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Full-Text Articles in Life Sciences

Fire Induced Reproductive Mechanisms Of A Symphoricarpos (Caprifoliaceae) Shrub After Dormant Season Burning, John Derek Scasta, David M. Engle, Ryan N. Harr, Diane M. Debinski Dec 2014

Fire Induced Reproductive Mechanisms Of A Symphoricarpos (Caprifoliaceae) Shrub After Dormant Season Burning, John Derek Scasta, David M. Engle, Ryan N. Harr, Diane M. Debinski

Ecology, Evolution and Organismal Biology Publications

Background: Symphoricarpos, a genus of the Caprifoliaceae family, consists of about 15 species of clonal deciduous shrubs in North America and 1 species endemic to China. In North American tallgrass prairie, Symphoricarpos orbiculatus (buckbrush) is the dominant shrub often forming large colonies via sexual and asexual reproductive mechanisms. Symphoricarpos shrubs, in particular S. orbiculatus, use a unique sexual reproductive mechanism known as layering where vertical stems droop and the tips root upon contact with the soil. Because of conflicting societal values of S. orbiculatus for conservation and agriculture and the current attempt to restore historical fire regimes, there is a ...


Cenh3 Evolution In Diploids And Polyploids Of Three Angiosperm Genera, Rick E. Masonbrink, Joseph P. Gallagher, Josef J. Jareczek, Simon Renny-Byfield, Corrinne E. Grover, Lei Gong, Jonathan F. Wendel Dec 2014

Cenh3 Evolution In Diploids And Polyploids Of Three Angiosperm Genera, Rick E. Masonbrink, Joseph P. Gallagher, Josef J. Jareczek, Simon Renny-Byfield, Corrinne E. Grover, Lei Gong, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Centromeric DNA sequences alone are neither necessary nor sufficient for centromere specification. The centromere specific histone, CenH3, evolves rapidly in many species, perhaps as a coevolutionary response to rapidly evolving centromeric DNA. To gain insight into CenH3 evolution, we characterized patterns of nucleotide and protein diversity among diploids and allopolyploids within three diverse angiosperm genera, Brassica, Oryza, and Gossypium (cotton), with a focus on evidence for diversifying selection in the various domains of the CenH3 gene. In addition, we compare expression profiles and alternative splicing patterns for CenH3 in representatives of each genus. All three genera retain both duplicated CenH3 ...


Control Of Cotton Fibre Elongation By A Homeodomain Transcription Factor Ghhox3, Chun-Min Shan, Ziao-Xia Shangguan, Bo Zhao, Xiu-Fang Zhang, Lu-Men Chao, Chang-Qing Yang, Ling-Jian Wang, Hua-Yu Zhu, Yan-Da Zeng, Wang-Zhen Guo, Bao-Liang Zhou, Guanjing Hu, Xue-Ying Guan, Z. Jeffrey Chen, Jonathan F. Wendel, Tian-Zhen Zhang, Xiao-Ya Chen Nov 2014

Control Of Cotton Fibre Elongation By A Homeodomain Transcription Factor Ghhox3, Chun-Min Shan, Ziao-Xia Shangguan, Bo Zhao, Xiu-Fang Zhang, Lu-Men Chao, Chang-Qing Yang, Ling-Jian Wang, Hua-Yu Zhu, Yan-Da Zeng, Wang-Zhen Guo, Bao-Liang Zhou, Guanjing Hu, Xue-Ying Guan, Z. Jeffrey Chen, Jonathan F. Wendel, Tian-Zhen Zhang, Xiao-Ya Chen

Ecology, Evolution and Organismal Biology Publications

Cotton fibres are unusually long, single-celled epidermal seed trichomes and a model for plant cell growth, but little is known about the regulation of fibre cell elongation. Here we report that a homeodomain-leucine zipper (HD-ZIP) transcription factor, GhHOX3, controls cotton fibre elongation. GhHOX3 genes are localized to the 12th homoeologous chromosome set of allotetraploid cotton cultivars, associated with quantitative trait loci (QTLs) for fibre length. Silencing of GhHOX3 greatly reduces (>80%) fibre length, whereas its overexpression leads to longer fibre. Combined transcriptomic and biochemical analyses identify target genes of GhHOX3 that also contain the L1-box cis-element, including two cell ...


