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Articles 151 - 180 of 402

Full-Text Articles in Biology

Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson May 2007

Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

Natural history researchers are increasingly using digital cameras and computer software to measure their study animals. Adult Red-spotted Newts (Notophthalmus viridescens viridescens) are known to display a range of skin colors, from brown to green, but it has not been possible to quantify this variation until the advent of image analysis technology. We used an image analysis approach to compare skin color between sexes, across a range of sizes, and between aquatic and post-breeding (emigrating to the terrestrial habitat) stage adult newts. From 232 individuals (53% male, 47% female) we documented a wide but subtle range of skin …

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The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá May 2007

The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá

Biology Faculty Publications

The genus Eupsophus is characterized by endotrophic larvae that inhabit water-filled cavities. The larvae feed from large yolk reserves during metamorphosis. The external morphology has been described for four of the ten known species and data on larval chondrocranial morphology are available only for one. We describe the extema1 morphology, oral disc and chondrocranial anatomy of the larvae of Eupsophus queulensis. The characteristics of E. queulensis tadpoles are compared with those of other Eupsophus larvae.

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The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla Apr 2007

The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus notoaktites Heyer, 1978, are described and illustrated for Gosner’s stage 33. The internal oral anatomy was analyzed under SEM at Gosner’s stage 36 whereas chondrocranial anatomy is reported for Gosner’ stage 38. The morphology of this tadpole is compared with those available for other species of the L. mystaceus complex. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the fuscus species group. The labial tooth row formula is 2(2)/3.

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Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe Jan 2007

Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe

Biology Faculty Publications

Funnel traps of various designs have been used to capture adults and larvae of aquatic amphibians (e.g., Buech and Egeland 2002; Richter 1995). Most studies use unbaited funnel traps to capture amphibians while others have used shrimp or salmon eggs (Adams et al. 1997). Light traps and light sticks are commonly used in studies of fish, particularly larvae (Doherty 1987; Marchetti et al. 2004), but have not been widely used to capture amphibians. Glow sticks have been mentioned briefly in the literature as a means to increase capture rates of aquatic amphibians (Smith and Rettig 1996), but no studies have …

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Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá Dec 2006

Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus validus has an unusual distribution, inhabiting Trinidad, Tobago, and the Lesser Antilles, but not the mainland of South America. This distribution is inconsistent with other distribution patterns observed for these islands. Although slight variation in adult morphology has been observed among the different island populations of L. validus, call data suggest the presence of a single species. Calls of L. pallidirostris from Venezuela and Brazil suggested that this taxon might be conspecific with L. validus. Sequence data from the 12S and 16S mt rDNA genes indicate that L. validus represents a single species throughout its distribution and is conspecific …

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Karyotypes Of Eight Species Of Leptodactylus (Anura, Leptodactylidae) With A Description Of A New Karyotype For The Genus, Renata Cecília Amaro-Ghilardi, Gabriel Skuk, Rafael O. De Sá, Miguel Trefaut Rodrigues, Yatiyo Yonenaga-Yassuda Dec 2006

Karyotypes Of Eight Species Of Leptodactylus (Anura, Leptodactylidae) With A Description Of A New Karyotype For The Genus, Renata Cecília Amaro-Ghilardi, Gabriel Skuk, Rafael O. De Sá, Miguel Trefaut Rodrigues, Yatiyo Yonenaga-Yassuda

Biology Faculty Publications

Karyotypes of eight species of Leptodactylus (Anura, Leptodactylidae) with a description of a new karyotype for the genus. Eight species of the Neotropical genus Leptodactylus were karyologically studied: seven of them (L. gracilis, L. mystacinus, L. petersii, L. pustulatus, L. macrosternum, L. ocellatus, L. labyrinthicus) presented 2n=22 and L. silvanimbus showed a distinctive karyotype with 2n=24. Nucleolar organizer regions (Ag-NORs) were detected in two different pairs of chromosomes: pair 4 at the proximal region of the long arm of one individual of L. mystacinus from São Paulo state and of L. petersii; and …

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Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá Sep 2006

Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá

Biology Faculty Publications

The purpose of this application, under Article 75.6 of the Code, is to conserve the usage of the specific name of Rana ocellata Linnaeus, 1758 for a species of leptodactylid frog from South America by the designation of a neotype. Prevailing usage of the name is threatened by the identity of the type specimen which is a different species than that which is currently known as Leptodactylus ocellatus. It is proposed that all name-bearing types be set aside and a neotype designated in accord with prevailing usage.

