A challenge of life-history theory is to explain why animal body size does not continue to increase, given various advantages of larger size. In birds, body size of nestlings and the number of nestlings produced (brood size) have occasionally been shown to be constrained by higher predation on larger nestlings and those from larger broods. Parasites also are known to have strong effects on life-history traits in birds, but whether parasitism can be a driver...
Data from: Effects of light and topography on regeneration and coexistence of evergreen and deciduous tree species in a Chinese subtropical forestYi Jin, Sabrina E. Russo & Mingjian Yu
1. Evergreen broad-leaved forests are widely distributed in eastern Asia with evergreen (EBL) and deciduous (DBL) broad-leaved tree species coexisting under the same climatic regime, raising questions as to the underlying mechanisms. Since EBL and DBL species differ in leaf lifespan, a key component of resource economic strategies, their coexistence might be attributed to regeneration niche partitioning across habitats varying in resource supply. 2. We investigated the effects of variation in insolation and topography on...
Data from: The roles of ecology, behavior and effective population size in the evolution of a communityChih-Ming Hung, Sergei V. Drovetski & Robert M. Zink
Organismal traits such as ecological specialization and migratory behavior may affect colonization potential, population persistence, and degree of isolation, factors that determine the composition and genetic structure of communities. However, studies focusing on community assembly rarely consider these factors jointly. We sequenced 16 nuclear and one mitochondrial genes from Caucasian and European populations of 30 forest-dwelling avian species that represent diverse ecological (specialist-generalist) and behavioral (migratory-resident) backgrounds. We tested the effects of organismal traits on...
Chemosensory-related gene (CRG) families have been studied extensively in insects, but their evolutionary history across the Arthropoda had remained relatively unexplored. Here, we address current hypotheses and prior conclusions on CRG family evolution using a more comprehensive data set. In particular, odorant receptors were hypothesized to have proliferated during terrestrial colonization by insects (hexapods), but their association with other pancrustacean clades and with independent terrestrial colonizations in other arthropod subphyla have been unclear. We also...
Data from: Climate variability predicts thermal limits of aquatic insects across elevation and latitudeAlisha A. Shah, Brian A. Gill, Andrea C. Encalada, Alexander S. Flecker, W. Chris Funk, Juan M. Guayasamin, Boris C. Kondratieff, N. LeRoy Poff, Steven A. Thomas, Kelly R. Zamudio & Cameron K. Ghalambor
Janzen's extension of the climate variability hypothesis posits that increased seasonal variation at high latitudes should result in greater temperature overlap across elevations, and favor wider thermal breadths in temperate organisms compared to their tropical counterparts. We tested these predictions by measuring stream temperatures and thermal breadths (i.e. the difference between the critical thermal maximum and minimum) of 62 aquatic insect species from temperate (Colorado, USA) and tropical (Papallacta, Ecuador) streams spanning an elevation gradient...
Data from: Females can solve the problem of low signal reliability by assessing multiple male traitsAbigail K. Wegehaupt, Wagner Jr., William E. & William E. Wagner
Male signals that provide information to females about mating benefits are often of low reliability. It is thus not clear why females often express strong signal preferences. We tested the hypothesis that females can distinguish between males with preferred signals that provide lower and higher quality direct benefits. In the field cricket, Gryllus lineaticeps, females usually prefer higher male chirp rates, but chirp rate is positively correlated with the fecundity benefits females will receive from...
Data from: Life history traits and functional processes generate multiple pathways to ecological stabilityJohn P. DeLong, Torrance C. Hanley, Jean P. Gibert, Linda M. Puth & David M. Post
Stability contributes to the persistence of ecological communities, yet the interactions among different stabilizing forces are poorly understood. We assembled mesocosms with an algal resource and 1-8 different clones of the consumer Daphnia ambigua and tracked algal and Daphnia abundances through time. We then fitted coupled ordinary differential equations (ODEs) to the consumer-resource time series. We show that variation in different components of stability (local stability and the magnitude of population fluctuations) across mesocosms arises...