Demonstrating Microbial Co-Occurrence Pattern Analyses Within And Between Ecosystems, Ryan J. Williams, Adina C. Howe, Kirsten S. Hofmockel Jul 2014

Demonstrating Microbial Co-Occurrence Pattern Analyses Within And Between Ecosystems, Ryan J. Williams, Adina C. Howe, Kirsten S. Hofmockel

Ecology, Evolution and Organismal Biology Publications

Co-occurrence patterns are used in ecology to explore interactions between organisms and environmental effects on coexistence within biological communities. Analysis of co-occurrence patterns among microbial communities has ranged from simple pairwise comparisons between all community members to direct hypothesis testing between focal species. However, co-occurrence patterns are rarely studied across multiple ecosystems or multiple scales of biological organization within the same study. Here we outline an approach to produce co-occurrence analyses that are focused at three different scales: co-occurrence patterns between ecosystems at the community scale, modules of co-occurring microorganisms within communities, and co-occurring pairs within modules that are nested ...


Aboveground Tree Growth Varies With Belowground Carbon Allocation In A Tropical Rainforest Environment, James W. Raich, Deborah A. Clark, Litgard Schwendenmann, Tana E. Wood Jun 2014

Aboveground Tree Growth Varies With Belowground Carbon Allocation In A Tropical Rainforest Environment, James W. Raich, Deborah A. Clark, Litgard Schwendenmann, Tana E. Wood

Ecology, Evolution and Organismal Biology Publications

Young secondary forests and plantations in the moist tropics often have rapid rates of biomass accumulation and thus sequester large amounts of carbon. Here, we compare results from mature forest and nearby 15–20 year old tree plantations in lowland Costa Rica to evaluate differences in allocation of carbon to aboveground production and root systems. We found that the tree plantations, which had fully developed, closed canopies, allocated more carbon belowground - to their root systems - than did mature forest. This increase in belowground carbon allocation correlated significantly with aboveground tree growth but not with canopy production (i.e., leaf fall ...


Widespread Rapid Reductions In Body Size Of Adult Salamanders In Response To Climate Change, Nicholas M. Caruso, Michael W. Sears, Dean C. Adams, Karen R. Lips Jun 2014

Widespread Rapid Reductions In Body Size Of Adult Salamanders In Response To Climate Change, Nicholas M. Caruso, Michael W. Sears, Dean C. Adams, Karen R. Lips

Ecology, Evolution and Organismal Biology Publications

Reduction in body size is a major response to climate change, yet evidence in globally imperiled amphibians is lacking. Shifts in average population body size could indicate either plasticity in the growth response to changing climates through changes in allocation and energetics, or through selection for decreased size where energy is limiting. We compared historic and contemporary size measurements in 15 Plethodon species from 102 populations (9450 individuals) and found that six species exhibited significant reductions in body size over 55 years. Biophysical models, accounting for actual changes in moisture and air temperature over that period, showed a 7.1 ...


Ancient Gene Duplicates In Gossypium (Cotton) Exhibit Near-Complete Expression Divergence, Simon Renny-Byfield, Joseph P. Gallagher, Corrinne E. Grover, Emmanuel Szadkowski, Justin T. Page, Joshua A. Udall, Xiyin Wang, Andrew H. Paterson, Jonathan F. Wendel Apr 2014

Ancient Gene Duplicates In Gossypium (Cotton) Exhibit Near-Complete Expression Divergence, Simon Renny-Byfield, Joseph P. Gallagher, Corrinne E. Grover, Emmanuel Szadkowski, Justin T. Page, Joshua A. Udall, Xiyin Wang, Andrew H. Paterson, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Whole genome duplication (WGD) is widespread in flowering plants and is a driving force in angiosperm diversification. The redundancy introduced by WGD allows the evolution of novel gene interactions and functions, although the patterns and processes of diversification are poorly understood. We identified ∼ 2,000 pairs of paralogous genes in Gossypium raimondii (cotton) resulting from an approximately 60 My old 5- to 6-fold ploidy increase. Gene expression analyses revealed that, in G. raimondii, 99.4% of the gene pairs exhibit differential expression in at least one of the three tissues (petal, leaf, and seed), with 93% to 94% exhibiting differential ...