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The Distress Calls Of Leptodactylus Chaquensis Cei, 1950 And Leptodactylus Elenae Heyer, 1978 (Anura: Leptodactylidae), José M. Padial, Rafael O. De Sá, Ignacio De La Riva Feb 2006

The Distress Calls Of Leptodactylus Chaquensis Cei, 1950 And Leptodactylus Elenae Heyer, 1978 (Anura: Leptodactylidae), José M. Padial, Rafael O. De Sá, Ignacio De La Riva

Biology Faculty Publications

We describe the distress calls of Leptodactylus chaquensis and Leptodactylus elenae. They each consist of a single, long, tonal sound with complex harmonic structure and complex frequency modulation. The distress calls of both species are different from their respective advertisement calls. Moreover, there are also clear interspecific differences. Harmonic frequencies in L. elenae are higher, there are fewer emphasized harmonics and the call is shorter and repeated at a higher rate (sometimes paired) than the call of L. chaquensis. Call duration, call rate, and position of the dominant harmonic change with the strength of the stimulus that the …

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Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer Feb 2006

Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer

Biology Faculty Publications

Leptodactylus fuscus is a neotropical frog ranging from Panamá to Argentina, to the east of the Andes mountains, and also inhabiting Margarita, Trinidad, and the Tobago islands. We performed phylogenetic analyses of 12S rRNA, 16S rRNA, tRNA-Leu, and ND1 mitochondrial (mt) DNA sequences from specimens collected across the geographic distribution of L. fuscus to examine two alternative hypotheses: (i) L. fuscus is a single, widely distributed species, or (ii) L. fuscus is a species complex. We tested statistically for geographic association and partitioning of genetic variation among mtDNA clades. The mtDNA data supported the hypothesis of several cryptic species within …

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The Effect Of Tgf-B And Egf On Mmp-2 Activation And Mt1-Mmp Phosphorylation In U87mg And T98g Human Glioma Cells, Jacquelyn B. Knupp Jan 2006

The Effect Of Tgf-B And Egf On Mmp-2 Activation And Mt1-Mmp Phosphorylation In U87mg And T98g Human Glioma Cells, Jacquelyn B. Knupp

Honors Theses

Glioblastoma multiforme (GBM), a high-grade, malignant brain tumor of astrocyte origin, invades normal brain tissue and most often results in death ofthe patient withinayearofdiagnosis. In order to invade the surrounding tissue and thereby metastasize, these tumor cells must migrate through the extracellular matrix. The pmpose ofthis research project is to investigate the family ofmatrix metalloproteinases responsible for extracellular degradation. Specifically, this investigation looks at MMP-2 activation via MT 1-MMP and the possible importance of phosphorylation of the tyrosine residue on the cytoplasmic tail of MTl-MMP. U87wildtypegliomacellsaswellasT98 p53 mutant glioma cells were treated with transforming growth factor beta (TGF-P). Preliminary results …

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Development Of Proliferation Assays To Explore The Role Of Calcium Activated Potassium Channels In Cell Proliferation, Sean Foster Jan 2006

Development Of Proliferation Assays To Explore The Role Of Calcium Activated Potassium Channels In Cell Proliferation, Sean Foster

Honors Theses

Due to the large variety of K† channel families implicated in cancer cell proliferation, it is desirable to develop techniques capable of quickly and reliably screening a variety of potential channels for a role in proliferation. While there are many established cell counting procedures, the time-consuming nature of such protocols limits their usefulness in broadly identifying particular channels in uncharacterized cell lines. For this reason, a primary goal of the present research was the development of techniques capable of implicating particular ion channels in proliferation with both qualitative and quantitative data. Once this goal was accomplished, the project sought …

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The Amphibian Tree Of Life, Darrel R. Frost, Taran Grant, Julián Faivovich, Raoul H. Bain, Alexander Haas, Célio F.B. Haddad, Rafael O. De Sá Jan 2006

The Amphibian Tree Of Life, Darrel R. Frost, Taran Grant, Julián Faivovich, Raoul H. Bain, Alexander Haas, Célio F.B. Haddad, Rafael O. De Sá

Biology Faculty Publications

The evidentiary basis of the currently accepted classification of living amphibians is discussed and shown not to warrant the degree of authority conferred on it by use and tradition. A new taxonomy of living amphibians is proposed to correct the deficiencies of the old one. This new taxonomy is based on the largest phylogenetic analysis of living Amphibia so far accomplished. We combined the comparative anatomical character evidence of Haas (2003) with DNA sequences from the mitochondrial transcription unit H1 (12S and 16S ribosomal RNA and tRNAValine genes, ø 2,400 bp of mitochondrial sequences) and the nuclear genes histone H3, …

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The Effects Of P53 Status And Egf On Timp-2 And Other Proteins Related To Migration In Human Glioblastoma Cell Cultures, Lisa M. Lint Jan 2006

The Effects Of P53 Status And Egf On Timp-2 And Other Proteins Related To Migration In Human Glioblastoma Cell Cultures, Lisa M. Lint

