facilitate Complex Ecological Meta-Analyses, V. Bala Chaudhary

V. Bala Chaudhary

No abstract provided.

Untangling The Biological Contributions To Soil Stability In Semiarid Shrublands, V. Bala Chaudhary, Matthew Bowker, Thomas O'Dell, James Grace, Andrea Redman, Mathias Rillig, Nancy Johnson

V. Bala Chaudhary

Communities of plants, biological soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence soil stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities at 216 locations along a gradient of soil stability levels in southern Utah, USA. We used multivariate modeling to examine the relative influences of plants, BSCs, and AM fungi on surface and subsurface stability in a semiarid shrubland landscape. Models were found to be congruent with the data and explained …

Mysterious Mycorrhizae? A Field Trip And Classroom Experiment To Demystify The Symbioses Formed Between Plants And Fungi, Nancy Johnson, V. Bala Chaudhary, Jason Hoeksema, John Moore, Anne Pringle

V. Bala Chaudhary

No abstract provided.

A Re-Assessment Of Priority Amphibian Species Of Peru, Edgar Lehr, Laurence Jarvis, Ariadne Angulo, Alessandro Catenazzi, Rudolf Von May, Jason Brown, James Lewis

Edgar Lehr

Peru supports approximately 588 amphibian species, of which 492 have been assessed on the IUCN Red List of Threatened Species. Of these, 111 are classified as Threatened, with 69 species classified as Critically Endangered or Endangered. In addition, 140 amphibian species remain Data Deficient. We re-assessed the conservation status of 38 amphibian species originally identified as potentially Threatened by von May et al. (2008), using the IUCN Red List Categories and Criteria. Fourteen species assessments changed as a result of re-assessment, of which eight changed from Data Deficient to Threatened; two changed from Data Deficient to Near Threatened and Least …

Cannibalism Causes Size-Dependent Intraspecific Predation Pressure But Does Not Trigger Autotomy In The Intertidal Gastropod Agaronia Propatula, Ariel Z. Cyrus, Jennifer Swiggs, Pilar Santidrian Tomillo, Frank V. Paladino, Winfried S. Peters

Winfried S. Peters

Positive Selection Drives Preferred Segment Combinations During Influenza Virus Reassortment, Konstantin Zeldovich, Ping Liu, Nicholas Renzette, Matthieu Foll, Serena Pham, Sergey Venev, Glen Gallagher, Daniel Bolon, Evelyn Kurt-Jones, Jeffrey Jensen, Daniel Caffrey, Celia Schiffer, Timothy Kowalik, Jennifer Wang, Robert Finberg

Celia A. Schiffer

Influenza A virus (IAV) has a segmented genome that allows for the exchange of genome segments between different strains. This reassortment accelerates evolution by breaking linkage, helping IAV cross species barriers to potentially create highly virulent strains. Challenges associated with monitoring the process of reassortment in molecular detail have limited our understanding of its evolutionary implications. We applied a novel deep sequencing approach with quantitative analysis to assess the in vitro temporal evolution of genomic reassortment in IAV. The combination of H1N1 and H3N2 strains reproducibly generated a new H1N2 strain with the hemagglutinin and nucleoprotein segments originating from H1N1 …

Drug-Resistant Hiv-1 Protease Regains Functional Dynamics Through Cleavage Site Coevolution, Nevra Ozer, Aysegul Ozen, Celia Schiffer, Turkan Haliloglu

Celia A. Schiffer

Drug resistance is caused by mutations that change the balance of recognition favoring substrate cleavage over inhibitor binding. Here, a structural dynamics perspective of the regained wild-type functioning in mutant HIV-1 proteases with coevolution of the natural substrates is provided. The collective dynamics of mutant structures of the protease bound to p1-p6 and NC-p1 substrates are assessed using the Anisotropic Network Model (ANM). The drug-induced protease mutations perturb the mechanistically crucial hinge axes that involve key sites for substrate binding and dimerization and mainly coordinate the intrinsic dynamics. Yet with substrate coevolution, while the wild-type dynamic behavior is restored in …

Project-Based Collaborative Innovation For The Igeneration, James Gerry, Carl Heine

Carl Heine

Social media provides powerful opportunities to create new learning communities. Online, project-based activities reach today's iGen students in ways they learn best, maximizing interaction and individualization through the use of free Web technologies such as CoolHub.IMSA. Discover ways to use networing tools to transform teaching and learning at your school.

