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A Transgenic Marker For Newly Born Granule Cells In Dentate Gyrus, Linda S. Overstreet, Shane T. Hentges, Viviana F. Bumaschny, Flavio S.J. De Souza, James L. Smart, Andrea M. Santangelo, Malcolm J. Low, Gary L. Westbrook, Marcelo Rubinstein Mar 2004

A Transgenic Marker For Newly Born Granule Cells In Dentate Gyrus, Linda S. Overstreet, Shane T. Hentges, Viviana F. Bumaschny, Flavio S.J. De Souza, James L. Smart, Andrea M. Santangelo, Malcolm J. Low, Gary L. Westbrook, Marcelo Rubinstein

Faculty Publications - Department of Biological & Molecular Science

Neurogenesis in the dentate gyrus continues into adulthood, yet little is known about the function of newly born neurons or how they integrate into an existing network of mature neurons. We made transgenic mice that selectively and transiently express enhanced green fluorescent protein (EGFP) in newly born granule cells of the dentate gyrus under the transcriptional control of proopiomelanocortin (POMC) genomic sequences. Analysis of transgenic pedigrees with truncation or deletion mutations indicated that EGFP expression in the dentate gyrus required cryptic POMC promoter regions dispensable for arcuate hypothalamic or pituitary expression. Unlike arcuate neurons, dentate granule cells did not express …

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Spatial Heterogeneity Of Crenarchaeal Assemblages Within Mesophilic Soil Ecosystems As Revealed By Pcr-Single-Stranded Conformation Polymorphism Profiling, Marek K. Sliwinski Mar 2004

Spatial Heterogeneity Of Crenarchaeal Assemblages Within Mesophilic Soil Ecosystems As Revealed By Pcr-Single-Stranded Conformation Polymorphism Profiling, Marek K. Sliwinski

Faculty Work

Microbial ecologists have discovered novel rRNA genes (rDNA) in mesophilic soil habitats worldwide, including sequences that affiliate phylogenetically within the division Crenarchaeota (domain Archaea). To characterize the spatial distribution of crenarchaeal assemblages in mesophilic soil habitats, we profiled amplified crenarchaeal 16S rDNA sequences from diverse soil ecosystems by using PCR-single-stranded-conformation polymorphism (PCR-SSCP) analysis. PCR-SSCP profiles provide a measure of relative microbial diversity in terms of richness (number of different phylotypes as estimated from the number of unique PCR-SSCP peaks) and evenness (abundance of each phylotype as estimated from the relative area under a peak). Crenarchaeal assemblages inhabiting prairie, forest, …

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A Dominant-Negative Fur Mutation In Bradyrhizobium Japonicum, Heather P. Benson, Kristin Levier, Mary Lou Guerinot Mar 2004

A Dominant-Negative Fur Mutation In Bradyrhizobium Japonicum, Heather P. Benson, Kristin Levier, Mary Lou Guerinot

Dartmouth Scholarship

In many bacteria, the ferric uptake regulator (Fur) protein plays a central role in the regulation of iron uptake genes. Because iron figures prominently in the agriculturally important symbiosis between soybean and its nitrogen-fixing endosymbiont Bradyrhizobium japonicum, we wanted to assess the role of Fur in the interaction. We identified a fur mutant by selecting for manganese resistance. Manganese interacts with the Fur protein and represses iron uptake genes. In the presence of high levels of manganese, bacteria with a wild-type copy of the furgene repress iron uptake systems and starve for iron, whereas fur mutants fail to …

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2-O-Methylation Of Fucosyl Residues Of A Rhizobial Lipopolysaccharide Is Increased In Response To Host Exudate And Is Eliminated In A Symbiotically Defective Mutant, K. Dale Noel, Jodie M. Box, Valerie J. Boone Mar 2004

2-O-Methylation Of Fucosyl Residues Of A Rhizobial Lipopolysaccharide Is Increased In Response To Host Exudate And Is Eliminated In A Symbiotically Defective Mutant, K. Dale Noel, Jodie M. Box, Valerie J. Boone