Honors Theses

The effects of epidermal growth factor (EGF) on proteins that have been implicated in the migration of the Grade IV brain tumor, glioblastoma multiforme, were investigated in this study. Differential expression levels of TIMP-2, MMP-2, and MT1-MMP in response to EGF treatment were compared by immunoprecipitation, and immunoblotting. This study involved two different cultured glioma cell lines, U87, which expresses wild-type p53, and T98, which has a mutation in the p53 gene, in order to determine if the status of the p53 tumor suppression gene is a factor in the regulation of proteins involved in this migration pathway. It was …

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The Presence, Prevalence And Antibiotic Resistance Of Microbes In The Pamunkey River Basin, Christina Mcdowell Jan 2006

The Presence, Prevalence And Antibiotic Resistance Of Microbes In The Pamunkey River Basin, Christina Mcdowell

Honors Theses

This project examined the presence, prevalence and antibiotic resistance of Coliforms (mainly Escherichia coli), Staph/occocus aureus, fecal Streptococcus, andEnterobacteriacae found in the water samples taken from three selected sites on the North Anna, South Anna, and Little Rivers of the Pamunkey River Basin. The diversity and concentration of the microbes isolated from these sites was evaluated in late January and late March allowing for a comparison of the occurrence of microbes at different times and between the different sites. Over the course of two months the concentration of colonies increased based on colony counts from Nutrient agar. The rate of …

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Leptodactylus Fragilis (Brocchi): White-Lipped Thin-Toed Frog, Miriam M. Heyer, W. Ronald Heyer, Rafael O. De Sá Jan 2006

Leptodactylus Fragilis (Brocchi): White-Lipped Thin-Toed Frog, Miriam M. Heyer, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus fragilis are small. The head is longer than wide, and the hind limbs are moderately long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are laterally expanded and range from lightly gray speckled to darkly pigmented. Male snout is spatulate; female snout is rounded. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is spotted or blotched with dark markings, which are often chevron-shaped and sometimes confluent. The supratympanic fold is dark brown. A pair of dorsolateral folds …

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Leptodactylus Fragilis, Mirriiam Muedeking Heyer, W. Ronald Heyer, Rafael O. De Sá Jan 2006

Leptodactylus Fragilis, Mirriiam Muedeking Heyer, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus fragilis (Brocchi) White-lipped thin-toed frogs are characteristically defined according to their habitation and age. There is a diagnosis of different species group within Leptodactylus. It is furthermore described from different perspectives and discoveries such as its eggs and karyotype. The distribution of the frog is considered to be prominent occurring form Southernmost Teaxs throughout Mexico and Middle America expanding to Venezuela. The fossil fuel records and literature on Leptodactylus are slighly viewed before studying its nomenclatural history and rarity.

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Redescripción De La Morfología Larval Externa De Dos Especies Del Grupo De Leptodactylus Fuscus (Anura, Leptodactylidae), José A. Langone, Rafael O. De Sá Oct 2005

Redescripción De La Morfología Larval Externa De Dos Especies Del Grupo De Leptodactylus Fuscus (Anura, Leptodactylidae), José A. Langone, Rafael O. De Sá

Biology Faculty Publications

Re-description of the larval external morphology of two species of the Leptodactylus fuscus group (Anura, Leptodactylidae). The larvae of Leptodactylus gracilis (D’Orbigny y Bibron, 1840) and L. mystacinus Bumeister, 1861 are re-described and compared with previous descriptions noting intraspecific variation in oral disc characteristics (arrangement of papillae and rows of cornified teeth). The external morphological analysis of larvae of the Leptodactylus fuscus group suggest that the lack of comparable descriptions among species, as well as the lack of analyses of their intraspecific variation, limits the use of larval characteristics for diagnostic purposes.

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A Phylogenetic Analysis Of Vanzolinius Heyer, 1974 (Amphibia, Anura, Leptodactylidae): Taxonomic And Life History Implications, Rafael O. De Sá, W. Ronald Heyer, Arley Camargo Oct 2005

A Phylogenetic Analysis Of Vanzolinius Heyer, 1974 (Amphibia, Anura, Leptodactylidae): Taxonomic And Life History Implications, Rafael O. De Sá, W. Ronald Heyer, Arley Camargo

Biology Faculty Publications

The validity of the monotypic leptodactylid frog genus Vanzolinius Heyer, 1974 has been questioned recently. We explore the relationship of Vanzolinius discodactylus within the cluster of closely related genera Adenomera, Leptodacylus, and Lithodytes with both morphological and molecular data sets. Morphological and combined morphological and molecular data were analyzed using maximum parsimony; molecular data sets were analyzed with maximum likelihood methods. The resultant relationships are unambiguous in Vanzolinius being imbedded within Leptodactylus. In order to maintain Leptodactylus as a monophyletic genus, Vanzolinius is placed in the synonymy of Leptodactylus Fitzinger, 1826. The implications of relationships analyzed in …

