Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
1,956
datasets available to search
ShareScore release 0.9.0
Dataset results
1,956 results for “test data”
Data from: Exaggerated sexual swellings and male mate choice in primates: testing the reliable indicator hypothesis in the Amboseli baboons
The paradigm of competitive males vying to influence female mate choice has been repeatedly upheld, but, increasingly, studies also report competitive females and choosy males. One female trait that is commonly proposed to influence male mate choice is the exaggerated sexual swelling displayed by females of many Old World primate species. The reliable indicator hypothesis posits that females use the exaggerated swellings to compete for access to mates, and that the swellings advertise variation in female fitness. We tested the two main predictions of this hypothesis in a wild population of baboons (Papio cynocephalus). First, we examined the effect of swelling size on the probability of mate guarding ('consortship') by the highest-ranking male and the behaviour of those males that trailed consortships ('follower males'). Second, we asked whether a female's swelling size predicted several fitness measures. We found that high-ranking males did not prefer females with larger swellings (when controlling for cycle number and conception) and that females with larger swellings did not have higher reproductive success. Our study, the only complete test of the reliable indicator hypothesis in a primate population, rejects the idea that female baboons compete for mates by advertising heritable fitness differences. Furthermore, we found unambiguous evidence that males biased their mating decisions in favour of females who had experienced more sexual cycles since their most recent pregnancy. Thus, rather than tracking the potential differences in fitness between females, male baboons appear to track and target the potential for a given reproductive opportunity to result in fertilization.
Data from: Testing for beneficial reversal of dominance during salinity shifts in the invasive copepod Eurytemora affinis, and implications for the maintenance of genetic variation
Maintenance of genetic variation at loci under selection has profound implications for adaptation under environmental change. In temporally and spatially varying habitats, non-neutral polymorphism could be maintained by heterozygote advantage across environments (marginal overdominance), which could be greatly increased by beneficial reversal of dominance across conditions. We tested for reversal of dominance and marginal overdominance in salinity tolerance in the salt-to-freshwater invading copepod Eurytemora affinis. We compared survival of F1 offspring generated by crossing saline and freshwater inbred lines (between-salinity F1 crosses) relative to within-salinity F1 crosses, across three salinities. We found evidence for both beneficial reversal of dominance and marginal overdominance in salinity tolerance. In support of reversal of dominance, survival of between-salinity F1 crosses was not different from that of freshwater F1 crosses under freshwater conditions and saltwater F1 crosses under saltwater conditions. In support of marginal overdominance, between-salinity F1 crosses exhibited significantly higher survival across salinities relative to both freshwater and saltwater F1 crosses. Our study provides a rare empirical example of complete beneficial reversal of dominance associated with environmental change. This mechanism might be crucial for maintaining genetic variation in salinity tolerance in E. affinis populations, allowing rapid adaptation to salinity changes during habitat invasions.
Data from: Testing alternative hypotheses for evolutionary diversification in an African songbird: rainforest refugia versus ecological gradients
Geographic isolation in rainforest refugia and local adaptation to ecological gradients may both be important drivers of evolutionary diversification. However, their relative importance and the underlying mechanisms of these processes remain poorly understood because few empirical studies address both putative processes in a single system. A key question is to what extent is divergence in signals that are important in mate and species recognition driven by isolation in rainforest refugia or by divergent selection across ecological gradients? We studied the little greenbul, Andropadus virens, an African songbird, in Cameroon and Uganda, to determine whether refugial isolation or ecological gradients better explain existing song variation. We then tested whether song variation attributable to refugial or ecological divergence was biologically meaningful using reciprocal playback experiments to territorial males. We found that much of the existing song variation can be explained by both geographic isolation and ecological gradients, but that divergence across the gradient, and not geographic isolation, affects male response levels. These data suggest that ecologically divergent traits, independent of historical isolation during glacial cycles, can promote reproductive isolation. Our study provides further support for the importance of ecology in explaining patterns of evolutionary diversification in ecologically diverse regions of the planet.
Data from: A test of male infanticide as a reproductive tactic in a cichlid fish
Infanticide and offspring cannibalism are taxonomically widespread phenomena. In some group-living species, a new dominant individual taking over a group can benefit from infanticide if doing so induces potential mates to become reproductively available sooner. Despite widespread observations of infanticide (i.e. egg cannibalism) among fishes, no study has investigated whether egg cannibalism occurs in fishes as a result of group takeovers, or how this type of cannibalism might be adaptive. Using the cooperatively breeding cichlid, Neolamprologus pulcher, we tested whether new unrelated males entering the dominant position in a social group were more likely to cannibalize eggs, and whether such cannibalism would shorten the interval until the female's next spawning. Females spawned again sooner if their broods were removed than if they were cared for. Egg cannibalism occurred frequently after a group takeover event, and was rarer if the original male remained with the group. While dominant breeder females were initially highly aggressive towards newcomer males that took over the group, the degree of resistance depended on relative body size differences between the new pair and, ultimately, female aggression did not prevent egg cannibalism. Egg cannibalism, however, did not shorten the duration until subsequent spawning, or increase fecundity during subsequent breeding in our laboratory setting. Our results show that infanticide as mediated through group takeovers is a taxonomically widespread behaviour.