Biological Sciences Faculty Research and Publications

When Rhizobium etli CE3 was grown in the presence of Phaseolus vulgaris seed extracts containing anthocyanins, its lipopolysaccharide (LPS) sugar composition was changed in two ways: greatly decreased content of what is normally the terminal residue of the LPS, di-O-methylfucose, and a doubling of the 2-O-methylation of other fucose residues in the LPS O antigen. R. etli strain CE395 was isolated after Tn5 mutagenesis of strain CE3 by screening for mutant colonies that did not change antigenically in the presence of seed extract. The LPS of this strain completely lacked 2-O-methylfucose, regardless of whether anthocyanins …

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Seasonal Use Of Bridges By Rafinesque's Big-Eared Bat, Corynorhinus Rafinesquii, In Southern Mississippi, Austin W. Trousdale, David C. Beckett Mar 2004

Seasonal Use Of Bridges By Rafinesque's Big-Eared Bat, Corynorhinus Rafinesquii, In Southern Mississippi, Austin W. Trousdale, David C. Beckett

Faculty Publications

We conducted surveys of concrete bridges in southern Mississippi from 2000–2002 to determine the phenological pattern of use by Rafinesque's big-eared bat, Corynorhinus rafinesquii. The earliest dates on which we located maternity colonies were 9 March 2000, 20 April 2001, and 15 May 2002. Maternity colonies increased in size and abundance as spring progressed. Pups were born in mid- to late May (first observed 12 May 2000, 15 May 2001, 27 May 2002) and nursed through midsummer (lactating females last captured 14 July 2000, 25 July 2001, 16 July 2002). Colony size and percentage of bridges occupied by bats declined …

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Bacterial Succession In A Petroleum Land Treatment Unit, Christopher W. Kaplan, Christopher L. Kitts Mar 2004

Bacterial Succession In A Petroleum Land Treatment Unit, Christopher W. Kaplan, Christopher L. Kitts

Biological Sciences

Bacterial community dynamics were investigated in a land treatment unit (LTU) established at a site contaminated with highly weathered petroleum hydrocarbons in the C(10) to C(32) range. The treatment plot, 3,000 cubic yards of soil, was supplemented with nutrients and monitored weekly for total petroleum hydrocarbons (TPH), soil water content, nutrient levels, and aerobic heterotrophic bacterial counts. Weekly soil samples were analyzed with 16S rRNA gene terminal restriction fragment (TRF) analysis to monitor bacterial community structure and dynamics during bioremediation. TPH degradation was rapid during the first 3 weeks and slowed for the remainder of the 24-week project. A sharp …

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In Situ Cardiac Performance Of Pacific Bluefin Tuna Hearts In Response To Acute Temperature Change, Jason M. Blank, Jeffery M. Morrissette, Ana M. Landeira-Fernandez, Susanna B. Blackwell, Thomas D. Williams, Barbara A. Block Feb 2004

In Situ Cardiac Performance Of Pacific Bluefin Tuna Hearts In Response To Acute Temperature Change, Jason M. Blank, Jeffery M. Morrissette, Ana M. Landeira-Fernandez, Susanna B. Blackwell, Thomas D. Williams, Barbara A. Block

Biological Sciences

This study reports the cardiovascular physiology of the Pacific bluefin tuna (Thunnus orientalis) in an in situ heart preparation. The performance of the Pacific bluefin tuna heart was examined at temperatures from 30°C down to 2°C. Heart rates ranged from 156 beats min–1 at 30°C to 13 beats min–1 at 2°C. Maximal stroke volumes were 1.1 ml kg–1 at 25°C and 1.3 ml kg–1 at 2°C. Maximal cardiac outputs were 18.1 ml kg–1 min–1 at 2°C and 106 ml kg–1 min–1 at 25°C. These data indicate that cardiovascular function in …

