Life Sciences Commons^™

Body Size, Energy Use, And Community Structure Of Small Mammals, S.K. Morgan Ernest

Biology Faculty Publications

Body size has long been hypothesized to play a major role in community structure and dynamics. Two general hypotheses exist for how resources are distributed among body sizes: (1) resources are equally available and uniformly utilized across body sizes and (2) resources are differentially available to organisms of different body sizes, resulting in a nonuniform or modal distribution. It has also been predicted that the distri-bution of body sizes of species in a community should reflect the underlying availability of resources, with the emergence of aggregations of species around specific body sizes. I examined the relationship between energy utilization, body …

2005 Virginia Wildflower Of The Year: Bloodroot, Sanguinaria Canadensis, W. John Hayden

Biology Faculty Publications

Bloodroot is an herbaceous perennial that grows from a persistent, branched underground stem or rhizome. Early each spring, while the forest canopy is still bare, each well-developed rhizome tip produces one leaf and one flower stalk. The leaf is kidney-shaped in its overall outline, but it is also divided into a pattern of rounded lobes and sinuses, rendering a complex overall shape. At flowering time, bloodroot leaves form a loose vertically-oriented collar around the flower stalk with the bluish-green lower leaf surface forming the outside of the collar; as the season progresses, the leaves open flat and expand to their …

Common Names For The Frog Genus Leptodactylus (Amphibia, Anura, Leptodactylidae), Ulisses Caramaschi, Rafael O. De Sá, W. Ronald Heyer

Biology Faculty Publications

Most species of the frog genus Leptodactylus lack common names. Common names are those names used by different human cultures and societies for the species of animals and plants where humans and biota reside together. Often times common names are lacking for Neotropical frogs or are broad in scope. For example, indigenous people may have a single name for frogs that occur on the ground and another name for frogs that occur in shrubs and trees, even though there are many species of ground frogs called by the same name as well as for the tree frogs. Sometimes colonists have …

Are Leptodactylus Didymus And L. Mystaceus Phylogenetically Sibling Species (Amphibia, Anura, Leptodactylidae)?, Rafael O. De Sá, W. R. Heyer, Arley Camargo

Biology Faculty Publications

The Leptodactylus fuscus species group consists of 25 currently recognized species; within this species group and distributed throughout the Amazon Basin, Atlantic Forests, Gran Chaco, and cerrados is the L. mystaceus species complex. This species complex consists of L. didymus, L. elenae, L. mystaceus, L. notoaktites, and L. spixi. Adult morphologies have been used to distinguish these species from each other except for L. didymus and L. mystaceus (Heyer, 1978; Heyer et al., 1996). Leptodactylus didymus and L. mystaceus are morphologically indistinguishable; the species are recognizable only by the characteristics of their advertisement calls: non-pulsed in L. didymus and pulsed …

Plant Composition Of Mixed-Grass Prairie Of Cedar Point Biological Research Station, Keith County, Nebraska, David A. Mckenzie

Biology Faculty Publications

This study involved a vegetation analysis of 15 permanent plots established on the short-grass and mixed grass prairie slopes at the Cedar Point Biological Station in Keith County, Nebraska. Ninety-nine species were found in the plots, including members of 75 genera and 31 families. Twenty-one were graminoids, 71 were forbs or succulents, 6 were shrubs and one was a tree. Bouteloua gracilis (19 % cover) and Carex filifolia (15 % cover) were the dominant graminoids at the site, while Yucca glauca (1% cover) and Artemisia frigida (1% cover) were the most frequent forbs. Comparisons of species richness by slope categories …

Controls On Nitrogen Cycling In Terrestrial Ecosystems: A Synthetic Analysis Of Literature Data, M. S. Booth, E. Rastetter, John M. Stark