Data from: Rapid evolution rescues hosts from competition and disease but—despite a dilution effect—increases the density of infected hostsAlexander T. Strauss, Jessica L. Hite, Marta S. Shocket, Carla E. Cáceres, Meghan A. Duffy & Spencer R. Hall
Virulent parasites can depress the densities of their hosts. Taxa that reduce disease via dilution effects might alleviate this burden. However, ‘diluter’ taxa can also depress host densities through competition for shared resources. The combination of disease and interspecific competition could even drive hosts extinct. Then again, genetically variable host populations can evolve in response to both competitors and parasites. Can rapid evolution rescue host density from the harm caused by these ecological enemies? How...
Data from: Morphological and molecular evolution and their consequences for conservation and taxonomy in the Le Conte's Thrasher (Toxostoma lecontei)Hernán Vázquez-Miranda, Josie A. Griffin, Jay M. Sheppard, Jordan M. Herman, Octavio Rojas-Soto & Robert M. Zink
We evaluated geographic variation and subspecific taxonomy in the Le Conte's Thrasher (Toxostoma lecontei) by analyzing DNA sequences from 16 nuclear loci, one mitochondrial DNA locus, and four study skin characters, and compared these data sets with previously published data on plumage coloration and different mtDNA genes. Morphological support for the southernmost taxon, T. l. arenicola, is relatively weak: multivariate analyses of morphometrics or back coloration do not provide diagnostic support, although one color character...
Data from: Phytophagous insect oviposition shifts in response to probability of flower abortion owing to the presence of basal fruitsShivani Jadeja & Brigitte Tenhumberg
Phytophagous insects use a wide-range of indicators or associated cues to avoid laying eggs in sites where offspring survival is low. For insects that lay eggs in flowers, these unsuitable sites may be created by the host plant’s resource allocation to flowers. In the sequentially flowering host plant, Yucca glauca, late-opening distal flowers are more likely to be aborted in the presence of already-initiated basal fruits because they are strong resource sinks. If flowers are...
Data from: Cascading effects of changes in land use on the invasion of the walnut Juglans regia in forest ecosystemsMagdalena Lenda, Johannes H. Knops, Piotr Skórka, Dawid Moroń & Michał Woyciechowski
1. Plant invasions are affected by many factors that must be favourable in order for invasions to occur. Factors can be grouped into three major categories: propagule pressure, biotic factors and abiotic characteristics; all may be moderated by human activity. However, studies examining all factors simultaneously are rare, and most are limited to a single factor. This hampers our understanding of the mechanisms driving invasions. 2. In recent decades, an alien walnut (Juglans regia) has...
Nutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations for P, K, and S were evaluated using results from 34 irrigated corn (Zea mays L.) trials conducted in diverse situations across Nebraska. The mean yield was 14.7 Mg ha−1 with adequate fertilizer applied. The median harvest index values were 0.52, 0.89, 0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613...
Data from: Genomic variation across two barn swallow hybrid zones reveals traits associated with divergence in sympatry and allopatryElizabeth S.C. Scordato, Matthew R. Wilkins, Georgy Semenov, Alexander S. Rubtsov, Nolan C. Kane, Rebecca J. Safran & Elizabeth S. C. Scordato
Hybrid zones are geographic regions where isolating barriers between divergent populations are challenged by admixture. Identifying factors that facilitate or inhibit hybridization in sympatry can illuminate the processes that maintain those reproductive barriers. We analyzed patterns of hybridization and phenotypic variation across two newly-discovered hybrid zones between three subspecies of barn swallow (Hirundo rustica). These subspecies differ in ventral coloration and wing length, traits that are targets of sexual and natural selection, respectively, and are...
Hippocampal place field sequences are supported by sensory cues and network internal mechanisms. In contrast, sharp-wave (SPW) sequences, theta sequences, and episode field sequences are internally generated. The relationship of these sequences to memory is unclear. SPW sequences have been shown to support learning and have been assumed to also support episodic memory. Conversely, we demonstrate these SPW sequences were present in trained rats even after episodic memory was impaired and after other internal sequences...
University of Nebraska–Lincoln14
University of Minnesota2
Institute of Systematics and Ecology of Animals1
Howard Hughes Medical Institute1
University of Michigan–Ann Arbor1
Universidad San Francisco de Quito1
University of Wisconsin–Madison1
Florida International University1
Indiana University Bloomington1
University of Maryland, Baltimore County1
University of Colorado Boulder1