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Mer1p Is A Modular Splicing Factor Whose Function Depends On The Conserved U2 Snrnp Protein Snu17p, Marc Spingola, Javier Armisen, Manuel Ares Feb 2004

Mer1p Is A Modular Splicing Factor Whose Function Depends On The Conserved U2 Snrnp Protein Snu17p, Marc Spingola, Javier Armisen, Manuel Ares

Biology Department Faculty Works

Mer1p activates the splicing of at least three pre‐mRNAs (AMA1, MER2, MER3) during meiosis in the yeast Saccharomyces cerevisiae. We demonstrate that enhancer recognition by Mer1p is separable from Mer1p splicing activation. The C‐terminal KH‐type RNA‐binding domain of Mer1p recognizes introns that contain the Mer1p splicing enhancer, while the N‐terminal domain interacts with the spliceosome and activates splicing. Prior studies have implicated the U1 snRNP and recognition of the 5′ splice site as key elements in Mer1p‐activated splicing. We provide new evidence that Mer1p may also function at later steps of spliceosome assembly. First, Mer1p can activate splicing of introns …

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Variation In Vasotocin Immunoreactivity In The Brain Of Recently Isolated Populations Of A Death Valley Pupfish, Cyprinodon Nevadensis, Sean C. Lema, Gabrielle A. Nevitt Feb 2004

Variation In Vasotocin Immunoreactivity In The Brain Of Recently Isolated Populations Of A Death Valley Pupfish, Cyprinodon Nevadensis, Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region of California and Nevada comprise a monophyletic group of populations that became isolated in remote streams and springs over the past 20,000 years. These aquatic habitats show considerable ecological diversity, and allopatric populations have evolved differences in morphology and behavior. Here we investigated whether the divergence of pupfish populations in Death Valley might be associated with changes in arginine vasotocin (AVT). We used immunocytochemistry to compare the expression of AVT in the brain of Amargosa pupfish (Cyprinodon nevadensis) from two Death Valley populations: (1) the Amargosa River—a highly variable desert stream containing …

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Variation In Sulfide Tolerance Of Photosystem Ii In Phylogenetically Diverse Cyanobacteria From Sulfidic Habitats, Scott R. Miller, Brad M. Bebout Feb 2004

Variation In Sulfide Tolerance Of Photosystem Ii In Phylogenetically Diverse Cyanobacteria From Sulfidic Habitats, Scott R. Miller, Brad M. Bebout

Biological Sciences Faculty Publications

Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains …

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Ethiopian Soils Harbor Natural Populations Of Rhizobia That Form Symbioses With Common Bean (Phaseolus Vulgaris L.), Serawit Kassa, Desta Beyene, Franklin Ampy, Amha Asseffa, Tadesse Gebremedhin, Peter Van Berkum Feb 2004

Ethiopian Soils Harbor Natural Populations Of Rhizobia That Form Symbioses With Common Bean (Phaseolus Vulgaris L.), Serawit Kassa, Desta Beyene, Franklin Ampy, Amha Asseffa, Tadesse Gebremedhin, Peter Van Berkum

Department of Biology Faculty Publications

The diversity and taxonomic relationships of 83 bean-nodulating rhizobia indigenous to Ethiopian soils were characterized by PCR-RFLP of the internally transcribed spacer (ITS) region between the 16S and 23S rRNA genes, 16S rRNA gene sequence analysis, multilocus enzyme electrophoresis (MLEE), and amplified fragment-length polymorphism. The isolates fell into 13 distinct genotypes according to PCR-RFLP analysis of the ITS region. Based on MLEE, the majority of these genotypes (70%) was genetically related to the type strain of Rhizobium leguminosarum. However, from analysis of their 16S rRNA genes, the majority was placed with Rhizobium etli. Transfer and recombination of the 16S rRNA …

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D1s80 Single-Locus Discrimination Among African Populations, Rene J. Herrera, Leslie R. Adrien, Luis M. Ruiz, Nahir Y. Sanabria, George Duncan Feb 2004