Biology Faculty Publications

Isotope pool dilution studies are increasingly reported in the soils and ecology literature as a means of measuring gross rates of nitrogen (N) mineralization, nitrification, and inorganic N assimilation in soils. We assembled data on soil characteristics and gross rates from 100 studies conducted in forest, shrubland, grassland, and agricultural systems to answer the following questions: What factors appear to be the major drivers for production and consumption of inorganic N as measured by isotope dilution studies? Do rates or the relationships between drivers and rates differ among ecosystem types? Across a wide range of ecosystems, gross N mineralization is …

Common Names For The Frog Genus Leptodactylus (Amphibia, Anura, Leptodactylidae), Ulisses Caramaschi, Rafael O. De Sá, W. Ronald Heyer

Biology Faculty Publications

Most species of the frog genus Leptodactylus lack common names. Common names are those names used by different human cultures and societies for the species of animals and plants where humans and biota reside together. Often times common names are lacking for Neotropical frogs or are broad in scope. For example, indigenous people may have a single name for frogs that occur on the ground and another name for frogs that occur in shrubs and trees, even though there are many species of ground frogs called by the same name as well as for the tree frogs. Sometimes colonists have …

Invertebrate Diversity In Taylor Valley Soils And Sediments, Amy M. Treonis, Diana H. Wall, Ross A. Virginia

Biology Faculty Publications

Explaining how ecosystems function across variable landscapes will require knowledge of biodiversity patterns. In particular, biodiversity studies of soils and sediments will help in understanding the linkages between ecosystem processes in both of these habitats (Freckman et al. 1997). Soils and sediments are domains for ecosystem processes such as decomposition and trace gas exchange. There are few studies, however, that have compared abundance and diversity of organisms in adjacent soils and sediments (Freckman et al. 1997). The goal of this study was to increase understanding of how the biotic communities involved in ecosystem processes are organized within an important feature …

Crisis Global De Biodiversidad: Importancia De La Diversidad Genética Y La Extinción De Anfibios, Rafael O. De Sá

Biology Faculty Publications

El mundo enfrenta, por primera vez desde el comienzo de la civilización, el declive y la extinción de una clase de vertebrados, los anfibios. Esta extinción aparenta ser un evento global y de la magnitud que llevó a la desaparición de los dinosaurios. Muchas son las posibles causas de esta extinción y el efecto combinado de estos factores agravan la situación. La pérdida de ambientes naturales permanece como el factor más crítico en el declive de anfibios, pero enfermedades infecciosas emergentes parecen ser responsables de mortalidades masivas en décadas recientes. El declive y extinción de anfibios representa una llamada urgente …

Are Leptodactylus Didymus And L. Mystaceus Phylogenetically Sibling Species (Amphibia, Anura, Leptodactylidae)?, Rafael O. De Sá, W. R. Heyer, A. Camargo

Biology Faculty Publications

The Leptodactylus fuscus species group consists of 25 currently recognized species; within this species group and distributed throughout the Amazon Basin, Atlantic Forests, Gran Chaco, and cerrados is the L. mystaceus species complex. This species complex consists of L. didymus, L. elenae, L. mystaceus, L. notoaktites, and L. spixi. Adult morphologies have been used to distinguish these species from each other except for L. didymus and L. mystaceus (Heyer, 1978; Heyer et al., 1996). Leptodactylus didymus and L. mystaceus are morphologically indistinguishable; the species are recognizable only by the characteristics of their advertisement calls: non-pulsed in L. didymus and pulsed …

On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller

Biology Faculty Publications

Most species of the frog genus Leptodactylus occur in South America, and all authors who have treated the zoogeography of the genus have concluded that it originated somewhere in South America (e.g., Savage 1982). Savage (1982,518) summarized the historical herpetofaunal units of the Neotropics as follows: "All evidence points to an ancient contiguity and essential similarity of a generalized tropical herpetofauna that ranged over tropical North, Middle, and most of South America in Cretaceous-Paleocene times. Descendents of this fauna are represented today by the South and Middle American tracks (Elements). To the north of this fauna ranged a subtropical-temperate Laurasian …

The Challenge Of Environmental Protection, Jennifer Mattei

Biology Faculty Publications

Connecticut is in the midst of a demographic transition to a period of lower population growth. These demographic changes will help check the pressures exerted on the state's natural resources by population growth. Water, air, soil, energy sources, food, fisheries, forests, and biodiversity are common pool resources upon which we depend in ways that transcend political boundaries. Those governing Connecticut should help turn the state into a model of how to manage natural resources by halting forest fragmentation, reducing pollution, and promoting environmental science education.