Eurycea Guttolineata, Travis Ryan, Brittney Douthitt

Travis J. Ryan

Species account in Amphibian Declines: The Conservation Status of United States Species. M. J. Lannoo, ed. University of California Press, Berkeley, CA.

Eurycea Junaluska, Geoffrey Hammerson, Travis Ryan

Travis J. Ryan

Assessment of the Junaluska salamander in regard to its threatened status.

The Larvae Of Eurycea Junaluska (Amphibia: Caudata: Plethodontidae), With Comments On Distribution, Travis Ryan

Travis J. Ryan

Travis J. Ryan's shorter contribution to Copeia 1997.

Does Sex Influence Post-Reproductive Metamorphosis In Ambystoma Talpoideum?, Travis Ryan, Gabrielle Swenson

Travis J. Ryan

Shorter communication in the Journal of Herpetology v. 35.

Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis Ryan, Raymond Semlitsch

Travis J. Ryan

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced …

Evaporative Water Loss In Two Natricine Snakes, Nerodia Fasciata And Seminatrix Pygaea, Christopher Winne, Travis Ryan, Yale Leiden, Michael Dorcas

Travis J. Ryan

Shorter communication in Journal of Herpetology v. 35.

Aspects Of Sex-Specific Differences In The Expression Of An Alternative Life Cycle In The Salamander Ambystoma Talpoideum, Christopher Winne, Travis Ryan

Travis J. Ryan

A recent evolutionary ecological model of facultative paedomorphosis predicts that body size of mature individuals should be larger than immatures of the same cohort. We investigated sex-specific differences in body size and maturation within a single cohort of branchiate (= larval and paedomorphic) mole salamanders, Ambystoma talpoideum. In addition, we also sampled the population after the breeding season, as some individuals began to undergo metamorphosis and leave the pond. The branchiate population was female-biased (62.7%), and mature (paedomorphic) females were significantly smaller than paedomorphic males or immature (larval) females. The majority of male branchiates were mature (86.6%), whereas significantly fewer …

Life History Evolution And Adaptive Radiation Of Hemidactyliine Salamanders, Travis Ryan, R. Bruce

Travis J. Ryan

T.J. Ryan and R.C. Bruce's contribution to: The Biology of Plethodontid Salamanders, R. C. Bruce, R. G. Jaeger, and L. D. Houck, eds. Kluwer Academic/Plenum Publishers, New York.

Stereochilus Marginatus, Travis Ryan

Travis J. Ryan

Species account in Amphibian Declines: The Conservation Status of United States Species. M. J. Lannoo, ed. University of California Press, Berkeley, CA.

Sex And Size Interaction And Standard Metabolic Rate Of Paedomorphic Ambystoma Talpoideum: Size Does Matter, Travis Ryan, William Hopkins

Travis J. Ryan

We measured the standard metabolic rate of paedomorphic Mole Salamanders (Ambystoma talpoideum) from South Carolina. Despite an absence of body size differences between females and males, analysis of covariance demonstrated metabolic rates (mL O2/h) were significantly influenced by an interaction between sex and body size. The interaction appeared as a result of changes in the size-metabolism relationship in males (a steeper slope in the size-metabolism regression in small males as compared to large males), whereas the relationship remained constant in females, regardless of size. We hypothesize that the observed differences are attributable to differences in reproductive physiology between the sexes. …

Larval Life History And Abundance Of A Rare Salamander, Eurycea Junaluska (Plethodontidae), Travis Ryan

Travis J. Ryan

The larval life history of Eurycea junaluska was studied in three southwestern North Carolina populations. Populations were sampled quarterly over a 13 mo period and size-class analyses were used to evaluate the pattern of larval growth and metamorphosis. Young of the year appeared in the late spring and experienced rapid growth through the first summer. Growth slowed in the second year and metamorphosis usually occured in the summer at about 25.5 mo post-hatching, although some data suggest that either 1yr or 3yr larval periods may be possible. The overall larval growth rate of E. junaluska is estimated at 1.27 mm/mo, …