D1s80 Single-Locus Discrimination Among African Populations, Rene J. Herrera, Leslie R. Adrien, Luis M. Ruiz, Nahir Y. Sanabria, George Duncan

Biology Faculty Articles

The highly polymorphic D1S80 locus has no known genetic function. However, this variable number of tandem repeats (VNTR) locus has been highly valuable in forensic identification. In this study we report the allele and genotype frequencies of five African populations (Benin, Cameroon, Egypt, Kenya, and Rwanda), which can be used as databases to help characterize populations and identify individuals. The allele frequencies were used to infer genetic associations through phylogenetic, principal component, and G test statistical analyses. Compliance with Hardy-Weinberg equilibrium expectations was determined as were FST estimates, theta p values, and power of discrimination assessment for each population. …

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A Comparison Between Point- And Semi-Continuous Sampling For Assessing Body Temperature In A Free-Ranging Ectotherm, Emily N. Taylor, Dale F. Denardo, Michael A. Malawy Feb 2004

A Comparison Between Point- And Semi-Continuous Sampling For Assessing Body Temperature In A Free-Ranging Ectotherm, Emily N. Taylor, Dale F. Denardo, Michael A. Malawy

Biological Sciences

We used intracoelomically implanted temperature dataloggers to obtain semi-continuous body temperature data and establish monthly thermal profiles for free-ranging rattlesnakes. We mimicked random and non-random point-sampling methods by selecting a single daily data point from all values or from restricted times of day to reflect common point-sampling constraints. Thermal profiles generated from point-sampling differed from those generated from semi-continuous sampling, and this difference was more apparent when point-sampling was non-random. We conclude that semi-continuous sampling provides a better estimate of thermal profiles, and that point-sampling methods are highly sensitive to deviations from true randomness.

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Maintenance Of Androdioecy In The Freshwater Shrimp, Eulimnadia Texana: Field Estimates Of Inbreeding Depression And Relative Male Survival, Stephen C. Weeks, Richard L. Bernhardt Feb 2004

Maintenance Of Androdioecy In The Freshwater Shrimp, Eulimnadia Texana: Field Estimates Of Inbreeding Depression And Relative Male Survival, Stephen C. Weeks, Richard L. Bernhardt

Biology Faculty Research

Androdioecy is a rare form of reproduction, only found in a few plant and animal species, wherein males co-exist with hermaphrodites. This particular form of mixed mating (mixtures of outcrossing and self-fertilization) is predicted to be evolutionarily unstable, with most androdioecious populations thought to be in a transition from hermaphroditism to dioecy, or vice versa. One well-studied androdioecious species is the freshwater clam shrimp Eulimnadia texana. A model by Otto et al. (1993), exploring the stability of this androdioecious system, predicts that males can co-exist with hermaphrodites when males fertilize an average of over twice the number of offspring that …

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Flagellar Radial Spoke Protein 2 Is A Calmodulin Binding Protein Required For Motility In Chlamydomonas Reinhardtii, Pinfen Yang, Chun Yang, Winfield S. Sale Feb 2004

Flagellar Radial Spoke Protein 2 Is A Calmodulin Binding Protein Required For Motility In Chlamydomonas Reinhardtii, Pinfen Yang, Chun Yang, Winfield S. Sale

Biological Sciences Faculty Research and Publications

Genetic and morphological studies have revealed that the radial spokes regulate ciliary and flagellar bending. Functional and biochemical analysis and the discovery of calmodulin in the radial spokes suggest that the regulatory mechanism involves control of axonemal protein phosphorylation and calcium binding to spoke proteins. To identify potential regulatory proteins in the radial spoke, in-gel kinase assays were performed on isolated axonemes and radial spoke fractions. The results indicated that radial spoke protein 2 (RSP2) can bind ATP and transfer phosphate in vitro. RSP2 was cloned and mapped to the PF24 locus, a gene required for motility. Sequencing revealed that …