Effect Of Dietary Fatty Acid Composition On Depot Fat And Exercise Performance In A Migrating Songbird, The Red-Eyed Vireo, Barbara J. Pierce, Scott R. Mcwilliams, Timothy P. O'Connor, Allen R. Place, Christopher G. Guglielmo

Biology Faculty Publications

Most migrating birds accumulate lipid stores as their primary source of energy for fueling long distance flights. Lipid stores of birds during migration are composed of mostly unsaturated fatty acids; whether such a fatty acid composition enhances exercise performance of birds is unknown. We tested this hypothesis by measuring metabolic rate at rest and during intense exercise in two groups of red-eyed vireos, a long-distance migratory passerine, fed either a diet containing 82% unsaturated fat (82%U), or one containing 58% unsaturated fat (58%U). Vireos fed the 82%U diet had fat stores containing (77%) unsaturated fatty acids, whereas vireos fed the …

Phylogenetic Relationships Of African Microhylid Frogs Inferred From Dna Sequences Of Mitochondrial 12s And 16s Rrna Genes, Simon P. Loader, David J. Gower, Kim M. Howell, Nike Doggart, Mark-Oliver Rödel, Barry T. Clarke, Rafael O. De Sá, Bernard L. Cohen, Mark Wilkinson

Biology Faculty Publications

The phylogenetic relationships of microhylid frogs are poorly understood. The first molecular phylogeny for continental African microhylids is presented, including representatives of all subfamilies, six of the eight genera, and the enigmatic hemisotid Hemisus. Mitochondrial 12S and 16S rRNA sequence data were analysed using parsimony, likelihood and Bayesian methods. Analyses of the data are consistent with the monophyly of all sampled subfamilies and genera. Hemisus does not nest within either brevicipitines or non-brevicipitines. It is possibly the sister group to brevicipitines, in which case brevicipitines might not be microhylids. Phrynomantis and Hoplophryne potentially group with non-African, non-brevicipitine microhylids, in …

Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie

Biology Faculty Publications

No abstract provided.

Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Planting Date Effects On The Germinability And Seedling Vigor Of Abutilon Theophrasti Seeds, R E. Nurse, A Ditommaso, Ricardo A. Ramirez

Biology Faculty Publications

Abutilon theophrasti (Malvaceae) is a troublesome annual weed in many maize and soybean cropping systems of Canada and the United States. Seeds of A. theophrasti exhibit physical dormancy. Differences in the growing environment of parent plants may influence the germinability of seeds and vigour of seedlings produced by this species because of variation in resource allocation to seed development. Thus, the germinability of seeds and subsequent seedling vigour were examined for A. theophrasti plants grown in monoculture at a density of 4.2 plants m -2 under varying natural photoperiods in central New York State. Treatments were established by transplanting A. …

Apparent Sibling Rivalry In The Freshwater Clam Sphaerium Striatinum, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

In Sphaerium striatinum, a freshwater brooding bivalve, up to 97.5% of offspring that adults initially produce fail to reach independence. Marsupial sacs, specialized extensions of gill filaments that act as nurseries, initially contain multiple offspring in various sizes and stages of development. However, by the time offspring reach later stages of development, marsupial sacs typically contain only one offspring. Brood mortality is hypothesized to be the result of competition among embryos for nutrients and/or space. Sphaeriid eggs do not contain enough yolk for offspring to complete development. Adults supply additional nutrients required to reach independence. Brood capacity is limited by …