Assessing Trait Covariation And Morphological Integration On Phylogenies Using Evolutionary Covariance Matrices, Dean C. Adams, Ryan N. Felice Apr 2014

Assessing Trait Covariation And Morphological Integration On Phylogenies Using Evolutionary Covariance Matrices, Dean C. Adams, Ryan N. Felice

Ecology, Evolution and Organismal Biology Publications

Morphological integration describes the degree to which sets of organismal traits covary with one another. Morphological covariation may be evaluated at various levels of biological organization, but when characterizing such patterns across species at the macroevolutionary level, phylogeny must be taken into account. We outline an analytical procedure based on the evolutionary covariance matrix that allows species-level patterns of morphological integration among structures defined by sets of traits to be evaluated while accounting for the phylogenetic relationships among taxa, providing a flexible and robust complement to related phylogenetic independent contrasts based approaches. Using computer simulations under a Brownian motion model ...


Trade-Offs And Coexistence: A Lottery Model Applied To Fig Wasp Communities, A. Bradley Duthie, Karen C. Abbott, John D. Nason Apr 2014

Trade-Offs And Coexistence: A Lottery Model Applied To Fig Wasp Communities, A. Bradley Duthie, Karen C. Abbott, John D. Nason

Ecology, Evolution and Organismal Biology Publications

Ecological communities in which organisms complete their life cycles on discrete ephemeral patches are common and often support an unusually large number of species. Explaining this diversity is challenging for communities of ecologically similar species undergoing preemptive competition, where classic coexistence mechanisms may not readily apply. We use nonpollinating fig wasps as a model community characterized by high diversity and preemptive competition to show how subadditive population growth and a tradeoff between competitor fecundity and dispersal ability can lead to coexistence. Because nonpollinator species are often closely related, have similar life histories, and compete for the same discrete resources, understanding ...


Predator Perception Of Batesian Mimicry And Conspicuousness In A Salamander, Andrew C. Kraemer, Dean C. Adams Apr 2014

Predator Perception Of Batesian Mimicry And Conspicuousness In A Salamander, Andrew C. Kraemer, Dean C. Adams

Ecology, Evolution and Organismal Biology Publications

In Batesian mimicry a palatable mimic deceives predators by resembling an unpalatable model. The evolution of Batesian mimicry relies on the visual capabilities of the potential predators, as prey detection provides the selective force driving evolutionary change. We compared the visual capabilities of several potential predators to test predictions stemming from the hypothesis of Batesian mimicry between two salamanders: the model species Notophthalmus viridescens, and polymorphic mimic, Plethodon cinereus. First, we found mimicry to be restricted to coloration, but not brightness. Second, only bird predators appeared able to discriminate between the colors of models and non-mimic P. cinereus. Third, estimates ...


Lethal Interactions Between Parasites And Prey Increase Niche Diversity In A Tropical Community, Marty A. Condon, Sonja J. Scheffer, Matthew L. Lewis, Robert Wharton, Dean C. Adams, Andrew A. Forbes Mar 2014

Lethal Interactions Between Parasites And Prey Increase Niche Diversity In A Tropical Community, Marty A. Condon, Sonja J. Scheffer, Matthew L. Lewis, Robert Wharton, Dean C. Adams, Andrew A. Forbes

Ecology, Evolution and Organismal Biology Publications

Ecological specialization should minimize niche overlap, yet herbivorous neotropical flies (Blepharoneura) and their lethal parasitic wasps (parasitoids) exhibit both extreme specialization and apparent niche overlap in host plants. From just two plant species at one site in Peru, we collected 3636 flowers yielding 1478 fly pupae representing 14 Blepharoneura fly species, 18 parasitoid species (14 Bellopius species), and parasitoid-host associations, all discovered through analysis of molecular data. Multiple sympatric species specialize on the same sex flowers of the same fly host-plant species—which suggests extreme niche overlap; however, niche partitioning was exposed by interactions between wasps and flies. Most Bellopius ...


Swimming Against The Tide: Resilience Of A Riverine Turtle To Recurrent Extreme Environmental Events, Abigail M. Jergenson, David A. W. Miller, Lorin A. Neuman-Lee, Daniel A. Warner, Fredric J. Janzen Mar 2014

Swimming Against The Tide: Resilience Of A Riverine Turtle To Recurrent Extreme Environmental Events, Abigail M. Jergenson, David A. W. Miller, Lorin A. Neuman-Lee, Daniel A. Warner, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Extreme environmental events (EEEs) are likely to exert deleterious effects on populations. From 1996 to 2012 we studied the nesting dynamics of a riverine population of painted turtles (Chrysemys picta) that experienced seven years with significantly definable spring floods. We used capture–mark–recapture methods to estimate the relationships between more than 5 m and more than 6 m flood events and population parameters. Contrary to expectations, flooding was not associated with annual differences in survival, recruitment or annual population growth rates of the adult female segment of the population. These findings suggest that female C. pictaexhibit resiliency to ...