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Phylogenetic Signal And The Utility Of 12s And 16s Mtdna In Frog Phylogeny, S. Hertwig, Rafael O. De Sá, A. Haas Feb 2004

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 …

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The Vascular Flora Of The Palo Alto National Battlefield Historic Site, Cameron County, Texas, Robert I. Lonard, Alfred T. Richardson, Norman L. Richard Feb 2004

The Vascular Flora Of The Palo Alto National Battlefield Historic Site, Cameron County, Texas, Robert I. Lonard, Alfred T. Richardson, Norman L. Richard

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

A checklist is provided of the vascular plant taxa of the 1,376 ha Palo Alto Battlefield National Historic Site (PABNHS) in Cameron County of south Texas. PABNHS consists of four plant communities: resacas and tanks, salt flats, brush-grasslands and coastal marshes. Vascular plants of disturbed sites are noted. Two hundred forty-three taxa in 66 families are documented and their community affiliations are given. Three families, Poaceae, Asteraceae and Fabaceae contain 37.5% of the species richness at PABNHS.

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Walking And Running In The Red-Legged Running Frog, Kassina Maculata, Anna N. Ahn, E Furrow, Andrew A. Biewener Jan 2004

Walking And Running In The Red-Legged Running Frog, Kassina Maculata, Anna N. Ahn, E Furrow, Andrew A. Biewener

All HMC Faculty Publications and Research

Although most frog species are specialized for jumping or swimming, Kassina maculata (red-legged running frog) primarily uses a third type of locomotion during which the hindlimbs alternate. In the present study, we examined Kassina's distinct locomotory mode to determine whether these frogs walk or run and how their gait may change with speed. We used multiple methods to distinguish between terrestrial gaits: the existence or absence of an aerial phase, duty factor, relative footfall patterns and the mechanics of the animal's center of mass (COM). To measure kinematic and kinetic variables, we recorded digital video as the animals moved …

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Identifying Character Non-Independence In Phylogenetic Data Using Data Mining Techniques, Jennifer Leopold, Anne M. Maglia, M. Thakur, B. Patel, Fikret ErçAl Jan 2004

Identifying Character Non-Independence In Phylogenetic Data Using Data Mining Techniques, Jennifer Leopold, Anne M. Maglia, M. Thakur, B. Patel, Fikret ErçAl

Computer Science Faculty Research & Creative Works

Undiscovered relationships in a data set may confound analyses, particularly those that assume data independence. Such problems occur when characters used for phylogenetic analyses are not independent of one another. A main assumption of phylogenetic inference methods such as maximum likelihood and parsimony is that each character serves as an independent hypothesis of evolution. When this assumption is violated, the resulting phylogeny may not reflect true evolutionary history. Therefore, it is imperative that character non-independence be identified prior to phylogenetic analyses. To identify dependencies between phylogenetic characters, we applied three data mining techniques: 1) Bayesian networks, 2) decision tree induction, …

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Science On The Rise In Developing Countries, Milena Holmgren, Stefan A. Schnitzer Jan 2004

Science On The Rise In Developing Countries, Milena Holmgren, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

No abstract provided.

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Appendix C: General Data, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2004

Appendix C: General Data, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Togus Pond (2004)

No abstract provided.

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Fall Data Report, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2004

Fall Data Report, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Togus Pond (2004)

No abstract provided.

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Total Phosphorus, Colby College, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2004

Total Phosphorus, Colby College, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Togus Pond (2004)

No abstract provided.

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An Assessment Of Water Quality, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2004

An Assessment Of Water Quality, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: Togus Pond (2004)

No abstract provided.

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Water Quality Results From Togus Pond, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2004

Water Quality Results From Togus Pond, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: Togus Pond (2004)

No abstract provided.