Data from: Testing the association of phenotypes with polyploidy: An example using herbaceous and woody eudicots
Although numerous studies have surveyed the frequency with which different plant characters are associated with polyploidy, few statistical tools are available to identify the factors that potentially facilitate polyploidy. We describe a new probabilistic model, BiChroM, designed to associate the frequency of polyploidy and chromosomal change with a binary phenotypic character in a phylogeny. BiChroM provides a robust statistical framework for testing differences in rates of polyploidy associated with phenotypic characters along a phylogeny while simultaneously allowing for evolutionary transitions between character states. We used BiChroM to test whether polyploidy is more frequent in woody or herbaceous plants, based on tree with 4,711 eudicot species. Although polyploidy occurs in woody species, rates of chromosome doubling were over six times higher in herbaceous species. Rates of single chromosome increases or decreases were also far higher in herbaceous than woody species. Simulation experiments indicate that BiChroM performs well with little to no bias and relatively little variance at a wide range of tree depths when trees have at least 500 taxa. Thus, BiChroM provides a first step towards a rigorous statistical framework for assessing the traits that facilitate polyploidy.
Data from: North Atlantic Gateway: test bed of deep-sea macroecological patterns
Aim: The deep waters around Iceland, known as the North Atlantic Gateway, constitute an ideal location to investigate deep-sea ecological hypotheses. Using ostracods, we constructed a comprehensive deep-sea macroecological dataset of the North Atlantic Gateway region and investigated the controlling factors of large-scale, deep-sea species diversity patterns. Location: Sub-polar North Atlantic Ocean Time period: Modern Major taxa studied: Ostracoda (Crustacea) Methods: We investigated deep-sea biodiversity patterns and applied ecological modeling (multiple regression and model averaging) to test whether these patterns are governed by environmental factors such as temperature, surface primary productivity, and seasonality. Beta diversity analyses were applied to evaluate the effect of a geographical barrier (Greenland-Iceland-Faeroe Ridge) on deep-sea benthic faunal distributions. Results: We constructed a deep-sea macroecological dataset with 32 stations, 5676 specimens, and 122 species. We confirmed a linear latitudinal diversity gradient with higher diversity in the North Atlantic proper than in the Nordic Seas. We report a unimodal depth diversity gradient south of the ridge, but a linear diversity-decline with depth north of the ridge. The turnover component of beta diversity increased toward the ridge. Main conclusions: We found both temperature and surface primary production are important for deep-sea biodiversity. For the first time, we report a significant diversity-temperature relationship in both macroecological (spatial; this study) and existing paleoecological (time-series) data for the same taxa. In addition to temperature and surface primary production, bathymetric features such as a shallow ridge acting as a barrier, are an important factor for deep-sea biodiversity distribution. The low diversity of the Nordic Seas is likely due to a combination of low temperatures and bathymetric barriers. These results substantially expand our understanding of the well-known yet poorly understood Greenland-Iceland-Faeroe Ridge faunal transition with possible insight to its cause.
Data from: HIV testing in a South African emergency department: a missed opportunity
Background: South Africa (SA) has the highest burden of HIV infection in the world. Even though HIV testing is mandated in all hospital-based facilities in SA, it is rarely implemented in the emergency department (ED). EDs are episodic care centers that provide care to large volumes of undifferentiated patients for short periods of time, and may treat undiagnosed HIV-infected patients not captured through standard clinic based screenings. Methods and Findings: In this prospective study, we implemented the National South African HIV testing guidelines, including 24-hours a day counselor initiated HIV Counseling and Testing (HCT), at Frere Hospital in the Eastern Cape from September 1 to November 30, 2016. All patients that presented for care in the ED during the study period, and who were clinically stable and fully conscious, were eligible to be approached by HCT staff to receive a rapid point-of-care HIV test. A total of 2355 of the 9583 (24.6%) patients that presented to the ED for care during the study period were approached by the HCT staff, of whom 1852 were enrolled in the study. There was high uptake of HIV testing (78.6%) among a predominantly male (58%) patient group that mostly presented with traumatic injuries (70.8%). Four hundred (21.6%) of the enrolled patients were HIV positive, including 115 (6.2%) with previously undiagnosed HIV infection. The overall prevalence of HIV infection in females (29.8%) was twice that compared to males (15.4%), despite the burden of undiagnosed infection being similar (6.0% for all females and 6.4% for all males). Conclusions: Overall there was a high HIV testing uptake that revealed a significant burden of undiagnosed HIV infection in this setting, especially in young males. Future research should focus on testing optimization, and efficient linkage to care from the ED for antiretroviral therapy initiation.