Population Genetics Of Blanding’S Turtle (Emys Blandingii) In The Midwestern United States, Arun Sethuraman, Suzanne E. Mcgaugh, Morgan L. Becker, Christopher H. Chandler, James L. Christiansen, Sue Hayden, Andrea Leclere, Jennifer Monson-Miller, Erin M. Myers, Ryan T. Paitz, Jeanine M. Refsnider, Terry J. Vandewalle, Fredric J. Janzen Feb 2014

Population Genetics Of Blanding’S Turtle (Emys Blandingii) In The Midwestern United States, Arun Sethuraman, Suzanne E. Mcgaugh, Morgan L. Becker, Christopher H. Chandler, James L. Christiansen, Sue Hayden, Andrea Leclere, Jennifer Monson-Miller, Erin M. Myers, Ryan T. Paitz, Jeanine M. Refsnider, Terry J. Vandewalle, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Blanding’s turtle (Emys blandingii) has declined substantially in North America due to anthropogenic activities, leaving populations smaller and increasingly fragmented spatially. We sampled 212 turtles to evaluate variation at eight microsatellite loci within and among 18 populations of E. blandingii across its primary range in the midwestern United States (Illinois, Iowa, Minnesota, and Nebraska). All loci and populations were highly polymorphic. Our analyses also detected considerable genetic structure within and among the sampled localities, and revealed ancestral gene flow of E. blandingii in this region north and east from an ancient refugium in the central Great Plains, concordant with ...


Connecting Soil Organic Carbon And Root Biomass With Land-Use And Vegetation In Temperate Grassland, Devan Allen Mcgranahan, Aaron Lee Daigh, Jessica J. Veenstra, David M. Engle, James R. Miller, Diane M. Debinski Jan 2014

Connecting Soil Organic Carbon And Root Biomass With Land-Use And Vegetation In Temperate Grassland, Devan Allen Mcgranahan, Aaron Lee Daigh, Jessica J. Veenstra, David M. Engle, James R. Miller, Diane M. Debinski

Ecology, Evolution and Organismal Biology Publications

Soils containmuch of Earth’s terrestrial organic carbon but are sensitive to land-use. Rangelands are important to carbon dynamics and are among ecosystems most widely impacted by land-use. While common practices like grazing, fire, and tillage affect soil properties directly related to soil carbon dynamics, their magnitude and direction of change vary among ecosystems and with intensity of disturbance. We describe variability in soil organic carbon (SOC) and root biomass—sampled from 0–170 cm and 0– 100 cm, respectively—in terms of soil properties, land-use history, current management, and plant community composition using linear regression and multivariate ordination. Despite ...


Lymantria Dispar Iflavirus 1 (Ldiv1), A New Model To Study Iflaviral Persistence In Lepidopterans, Jimena Carrillo-Tripp, Elizabeth N. Krueger, Robert L. Harrison, Amy L. Toth, W. Allen Miller, Bryony C. Bonning Jan 2014

Lymantria Dispar Iflavirus 1 (Ldiv1), A New Model To Study Iflaviral Persistence In Lepidopterans, Jimena Carrillo-Tripp, Elizabeth N. Krueger, Robert L. Harrison, Amy L. Toth, W. Allen Miller, Bryony C. Bonning

Ecology, Evolution and Organismal Biology Publications

The cell line IPLB-LD-652Y, derived from the gypsy moth (Lymantria dispar L.), is routinely used to study interactions between viruses and insect hosts. Here we report the full genome sequence and biological characteristics of a small RNA virus, designated Lymantria dispar iflavirus 1 (LdIV1), that was discovered to persistently infect IPLB-LD-652Y. LdIV1 belongs to the genus Iflavirus. LdIV1 formed icosahedral particles of approx. 30 nm in diameter and contained a 10 044 nt polyadenylated, positive-sense RNA genome encoding a predicted polyprotein of 2980 aa. LdIV1 was induced by a viral suppressor of RNA silencing, suggesting that acute infection is restricted ...