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Forest Fragmentation And The Distribution, Abundance And Conservation Of The Tana River Red Colobus ( Procolobus Rufomitratus), David N.M. Mbora, Douglas B. Meikle Jan 2004

Forest Fragmentation And The Distribution, Abundance And Conservation Of The Tana River Red Colobus ( Procolobus Rufomitratus), David N.M. Mbora, Douglas B. Meikle

Biology

Evidence suggests that habitat heterogeneity, disturbance, disease, predation and food resources influence primate population abundance. However, few studies have focused on what habitat factors determine the probability that a primate species will occur in a habitat fragment. We analysed forest habitat and colobus population attributes to determine factors that influenced occurrence and abundance of the critically endangered Tana River red colobus. The probability of colobus inhabiting forests was positively related to the relative amount of habitat edge and canopy tree species composition. Most of the variance in the density of colobus monkeys was explained by basal area of food trees …

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The Effect Of Loading On Disturbance Sounds Of The Atlantic Croaker Micropogonius Undulatus: Air Versus Water, Michael L. Fine, Justin Schrinel, Timothy M. Cameron Jan 2004

The Effect Of Loading On Disturbance Sounds Of The Atlantic Croaker Micropogonius Undulatus: Air Versus Water, Michael L. Fine, Justin Schrinel, Timothy M. Cameron

Biology Publications

Physiological work on fish sound production may require exposure of the swimbladder to air, which will change its loading (radiation mass and resistance) and could affect parameters of emitted sounds. This issue was examined in Atlantic croaker Micropogonius chromis by recording sounds from the same individuals in air and water. Although sonograms appear relatively similar in both cases, pulse duration is longer because of decreased damping, and sharpness of tuning (Q factor) is higher in water. However, pulse repetition rate and dominant frequency are unaffected. With appropriate caution it is suggested that sounds recorded in air can provide a useful …

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Influence Of The Pacific Decadal Oscillation On Hydrochemistry Of The Rio Grande, Usa, And Mexico, Fasong Yuan, Seiichi Miyamoto Jan 2004

Influence Of The Pacific Decadal Oscillation On Hydrochemistry Of The Rio Grande, Usa, And Mexico, Fasong Yuan, Seiichi Miyamoto

Biological, Geological, and Environmental Faculty Publications

The hydrochemistry has been examined using the major element composition of river water at 12 gauging stations along the Rio Grande. As the Rio Grande Basin consists of two watersheds that have different hydrologic and climatic regimes, two chloride concentration records from the El Paso and Falcon Dam gauging stations have been extracted to reflect long-term variability in river chemistry of the upper and lower basins over the last 50–70 years. Both records contain decadal variability in chloride concentration but are different in nature. The chloride concentration record from the upper basin displays a distinct pattern of decadal variability similar …

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Caenorhabditis Elegans Atx-2 Promotes Germline Proliferation And The Oocyte Fate, Eleanor M. Maine, Dave Hansen, Deborah Springer, Valarie E. Vought Jan 2004

Caenorhabditis Elegans Atx-2 Promotes Germline Proliferation And The Oocyte Fate, Eleanor M. Maine, Dave Hansen, Deborah Springer, Valarie E. Vought

Biology - All Scholarship

In the Caenorhabditis elegans germline, proliferation is induced by Notch-type signaling. Entry of germ cells into meiosis is triggered by activity of the GLD-1 and GLD-2 pathways, which function redundantly to promote meiosis and/or inhibit proliferation. Activation of the germline Notch-type receptor, GLP-1, ultimately inhibits the activities of the GLD-1 and GLD-2 pathways. We previously identified several ego (enhancer of glp-1) genes that promote germline proliferation and interact genetically with the GLP-1 signaling pathway. Here, we show that atx-2 is an ego gene. Our data suggest that ATX-2 is not a positive regulator of the GLP-1 signaling pathway and GLP-1 …

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Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffery W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner Jan 2004

Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffery W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner

Faculty Research & Creative Activity

T.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in south- eastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ? 0.13 female fledglings per year. Of females that re- mained within the study area, 94% fledged young (1.25 ? 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved >10 km) in 2.8 ? 0.6 days; others (36%) …

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