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Data from: The evolution of the dicynodont sacrum: constraint and innovation in the synapsid axial column
No full textConstraint is a universal feature of morphological evolution. The vertebral column of synapsids (mammals and their close relatives) is a classic example of this phenotypic restriction, with greatly reduced variation in the number of vertebrae compared to the sauropsid lineage. Synapsids generally possess only three sacral vertebrae, which articulate with the ilium and play a key role in locomotion. Dicynodont anomodonts are the exception to this rule, possessing seven or more sacral vertebrae while reaching a range of body sizes rivaled among synapsids only by therian mammals. Here we explore the evolution of this unusual sacral morphology in dicynodonts by 1) hypothesizing homologies of the additional sacral vertebrae, 2) using ancestral state reconstruction and phylogenetic regressions (e.g., logistic regression, Poisson regression) to track the coevolution of sacral count and body size, and 3) proposing mechanisms by which additional sacral vertebrae were incorporated during dicynodont evolution. We find that sacral vertebra morphology covaries with sacral count in consistent ways across dicynodonts, implying that sacra with a given number of vertebrae are composed of homologous elements. There is a correlation between increased sacral count and larger body size, especially at the shift from four to five sacrals near the origin of Bidentalia. Based on position, morphology, and the consistent number of presacral vertebrae among dicynodonts, we hypothesize that the additional sacrals anterior to the plesiomorphic three are duplications of the first sacral, and that a single caudosacral was incorporated by a shift in the identity of the anteriormost caudal vertebra. Although changes in sacral count appear to be correlated with shifts in body size in dicynodonts, the evolution of general morphological conservativism in the synapsid sacrum remains to be further explored
Data from: Predation selects for smaller eye size in a vertebrate: effects of environmental conditions and sex
No full textIncreased eye size in animals results in a larger retinal image and thus improves visual acuity. Thus, larger eyes should aid both in finding food as well as detecting predators. On the other hand, eyes are usually very conspicuous and several studies have suggested that eye size is associated with predation risk. However, experimental evidence is scanty. In this study, we address how predation affects variation in eye size by performing two experiments using Eurasian perch juveniles as prey and either larger individuals or pike as predators. First, we used large outdoor tanks to compare selection due to predators on relative eye size in open and artificial vegetated habitats. Second, we studied the effects of both predation risk and resource levels on phenotypic plasticity in relative eye size in indoor aquaria experiments. In the first experiment, we found that habitat altered selection due to predators, since predators selected for smaller eye size in a non-vegetated habitat, but not in vegetated habitat. In the plasticity experiment, we found that fish predators induced smaller eye size in males, but not in females, while resource levels had no effect on eye size plasticity. Our experiments provide evidence that predation risk could be one of the driving factors behind variation in eye size within species
duke_turtles
No full textThis is the first subset of images for the paper. Image metadata as well as turtle locations can be found in turtle_image_metadata.csv
Data from: Hierarchical distance sampling to estimate population sizes of common lizards across a desert ecoregion
No full text1) Multi-species wildlife monitoring across large geographical regions is important for effective conservation planning in response to expected impacts from climate change and land use. Unlike many species of birds, mammals, and amphibians which can be efficiently sampled using automated sensors including cameras and sound recorders, reptiles are often much more challenging to detect, in part because of their typically cryptic behavior and generally small body sizes. Although many lizard species are more active during the day which makes them easier to detect using visual encounter surveys, they may be unavailable for sampling during certain periods of the day or year due to their sensitivity to temperature. 2) In recognition of these sampling challenges, we demonstrate application of a recent innovation in distance sampling that adjusts for temporary emigration between repeat survey visits. We used transect surveys to survey lizards at 229 sites throughout the Mojave Desert in California, USA, 2016. 3) We estimated a total population size of 80 million (90% CI: 64–97 million) for the three most common species of lizards across this 66,830 km2 ecoregion. We mapped how density at the 1-km2 scale was predicted to vary with vegetation cover and human development. We validated these results against independent surveys from the southern portion of our study area. 4) Our methods and results demonstrate how multi-species monitoring programs spanning arid ecoregions can better incorporate information about reptiles
Phylogeographic concordance factor analysis
No full textData and scripts for running Phylogeographic Concordance Factors (PCFs) and testing for significance with the analysis
ERC_calculation compressed directory, code and data
No full textCompressed directory contains all code and data to calculate gene-by-gene ERC values for the Drosophila genome. Follow steps and file decriptions in the README.txt file
schmidtetalAEE_dyrad
No full textWeek=week sampled; Gdate=sampling date; fieldcd=site identifier numerical; Field ID=site identifier categorical; Treatment=management at field site; Transect=sampling location at site; veg=vegetation presence between blueberry rows; PropNoncrop=proportion of noncrop habitat in 1km buffer; PropBBtot=proportion of blueberry production in 1km buffer; FRAGEdge=edge density -landscape configuration metric; FRAGSHDI=landscape composition metric; chgNP=change in non-cropping habitat 2016-2017; chgF=change in forest area 2016-2017; SWD=trap counts for Drosophila suzukii; other columns are counts for predator taxa observed in suction sample
Data from: Linking the vectorial capacity of multiple vectors to observed patterns of West Nile virus transmission
No full text1. Theoretical models suggest that increased vector species participation in pathogen transmission significantly increases the prevalence of vector and host infections. However, there has been a lack of empirical evidence to support this.
2. We linked transmission potential of multiple vectors species to observed patterns of enzootic pathogen transmission by conducting longitudinal field surveillance of West Nile virus (WNv) infections in Culex spp. mosquitoes and avian host communities in the southeastern U.S. We then used a temperature-dependent vectorial capacity model as a predictor of WNv infections in mosquitoes and birds using general linear mixed effects models.
3. Two WNv-competent Culex spp. mosquitoes were present in our study sites, Culex restuans Theobald during the spring and Culex quinquefasciatus Say during the summer. Empirical evidence of WNv transmission was limited exclusively to time periods when night time temperatures were suitable for accelerated within-vector viral replication, susceptible avian hosts (i.e. hatch year birds) were abundant, and Culex quinquefasciatus was the primary Culex spp. vector in the mosquito community.
4. Contrary to theoretical predictions, increased presence of competent vector species through time did not significantly increase the prevalence of infections in the WNv enzootic system.
5. Synthesis and applications. We extend a commonly used theoretical framework to quantify transmission potential of vector-borne diseases, the vectorial capacity equation, to account for species-specific variations in temperature-dependent development and host feeding preference. By quantifying key vectorial capacity parameters using field data from southeast United States we quantified the relative contribution of two Culex spp. species (Culex pipiens quinquefasciatus and Culex restuans) to the transmission of West Nile virus (WNv). Our findings suggest that to reduce the risk of human exposure to WNv in urban environments, vector control should focus on the primary WNv vector, the members of the Culex pipiens complex. Additionally, vector control may be more effective if it coincides with the onset of the avian breeding season, when most WNv amplification occurs. Moreover, our results highlight relevant knowledge gaps pertaining to WNv transmission by secondary mosquito species that coexist either in time or space with Culex pipiens complex mosquitoes. A better understanding of secondary WNv vector species is greatly needed in order to appropriately gauge their role in pathogen transmission dynamics