Life Sciences Commons^™

Positive Relationships Between Association Strength And Phenotypic Similarity Characterize The Assembly Of Mixed-Species Bird Flocks Worldwide, Hari Sridhar, Umesh Srinivasan, Robert A. Askins, Julio Cesar Canales-Delgadillo, Chao-Chieh Chen, David N. Ewert, George A. Gale, Eben Goodale, Wendy K. Gram, Patrick J. Hart, Keith A. Hobson, Richard L. Hutto, Sarath W. Kotagama, Jessie L. Knowlton, Tien Ming Lee, Charles A. Munn, Somchai Nimnuan, B. Z. Nizam, Guillaume Péron, V. V. Robin, Amanda D. Rodewald, Paul G. Rodewald, Robert L. Thomson, Pranav Trivedi, Steven L. Van Wilgenburg, Kartik Shanker

Biology Faculty Publications

Competition theory predicts that local communities should consist of species that are more dissimilar than expected by chance. We find a strikingly different pattern in a multicontinent data set (55 presence-absence matrices from 24 locations) on the composition of mixed-species bird flocks, which are important sub-units of local bird communities the world over. By using null models and randomization tests followed by meta-analysis, we find the association strengths of species in flocks to be strongly related to similarity in body size and foraging behavior and higher for congeneric compared with noncongeneric species pairs. Given the local spatial scales of our …

Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad

Biology Faculty Publications

Background: Over the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis).

Results: One mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an …

Idiosyncratic Responses Of Seagrass Phenolic Production Following Sea Urchin Grazing, Latina Steele, John F. Valentine

Biology Faculty Publications

While chemical defenses can determine plant persistence in terrestrial ecosystems and some marine macroalgae, their role in determining seagrass persistence in areas of intense grazing is unknown. As a first step toward determining if concentrations of feeding deterrents in seagrasses increase following herbivore attacks, we conducted 4 experiments using a common macrograzer (sea urchin Lytechinus variegatus) and 2 phylogenetically divergent seagrass species (Thalassia testudinum and Halodule wrightii). Macrograzer impacts on production of phenolic acids and condensed tannins varied somewhat idiosyncratically with season, urchin density, and distance from urchin damage. In general, phenolic concentrations were higher in both turtlegrass and shoalgrass …

The Development Of Dermatonotus Muelleri (Anura: Microhylidae: Gastrophryninae), Marissa Fabrezi, Silvia Quinzio, Javier Goldberg, Rafael O. De Sá

Biology Faculty Publications

The monophyly of Microhylidae is supported by an overwhelming accumulation of synapomorphic larval features. Despite the distinctiveness of the microhylid tadpole, few studies have focused on larval development. Microhylid larval morphology is usually described and based on standard tables that imply that developmental events at equivalent stages of overall tadpole development are independent from species-specific patterns of developmental timing. Herein, we present additional developmental data based on external morphology and field data on larval growth for the gastrophrynine microhylid Dermatonotus muelleri. We describe internal morphological variation (e.g., skeletal and soft systems) during larval development. The results indicate that the onset …

High Prevalence Of The Amphibian Chytrid Fungus (Batrachochytrium Dendrobatidis) Across Multiple Taxa And Localities In The Highlands Of Ethiopia, David J. Gower, Thomas M. Doherty-Bone, Roman K. Aberra, Abebe Mengistu, Silvia Schwaller, Michele Menegon, Rafael O. De Sá, Samy A. Saber, Andrew A. Cunningham, Simon P. Loader

Biology Faculty Publications

Surveys of the potentially lethal amphibian chytrid fungus (Batrachochytrium dendrobatidis - Bd) in Africa are patchy, especially in some regions of high species endemicity. We present results of the first Bd surveys of wild amphibians in Ethiopia, for two upland regions on either side of the Rift Valley: the Bale Mountains and the Kaffa region. Surveys were opportunistic so that robust interpretation of the data is limited. Utilizing diagnostic qPCR assays, 51 out of 120 frogs (14 species in 10 genera) tested positive for Bd at altitudes of 1,620–3,225 m, across all genera and species, and all but …

Effects Of Vegetation, Corridor Width And Regional Land Use On Early Successional Birds On Powerline Corridors, Robert A. Askins, Corrine M. Folsom-O'Keefe, Margaret C. Hardy

Biology Faculty Publications

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were

Leptodactylus Pentadactylus, Miriam M. Heyer, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus pentadactylus (Figure 1) are large, the head is about as wide as long, 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 not visible externally or are moderately expanded as a single sac. Sexually active males usually do not have hypertrophied forearms (the largest male examined, 195 mm SVL, has very weakly hypertrophied forearms), only the largest males have a single small to moderate size black spine on each thumb. No males have chest spines. Dorsolateral folds are …