Two Drosophila Suppressors Of Cytokine Signaling (Socs) Differentially Regulate Jak And Egfr Pathway Activities, Jason S. Rawlings, Gabriela Rennebeck, Susan M.W. Harrison, Rongwen Xi, Douglas A. Harrison

Biology Faculty Publications

BACKGROUND: The Janus kinase (JAK) cascade is an essential and well-conserved pathway required to transduce signals for a variety of ligands in both vertebrates and invertebrates. While activation of the pathway is essential to many processes, mutations from mammals and Drosophila demonstrate that regulation is also critical. The SOCS (Suppressor Of Cytokine Signaling) proteins in mammals are regulators of the JAK pathway that participate in a negative feedback loop, as they are transcriptionally activated by JAK signaling. Examination of one Drosophila SOCS homologue, Socs36E, demonstrated that its expression is responsive to JAK pathway activity and it is capable of downregulating …

Growth Of Stygobitic (Orconectes Australis Packardi) And Epigean (Orconectes Cristavarius) Crayfishes Maintained In Laboratory Conditions, Ann-Simone Cooper, Robin L. Cooper

Biology Faculty Publications

This study reports on maintenance and growth of the cave crayfish, Orconectes australis packardi, and the epigean crayfish, Orconectes cristavarius, with laboratory conditions for 1 and 2 years. The O. a. packardi survived well compared to the O. cristavarius in captivity. The poor survival of the epigean species was probably due to unsuitable conditions. The epigean as well as the cave crayfish molted and grew in captivity, but without any significant difference in molt frequency between species. In the first year, total body length was obtained to assay growth, whereas in the second year the more accurate measure …

The Bvg Virulence Control System Regulates Biofilm Formation In Bordetella Bronchiseptica, Yasuhiko Irie, Seema Mattoo, Ming H. Yuk

Biology Faculty Publications

Bordetella species utilize the BvgAS (Bordetella virulence gene) two-component signal transduction system to sense the environment and regulate gene expression among at least three phases: a virulent Bvg⁺ phase, a nonvirulent Bvg⁻ phase, and an intermediate Bvgⁱ phase. Genes expressed in the Bvg⁺ phase encode known virulence factors, including adhesins such as filamentous hemagglutinin (FHA) and fimbriae, as well as toxins such as the bifunctional adenylate cyclase/hemolysin (ACY). Previous studies showed that in the Bvgⁱ phase, FHA and fimbriae continue to be expressed, but ACY expression is significantly downregulated. In this report, we determine …

Zebra Mussels Affect Benthic Predator Foraging Success, Mark Beekey, D. J. Mccabe, I. E. Marsden

Biology Faculty Publications

The introduction of zebra mussels (Dreissena spp.) to North America has resulted in dramatic changes to the complexity of benthic habitats. Changes in habitat complexity may have profound effects on predator-prey interactions in aquatic communities. Increased habitat complexity may affect prey and predator dynamics by reducing encounter rates and foraging success. Zebra mussels form thick contiguous colonies on both hard and soft substrates. While the colonization of substrata by zebra mussels has generally resulted in an increase in both the abundance and diversity of benthic invertebrate communities, it is not well known how these changes affect the foraging efficiencies of …

From Biomedicine To Natural History Research: Est Resources For Ambystomatid Aalamanders, Srikrishna Putta, Jeramiah J. Smith, John A. Walker, Mathieu Rondet, David W. Weisrock, James Monaghan, Amy K. Samuels, D. Kevin Kump, David C. King, Nicholas J. Maness, Bianca Habermann, Elly Tanaka, Susan V. Bryant, David M. Gardiner, David M. Parichy, S. Randal Voss

Biology Faculty Publications

BACKGROUND: Establishing genomic resources for closely related species will provide comparative insights that are crucial for understanding diversity and variability at multiple levels of biological organization. We developed ESTs for Mexican axolotl (Ambystoma mexicanum) and Eastern tiger salamander (A. tigrinum tigrinum), species with deep and diverse research histories.