Biodemography Of Ectothermic Tetrapods Provides Insights Into The Evolution And Plasticity Of Mortality Patterns, David A. W. Miller, Fredric Janzen, Gary M. Fellers, Patrick M. Kleeman, Anne M. Bronikowski Jan 2014

Biodemography Of Ectothermic Tetrapods Provides Insights Into The Evolution And Plasticity Of Mortality Patterns, David A. W. Miller, Fredric Janzen, Gary M. Fellers, Patrick M. Kleeman, Anne M. Bronikowski

Ecology, Evolution and Organismal Biology Publications

Evolution acts to shape aging rates within the set of ecological and organismal constraints that individual species experience. Biodemography seeks to understand the shape of age-dependent reproductive and mortality patterns and how they are impacted by these constraints (Carey and Vaupel, 2006). Although model laboratory organisms have been crucial to understanding patterns and causes of aging, there is great value in also studying the underlying evolutionary and ecological forces that shape rates of aging in the environment in which they evolved. In this paper we examine the biodemography of wild populations of three species (a turtle, a frog, and a ...


Impacts Of Climate Change Drivers On C4 Grassland Productivity: Scaling Driver Effects Through The Plant Community, H. Wayne Polley, Justin D. Derner, Robert B. Jackson, Brian J. Wilsey, Philip A. Fay Jan 2014

Impacts Of Climate Change Drivers On C4 Grassland Productivity: Scaling Driver Effects Through The Plant Community, H. Wayne Polley, Justin D. Derner, Robert B. Jackson, Brian J. Wilsey, Philip A. Fay

Ecology, Evolution and Organismal Biology Publications

Climate change drivers affect plant community productivity via three pathways: (i) direct effects of drivers on plants; (ii) the response of species abundances to drivers (community response); and (iii) the feedback effect of community change on productivity (community effect). The contribution of each pathway to driver–productivity relationships depends on functional traits of dominant species. We used data from three experiments in Texas, USA, to assess the role of community dynamics in the aboveground net primary productivity (ANPP) response of C4 grasslands to two climate drivers applied singly: atmospheric CO2 enrichment and augmented summer precipitation. The ANPPdriver response differed among ...


Tree Of Sex: A Database Of Sexual Systems, Tia-Lynn Ashman, Doris Bachtrog, Heath Blackmon, Emma E. Goldberg, Matthew W. Hahn, Mark Kirkpatrick, Jun Kitano, Judith E. Mank, Itay Mayrose, Ray Ming, Sarah P. Otto, Catherine L. Peichel, Matthew W. Pennell, Nicolas Perrin, Laura Ross, Nicole M. Valenzuela, Jana C. Vamosi Jan 2014

Tree Of Sex: A Database Of Sexual Systems, Tia-Lynn Ashman, Doris Bachtrog, Heath Blackmon, Emma E. Goldberg, Matthew W. Hahn, Mark Kirkpatrick, Jun Kitano, Judith E. Mank, Itay Mayrose, Ray Ming, Sarah P. Otto, Catherine L. Peichel, Matthew W. Pennell, Nicolas Perrin, Laura Ross, Nicole M. Valenzuela, Jana C. Vamosi

Ecology, Evolution and Organismal Biology Publications

The vast majority of eukaryotic organisms reproduce sexually, yet the nature of the sexual system and the mechanism of sex determination often vary remarkably, even among closely related species. Some species of animals and plants change sex across their lifespan, some contain hermaphrodites as well as males and females, some determine sex with highly differentiated chromosomes, while others determine sex according to their environment. Testing evolutionary hypotheses regarding the causes and consequences of this diversity requires interspecific data placed in a phylogenetic context. Such comparative studies have been hampered by the lack of accessible data listing sexual systems and sex ...


Comparative Evolutionary And Developmental Dynamics Of The Cotton (Gossypium Hirsutum) Fiber Transcriptome, Mi-Jeong Yoo, Jonathan F. Wendel Jan 2014

Comparative Evolutionary And Developmental Dynamics Of The Cotton (Gossypium Hirsutum) Fiber Transcriptome, Mi-Jeong Yoo, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

The single-celled cotton (Gossypium hirsutum) fiber provides an excellent model to investigate how human selection affects phenotypic evolution. To gain insight into the evolutionary genomics of cotton domestication, we conducted comparative transcriptome profiling of developing cotton fibers using RNA-Seq. Analysis of single-celled fiber transcriptomes from four wild and five domesticated accessions from two developmental time points revealed that at least one-third and likely onehalf of the genes in the genome are expressed at any one stage during cotton fiber development. Among these, ,5,000 genes are differentially expressed during primary and secondary cell wall synthesis between wild and domesticated cottons ...