Data from: Global test of Eltonian niche conservatism of nonnative freshwater fish species between their native and introduced ranges
Despite growing evidence that biotic interactions limit the distribution of species and their potential redistribution under climate change, the recent surge of interest in niche conservatism has predominantly focused on the Grinellian (abiotic) niche, whereas few studies have attempted to quantify potential lability in the Eltonian (biotic or trophic) niche. Here, we test for conservatism in the Eltonian niche of 32 freshwater fish species between their introduced and native ranges from 435 populations across the globe. We used stable isotope data to quantify niche shifts along the horizontal (δ13C: indicating the origin of the resources consumed) and vertical (δ15N: describing the trophic position) dimensions of the isotopic niche, as well as shifts in overall isotopic niche breadth. Using an assemblage centroid standardized isotope vector analysis and controlling for phylogenetic relatedness among species, we demonstrated that introduced freshwater fishes exhibited flexibility in both resource use and trophic position that was beyond levels of natural variability observed in their native ranges. By contrast, niche breadth showed variability only within the limits recorded in native populations and varied independently from shifts in mean isotopic niche positions. Across all species and introduction histories, we found a consistent shift towards more balanced acquisition of resources with mixed origins and at intermediate trophic positions, suggesting a general mechanism by which fish species successfully establish into recipient communities. The mechanisms that promote or inhibit species from shifting their Eltonian niche remains unknown, but trophic flexibility is likely to contribute to both the success and the ecological impacts of invasive species and range shifts of native species under future global change.
Data from: Testing the prey-trap hypothesis at two wildlife conservancies in Kenya
Protecting an endangered and highly poached species can conflict with providing an open and ecologically connected landscape for coexisting species. In Kenya, about half of the black rhino (Diceros bicornis) live in electrically fenced private conservancies. Purpose-built fence-gaps permit some landscape connectivity for elephant while restricting rhino from escaping. We monitored the usage patterns at these gaps by motion-triggered cameras and found high traffic volumes and predictable patterns of prey movement. The prey-trap hypothesis (PTH) proposes that predators exploit this predictable prey movement. We tested the PTH at two semi-porous reserves using two different methods: a spatial analysis and a temporal analysis. Using spatial analysis, we mapped the location of predation events with GPS and looked for concentration of kill sites near the gaps as well as conducting clustering and hot spot analysis to determine areas of statistically significant predation clustering. Using temporal analysis, we examined the time lapse between the passage of prey and predator and searched for evidence of active prey seeking and/or predator avoidance. We found no support for the PTH and conclude that the design of the fence-gaps is well suited to promoting connectivity in these types of conservancies.
Data from: Testing for ancient adaptive radiations in Neotropical cichlid fishes
Most contemporary studies of adaptive radiation focus on relatively recent and geographically restricted clades. It is less clear whether diversification of ancient clades spanning entire continents is consistent with adaptive radiation. We used novel fossil calibrations to generate a chronogram of Neotropical cichlid fishes and to test whether patterns of lineage and morphological diversification are congruent with hypothesized adaptive radiations in South and Central America. We found that diversification in the Neotropical cichlid clade and the highly diverse tribe Geophagini was consistent with diversity-dependent, early bursts of divergence followed by decreased rates of lineage accumulation. South American Geophagini underwent early rapid differentiation in body shape, expanding into novel morphological space characterized by elongate-bodied predators. Divergence in head-shape attributes associated with trophic specialization evolved under strong adaptive constraints in all Neotropical cichlid clades. The South American Cichlasomatini followed patterns consistent with constant rates of morphological divergence. Although morphological diversification in South American Heroini was limited, Eocene invasion of Central American habitats was followed by convergent diversification mirroring variation observed in Geophagini. Diversification in Neotropical cichlids was influenced by the early adaptive radiation of Geophagini, which potentially limited differentiation in other cichlid clades.