Influenza Virus Drug Resistance: A Time-Sampled Population Genetics Perspective, Matthieu Foll, Yu Poh, Nicholas Renzette, Anna Admetlla, Claudia Bank, Hyunjin Shim, Anna Malaspinas, Gregory Ewing, Ping Liu, Daniel Wegmann, Daniel Caffrey, Konstantin Zeldovich, Daniel Bolon, Jennifer Wang, Timothy Kowalik, Celia Schiffer, Robert Finberg, Jeffrey Jensen

Celia A. Schiffer

The challenge of distinguishing genetic drift from selection remains a central focus of population genetics. Time-sampled data may provide a powerful tool for distinguishing these processes, and we here propose approximate Bayesian, maximum likelihood, and analytical methods for the inference of demography and selection from time course data. Utilizing these novel statistical and computational tools, we evaluate whole-genome datasets of an influenza A H1N1 strain in the presence and absence of oseltamivir (an inhibitor of neuraminidase) collected at thirteen time points. Results reveal a striking consistency amongst the three estimation procedures developed, showing strongly increased selection pressure in the presence …

Connecting Through Consilience: Ecology, Society, Culture And Technology, Ruth Mirams, Alexander Hayes

Alexander Hayes Mr.

Amongst linguistic, cultural and geographic diversity, humanity is characterised by inquisitiveness, communication and a deep desire to connect with each other. Despite our advanced intelligence and technological capacity, we are creatures of nature - a species which occupies a habitat, depends on consumable resources and fragile in many ways. As a species, we currently face challenges including overpopulation, diminishing resources and habitat degradation. In essence, we are exhausting the resources we depend on. [1] Resource depletion, disruption, famine, growth and sustainability are all observable in other species and natural systems. Human societies and systems can be described through the same …

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters

Benjamin F. Dattilo

The Orientation Of Strophomenid Brachiopods On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Daniel Piquard, Jennifer Bauer, Joshua Corrie

Benjamin F. Dattilo

Strophomenid brachiopods have long been interpreted as ‘‘snowshoe’’ strategists, with their flattened concavoconvex valves providing resistance to foundering in very soft sediments. There has been a sharp difference of opinion in whether the shells were oriented with their convex or their concave surface in contact with the sediment. This study, along with independent evidence from sedimentology, ichnology, and morphology, indicates that the strophomenids lived with their shells concave down (convex up). Experiments indicate the force required to push shells into soft cohesive muds is much greater for the convex up than for the convex down orientation. Forces also increase with …

Willingness To Pay For Flood And Ecological Risk Reduction In An Urban Watershed, David Clark, Diane Novotny, Robert Griffin, Douglas Booth, Alena Bartosova, M Hutchinson

Robert Griffin

Urban watershed managers frequently must address alternative policy goals; flood control and ecological risk reduction. This study combines hydrologic models of flood control and biotic models of ecologic risk with economic models of willingness-to-pay and psychological models of risk processing and planned behavior to evaluate these two alternative policy objectives. The findings reveal that flood risk exposure, especially for those individuals who would remain outside the 100 year flood plain if the project were enacted, does influence the financial support that local residents would be willing to make to a flood control project. Other important determinants include demographic factors such …

The Cannibalistic Snail Agaronia Propatula Is Reluctant To Feed On Autotomized ‘Tails’ Of Conspecifics, Ariel Z. Cyrus, Winfried S. Peters

Winfried S. Peters

The First Molecular Phylogeny Of Buthidae (Scorpiones), Victor Fet, Benjamin Gantenbein, Alexander Gromov, Graeme Lowe, Wilson Lourenço

Victor Fet

The first partial phylogeny of family Buthidae (17 genera) is presented, based on molecular data (16S rRNA mitochondrial DNA). The strong support for a monophyletic Old World group of 13 genera (mainly Palearctic desert forms) is demonstrated, while representative genera from Madagascar (Grosphus) and Southeast Asia (Lychas) group outside, as well as New World genera Centruroides and Rhopalurus. A very strong support is observed for the first time for three groups of Old World genera: (a) Compsobuthus, Mesobuthus, Liobuthus, Kraepelinia; (b) Hottentotta, Buthacus; (c) Orthochirus, Anomalobuthus. Phylogenetic hypotheses are discussed.