Shared Genes Related To Aggression, Rather Than Chemical Communication, Are Associated With Reproductive Dominance In Paper Wasps (Polistes Metricus), Amy L. Toth, John F. Tooker, Srihari Radhakrishnan, Robert Minard, Michael T. Henshaw, Christina M. Grozinger Jan 2014

Shared Genes Related To Aggression, Rather Than Chemical Communication, Are Associated With Reproductive Dominance In Paper Wasps (Polistes Metricus), Amy L. Toth, John F. Tooker, Srihari Radhakrishnan, Robert Minard, Michael T. Henshaw, Christina M. Grozinger

Ecology, Evolution and Organismal Biology Publications

Background
In social groups, dominant individuals may socially inhibit reproduction of subordinates using aggressive interactions or, in the case of highly eusocial insects, pheromonal communication. It has been hypothesized these two modes of reproductive inhibition utilize conserved pathways. Here, we use a comparative framework to investigate the chemical and genomic underpinnings of reproductive dominance in the primitively eusocial wasp Polistes metricus. Our goals were to first characterize transcriptomic and chemical correlates of reproductive dominance and second, to test whether dominance-associated mechanisms in paper wasps overlapped with aggression or pheromone-related gene expression patterns in other species. To explore whether conserved molecular ...


Exogenous Application Of Estradiol To Eggs Unexpectedly Induces Male Development In Two Turtle Species With Temperaturedependent Sex Determination, Daniel A. Warner, Elizabeth Addis, Wei-Guo Du, Thane Wibbels, Fredric J. Janzen Jan 2014

Exogenous Application Of Estradiol To Eggs Unexpectedly Induces Male Development In Two Turtle Species With Temperaturedependent Sex Determination, Daniel A. Warner, Elizabeth Addis, Wei-Guo Du, Thane Wibbels, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Steroid hormones affect sex determination in a variety of vertebrates. The feminizing effects of exposure to estradiol and the masculinizing effects of aromatase inhibition during development are well established in a broad range of vertebrate taxa, but paradoxical findings are occasionally reported. Four independent experiments were conducted on two turtle species with temperature-dependent sex determination (Chrysemys picta and Chelydra serpentina) to quantify the effects of egg incubation temperature, estradiol, and an aromatase inhibitor on offspring sex ratios. As expected, the warmer incubation temperatures induced female development and the cooler temperatures produced primarily males. However, application of an aromatase inhibitor had ...


Immobile And Mobile Life-History Stages Have Different Thermal Physiologies In A Lizard, Rory S. Telemeco Jan 2014

Immobile And Mobile Life-History Stages Have Different Thermal Physiologies In A Lizard, Rory S. Telemeco

Ecology, Evolution and Organismal Biology Publications

Temperature affects multiple aspects of an organism’s biology and thus defines a major axis of the fundamental niche. For ectotherms, variation in the thermal environment is particularly important because most of these taxa have a limited capacity to thermoregulate via metabolic heat production. While temperature affects all life-history stages, stages can differ in their ability to respond to the thermal environment. For example, in oviparous organisms, free-living adults can behaviorally thermoregulate, whereas developing embryos are at the mercy of the nest environment. These differences in the realized thermal environment should select for life-history stages to have different thermal tolerances ...


Trans-Gulf Of Mexico Loop Migration Of Tree Swallows Revealed By Solar Geolocation, David W. Bradley, Robert G. Clark, Peter O. Dunn, Andrew J. Laughlin, Caz M. Taylor, Carol M. Vleck, Linda A. Whittingham, David W. Winkler, D. Ryan Norris Jan 2014

Trans-Gulf Of Mexico Loop Migration Of Tree Swallows Revealed By Solar Geolocation, David W. Bradley, Robert G. Clark, Peter O. Dunn, Andrew J. Laughlin, Caz M. Taylor, Carol M. Vleck, Linda A. Whittingham, David W. Winkler, D. Ryan Norris

Ecology, Evolution and Organismal Biology Publications

One of the greatest feats of avian migration is the non-stop crossing of extensive areas of inhospitable habitat such as deserts and seas. Differences in spring and autumn migration routes have been reported in species that cross such barriers, and are thought to have evolved in response to seasonal variation in prevailing wind direction. We tested the hypothesis that migration routes vary seasonally with respect to the Gulf of Mexico in the tree swallow Tachycineta bicolor using solar geolocators attached and retrieved at 4 breeding sites in central North America. We found that 100 % of birds (n = 10) made a ...