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An Investigation Of The Changes Of Species Richness And Distribution Of The Unionidae (Bivalvia: Molusca) Within The Pamunkey Watershed, William Robert Lees Sep 2005

An Investigation Of The Changes Of Species Richness And Distribution Of The Unionidae (Bivalvia: Molusca) Within The Pamunkey Watershed, William Robert Lees

Master's Theses

A survey of the Unionidae within the Pamunkey Watershed was conducted to investigate changes in distribution and species richness compared to a previous survey (Riddick, 1973) conducted over 30 years ago. Species richness decreased from 10 species in the previous survey to four species in the present survey. Notable increases of species richness were found in the upper South Anna and the lower North Anna regions, while sizable decreases were found in the lower South Anna and the upper and middle regions of the Pamunkey River. Regression analyses and t-tests comparing mussel survey data with habitat parameters were conducted to …

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"Sibling Species, Advertisement Calls, And Reproductive Isolation In Frogs Of The Leptodactylus Pentadactylus Species Cluster (Amphibia, Leptodactylidae), W. Ronald Heyer, Rafael O. De Sá, A. Rettig Aug 2005

"Sibling Species, Advertisement Calls, And Reproductive Isolation In Frogs Of The Leptodactylus Pentadactylus Species Cluster (Amphibia, Leptodactylidae), W. Ronald Heyer, Rafael O. De Sá, A. Rettig

Biology Faculty Publications

A recent re-evaluation of morphological and advertisement call variation in the large species of frogs of the Leptodactylus pentadactylus cluster discovered more examples of sibling species as defined by Ernst Mayr in his influential book Animal Species and Evolution. All previously documented instances of sibling species in frogs demonstrated advertisement call differentiation consistent with the calls serving as pre-mating isolating mechanisms. However, we find one instance of two species with nondistinguishable adult morphologies as well as nondistinguishable advertisement calls. Presumably, the new instances of sibling species reflect retention of ancestral adult morphologies and advertisement calls. Larval and habitat differentiation appear …

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The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry Jan 2005

The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry

Master's Theses

The project was undertaken with three main goals in mind: to provide as current and complete an account as possible of the flora of Powhatan County in the form of an annotated checklist; to integrate the information obtained from the inventory into phytogeographical and ecological generalizations currently being developed for the state of Virginia; and, to report any significant or anomalous discoveries. There is no previous county-wide inventory of plant diversity for Powhatan County. However, Corcoran (1981) published a list of plants from the Jones and Mill Creek watershed located in the Fine Creek Mills area of northeastern Powhatan.

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Cytokine Expression By T. Helper Cells Responding To Stress, Dina Zanetti Jan 2005

Cytokine Expression By T. Helper Cells Responding To Stress, Dina Zanetti

Master's Theses

Stress causes alterations to the immune system. These alterations have lead to increased susceptibility to antigens. The present study explores shifts in T helper (TH) cell balance (TH1 and TH2), through their cytokine expression. This study was performed in three phases, and focused mainly on animals subjected to a 10 day a chronic unpredictable stress paradigm. Phase one used ELISAs to confirm the cytokine profile produced from TH 1 and TH2 murine cell-lines. Phase two used SDS PAGE and Western Immunoblotting to show that splenocytes from Long Evan's Hooded rats subjected to the stress paradigm, had decreased in intercellular in …

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Common Names For The Frog Genus Leptodactylus (Amphibia, Anura, Leptodactylidae), Ulisses Caramaschi, Rafael O. De Sá, W. Ronald Heyer Jan 2005

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 …

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

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 …

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Invertebrate Diversity In Taylor Valley Soils And Sediments, Amy M. Treonis, Diana H. Wall, Ross A. Virginia Jan 2005

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 …

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Are Leptodactylus Didymus And L. Mystaceus Phylogenetically Sibling Species (Amphibia, Anura, Leptodactylidae)?, Rafael O. De Sá, W. R. Heyer, A. Camargo Jan 2005

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 …

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On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller Jan 2005

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 …

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Are Leptodactylus Didymus And L. Mystaceus Phylogenetically Sibling Species (Amphibia, Anura, Leptodactylidae)?, Rafael O. De Sá, W. R. Heyer, Arley Camargo Jan 2005

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 …

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Common Names For The Frog Genus Leptodactylus (Amphibia, Anura, Leptodactylidae), Ulisses Caramaschi, Rafael O. De Sá, W. Ronald Heyer Jan 2005

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 …

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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 Dec 2004

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 …

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