RESULTS: Approximately 40,000 quality cDNA sequences were isolated for these species from various tissues, including regenerating limb and tail. These sequences and an existing set of 16,030 cDNA sequences for A. mexicanum were processed to yield 35,413 and 20,599 high quality ESTs for A. mexicanum and A. t. tigrinum, respectively. Because the …

Integrating Research And Teaching Labs With The Module Evolution Approach, Michael S. Reagan

Biology Faculty Publications

No abstract provided.

A New Toad (Anura: Bufonidae) From Uruguay, Raúl Maneyro, Diego Arrieta, Rafael O. De Sá

Biology Faculty Publications

A new species of toad is described from small streams in the hills of Cuchilla de Haedo and Cuchilla Grande in northeastern Uruguay. Specimens of the new species were previously mistaken for Bufo arenarum; they differ from B.arenarum by having elongated parotoid glands and reddish-brown parotoid and cephalic crests. A discriminant analysis resulted in three groups corresponding to B. arenarum, Bufo rufus, and the specimens herein described as a new species.

A New Species Of Callulina (Anura: Microhylidae) From The West Usambara Mountains, Tanzania, Rafael O. De Sá, Simon P. Loader, Alan Channing

Biology Faculty Publications

The description of the species Callulina kreffti was based on specimens collected in the East Usambara Mountains of Tanzania. Successive collecting has shown this species to be widely distributed through the Eastern Arc Mountains. Advertisement calls from populations in the type locality of Callulina kreffti were compared with calls from populations in the West Usambara Mountains. Analysis of the calls suggested that these two populations of Callulina represent two separate taxa. Subsequent morphological and molecular investigations indicated that these two populations are distinct. Herein, we describe a new Callulina species on the basis of call, morphology and molecular sequences.

Drosophila As An Emerging Model To Study Metastasis, Madhuri Kango-Singh, Georg Halder

Biology Faculty Publications

Metastasis is the primary cause of human cancer-related deaths. Two recent studies describe a system for testing how multiple genetic events synergize to promote neoplastic growth and metastasis in Drosophila, paving the way for systematic approaches to understanding metastasis using the powerful tools of Drosophila genetics.

Phylogenetic Signal And The Utility Of 12s And 16s Mtdna In Frog Phylogeny, S. Hertwig, Rafael O. De Sá, A. Haas

Biology Faculty Publications

Genes selected for a phylogenetic study need to contain conserved information that reflects the phylogenetic history at the specific taxonomic level of interest. Mitochondrial ribosomal genes have been used for a wide range of phylogenetic questions in general and in anuran systematics in particular. We checked the plausibility of phylogenetic reconstructions in anurans that were built from commonly used 12S and 16S rRNA gene sequences. For up to 27 species arranged in taxon sets of graded inclusiveness, we inferred phylogenetic hypotheses based on different apriori decisions, i.e. choice of alignment method and alignment parameters, including/excluding variable sites, choice of reconstruction …

Seed Mass And Morphology In Outcrossing And Selfing Species Of Clarkia (Onagraceae): An Sem Study, Jennifer L. Knies, Veronique A. Delesalle, A. R. Cavaliere

Biology Faculty Publications

Seeds from three pairs of outcrossing-selfing sister taxa from the genus Clarkia (farewell-to-spring, Onagraceae)—Clarkia unguiculata, Clarkia exilis, Clarkia xantiana ssp. xantiana and ssp. parviflora, and Clarkia concinna ssp. concinna and ssp. automixa—were studied to assess the effects of contrasting mating systems on seed mass and seed morphology. For each outcrossing-selfing comparison, the seed mass of the selfing taxon was less than that of the outcrossing taxon. Seed mass typically differed significantly among populations within a taxon. Scanning electron microscopy showed that the seeds from all these taxa share several characteristics: a bullet to shield shape, a reticulate exotesta pattern, presence …