Invaded Grassland Communities Have Altered Stability-Maintenance Mechanisms But Equal Stability Compared To Native Communities, Brian J. Wilsey, Pedram P. Daneshgar, Kirsten S. Hofmockel, H. Wayne Polley Jan 2014

Invaded Grassland Communities Have Altered Stability-Maintenance Mechanisms But Equal Stability Compared To Native Communities, Brian J. Wilsey, Pedram P. Daneshgar, Kirsten S. Hofmockel, H. Wayne Polley

Ecology, Evolution and Organismal Biology Publications

Theory predicts that stability should increase with diversity via several mechanisms. We tested predictions in a 5-year experiment that compared low-diversity exotic to high-diversity native plant mixtures under two irrigation treatments. The study included both wet and dry years. Variation in biomass across years (CV) was 50% lower in mixtures than monocultures of both native and exotic species. Growth among species was more asynchronous and overyielding values were greater during and after a drought in native than exotic mixtures. Mean-variance slopes indicated strong portfolio effects in both community types, but the intercept was higher for exotics than for natives, suggesting ...


Herbivores And Nutrients Control Grassland Plant Diversity Via Light Limitation, Elizabeth T. Borer, Eric W. Seabloom, Daniel S. Gruner, W. Stanley Harpole, Helmut Hillebrand, Eric M. Lind, Peter B. Adler, Juan Alberti, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Dana Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Yvonne M. Buckley, Marc Cadotte, Chengjin Chu, Elsa E. Cleland, Michael J. Crawley, Pedro Daleo, Ellen I. Damschen, Kendi F. Davies, Nicole M. Decrappeo, Guozhen Du, Jennifer Firn, Yann Hautier, Robert W. Heckman, Andy Hector, Janneke Hillerislambers, Oscar Iribarne, Julia A. Klein, Johannes M. H. Knops, Kimberly J. La Pierre, Andrew D. B. Leakey, Wei Li, Andrew S. Macdougall, Rebecca L. Mcculley, Brett A. Melbourne, Charles E. Mitchell, Joslin L. Moore, Brent D. Mortensen, Lydia R. O'Halloran, John L. Orrock, Jesus Pascual, Suzanne M. Prober, David A. Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly J. Stevens, Lauren K. Sullivan, Ryan J. Williams, Peter D. Wragg, Justin P. Wright, Louie H. Yang Jan 2014

Herbivores And Nutrients Control Grassland Plant Diversity Via Light Limitation, Elizabeth T. Borer, Eric W. Seabloom, Daniel S. Gruner, W. Stanley Harpole, Helmut Hillebrand, Eric M. Lind, Peter B. Adler, Juan Alberti, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Dana Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Yvonne M. Buckley, Marc Cadotte, Chengjin Chu, Elsa E. Cleland, Michael J. Crawley, Pedro Daleo, Ellen I. Damschen, Kendi F. Davies, Nicole M. Decrappeo, Guozhen Du, Jennifer Firn, Yann Hautier, Robert W. Heckman, Andy Hector, Janneke Hillerislambers, Oscar Iribarne, Julia A. Klein, Johannes M. H. Knops, Kimberly J. La Pierre, Andrew D. B. Leakey, Wei Li, Andrew S. Macdougall, Rebecca L. Mcculley, Brett A. Melbourne, Charles E. Mitchell, Joslin L. Moore, Brent D. Mortensen, Lydia R. O'Halloran, John L. Orrock, Jesus Pascual, Suzanne M. Prober, David A. Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly J. Stevens, Lauren K. Sullivan, Ryan J. Williams, Peter D. Wragg, Justin P. Wright, Louie H. Yang

Ecology, Evolution and Organismal Biology Publications

Human alterations to nutrient cycles1, 2 and herbivore communities3, 4, 5, 6, 7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8, 9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates ...


Cytonuclear Evolution Of Rubisco In Four Allopolyploid Lineages, Lei Gong, Mischa Olson, Jonathan F. Wendel Jan 2014

Cytonuclear Evolution Of Rubisco In Four Allopolyploid Lineages, Lei Gong, Mischa Olson, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Allopolyploidization in plants entails the merger of two divergent nuclear genomes, typically with only one set (usually maternal) of parental plastidial and mitochondrial genomes and with an altered cytonuclear stoichiometry. Thus, we might expect cytonuclear coevolution to be an important dimension of allopolyploid evolution. Here, we investigate cytonuclear coordination for the key chloroplast protein rubisco (ribulose 1,5-bisphosphate carboxylase/oxygenase), which is composed of nuclear-encoded, small subunits (SSUs) and plastid-encoded, large subunits. By studying gene composition and diversity as well as gene expression in four model allopolyploid lineages, Arabidopsis, Arachis, Brassica, and Nicotiana, we demonstrate that paralogous nuclear-encoded rbcS genes ...


Landowners' Perceptions Of Risk In Grassland Management: Woody Plant Encroachment And Prescribed Fire, Ryan N. Harr, Lois Wright Morton, Shannon R. Rusk, David M. Engle, James R. Miller, Diane M. Debinski Jan 2014

Landowners' Perceptions Of Risk In Grassland Management: Woody Plant Encroachment And Prescribed Fire, Ryan N. Harr, Lois Wright Morton, Shannon R. Rusk, David M. Engle, James R. Miller, Diane M. Debinski

Ecology, Evolution and Organismal Biology Publications

Ecologists recognize that fire and herbivory are essential to maintaining habitat quality in grassland ecosystems. Prescribed fire and grazing are typically used on public reserves to increase biodiversity, improve grassland productivity, and control encroachment of woody plants. However, these tools, particularly prescribed fire, have not been widely adopted by private landowners. Fire suppression and prescribed fire are strategies that present competing risks to owners who make management decisions. We explore landowner perceptions of risk associated with (1) eastern redcedar (Juniperus virginiana) encroachment, and (2) the use of prescribed fire to control woody species in the Grand River Grasslands of Iowa ...


Sex Determination: Why So Many Ways Of Doing It?, Doris Bachtrog, Judith E. Mank, Catherine L. Peichel, Mark Kirkpatrick, Sarah P. Otto, Tia-Lynn Ashman, Matthew W. Hahn, Jun Kitano, Itay Mayrose, Ray Ming, Nicolas Perrin, Laura Ross, Nicole M. Valenzuela, Jana C. Vamosi Jan 2014

Sex Determination: Why So Many Ways Of Doing It?, Doris Bachtrog, Judith E. Mank, Catherine L. Peichel, Mark Kirkpatrick, Sarah P. Otto, Tia-Lynn Ashman, Matthew W. Hahn, Jun Kitano, Itay Mayrose, Ray Ming, Nicolas Perrin, Laura Ross, Nicole M. Valenzuela, Jana C. Vamosi

Ecology, Evolution and Organismal Biology Publications

Sexual reproduction is an ancient feature of life on earth, and the familiar X and Y chromosomes in humans and other model species have led to the impression that sex determination mechanisms are old and conserved. In fact, males and females are determined by diverse mechanisms that evolve rapidly in many taxa. Yet this diversity in primary sex-determining signals is coupled with conserved molecular pathways that trigger male or female development. Conflicting selection on different parts of the genome and on the two sexes may drive many of these transitions, but few systems with rapid turnover of sex determination mechanisms ...


At The Brink Of Eusociality: Transcriptomic Correlates Of Worker Behaviour In A Small Carpenter Bee, Sandra Rehan, Ali J. Berens, Amy L. Toth Jan 2014

At The Brink Of Eusociality: Transcriptomic Correlates Of Worker Behaviour In A Small Carpenter Bee, Sandra Rehan, Ali J. Berens, Amy L. Toth

Ecology, Evolution and Organismal Biology Publications

Background: There is great interest in understanding the genomic underpinnings of social evolution, in particular, the evolution of eusociality (caste-containing societies with non-reproductives that care for siblings). Subsociality is a key precursor for the evolution of eusociality and characterized by prolonged parental care and parent-offspring interaction. Here, we provide the first transcriptomic data for the small carpenter bee, Ceratina calcarata. This species is of special interest because it is subsocial and in the same family as the highly eusocial honey bee, Apis mellifera. In addition, some C. calcarata females demonstrate alloparental care without reproduction, which provides a unique opportunity to ...