Data from: Conspicuous female ornamentation and tests of male mate preference in threespine sticklebacks (Gasterosteus aculeatus)
Sexual selection drives the evolution of exaggerated male ornaments in many animal species. Female ornamentation is now acknowledged also to be common but is generally less well understood. One example is the recently documented red female throat coloration in some threespine stickleback (Gasterosteus aculeatus) populations. Although female sticklebacks often exhibit a preference for red male throat coloration, the possibility of sexual selection on female coloration has been little studied. Using sequential and simultaneous mate choice trials, we examined male mate preferences for female throat color, as well as pelvic spine color and standard length, using wild-captured threespine sticklebacks from the Little Campbell River, British Columbia. In a multivariate analysis, we found no evidence for a population-level mate preference in males, suggesting the absence of directional sexual selection on these traits arising from male mate choice. Significant variation was detected among males in their preference functions, but this appeared to arise from differences in their mean responsiveness across mating trials and not from variation in the strength (i.e., slope) of their preference, suggesting the absence of individual-level preferences as well. When presented with conspecific intruder males, male response decreased as intruder red throat coloration increased, suggesting that males can discriminate color and other aspects of phenotype in our experiment and that males may use these traits in intrasexual interactions. The results presented here are the first to explicitly address male preference for female throat color in threespine sticklebacks.
Data from: Can collective memories shape fish distributions? A test, linking space-time occurrence models and population demographics
Social learning can be fundamental to cohesive group living, and schooling fishes have proven ideal test subjects for recent work in this field. For many species, both demographic factors, and inter- (and intra-) generational information exchange are considered vital ingredients in how movement decisions are reached. Yet key information is often missing on the spatial outcomes of such decisions, and questions concerning how migratory traditions are influenced by collective memory, density-dependent and density-independent processes remain open. To explore these issues, we focused on Atlantic herring (Clupea harengus), a long-lived, dense-schooling species of high commercial importance, noted for its unpredictable shifts in winter distribution, and developed a series of Bayesian space-time occurrence models to investigate wintering dynamics over 23 years, using point-referenced fishery and survey records from Icelandic waters. We included covariates reflecting local-scale environmental factors, temporally-lagged prey biomass and recent fishing activity, and through an index capturing distributional persistence over time, derived two proxies for spatial memory of past wintering sites. The previous winter's occurrence pattern was a strong predictor of the present pattern, its influence increasing with adult population size. Although the mechanistic underpinnings of this result remain uncertain, we suggest that a 'wisdom of the crowd' dynamic may be at play, by which navigational accuracy towards traditional wintering sites improves in larger and/or denser, better synchronized schools. Wintering herring also preferred warmer, fresher, moderately stratified waters of lower velocity, close to hotspots of summer zooplankton biomass, our results indicative of heightened environmental sensitivity in younger cohorts. Incorporating spatiotemporal correlation structure and time-varying regression coefficients improved model performance, and validation tests on independent observations one-year ahead illustrate the potential of uniting demographic information and non-stationary models to quantify both the strength of collective memory in animal groups and its relevance for the spatial management of populations.
Data from: A chromosome 5q31.1 locus associates with tuberculin skin test reactivity in HIV-positive individuals from tuberculosis hyper-endemic regions in east Africa
One in three people has been infected with Mycobacterium tuberculosis (MTB), and the risk for MTB infection in HIV-infected individuals is even higher. We hypothesized that HIV-positive individuals living in tuberculosis-endemic regions who do not get infected by Mycobacterium tuberculosis are genetically resistant. Using an "experiment of nature" design that proved successful in our previous work, we performed a genome-wide association study of tuberculin skin test positivity using 469 HIV-positive patients from prospective study cohorts of tuberculosis from Tanzania and Uganda to identify genetic loci associated with MTB infection in the context of HIV-infection. Among these individuals, 244 tested were tuberculin skin test (TST) positive either at enrollment or during the >8 year follow up, while 225 were not. We identified a genome-wide significant association between the dominant model of rs877356 and binary TST status in the combined cohort (OR=0.2671, p=1.22x10-8). Association was replicated with similar significance when examining TST induration as a continuous trait. The variant lies in the 5q31.1 region, 57kb downstream from IL9. Two-locus analyses of association of variants near rs877356 showed a haplotype comprised of rs877356 and an IL9 missense variant rs2069885 had the most significant association (p=1.59x10-12). We also replicated previously linked loci on chromosomes 2, 5, and 11. IL9 is a cytokine produced by mast cells and T¬H2 cells during inflammatory responses, providing a possible link between airway inflammation and protection from MTB infection. Our results indicate that studying uninfected participants with extensive exposure increases the power to detect associations in complex infectious disease.
Data from: Empirical tests of harvest-induced body-size evolution along a geographic gradient in Australian macropods
1. Life-history theory predicts the progressive dwarfing of animal populations that are subjected to chronic mortality stress but the evolutionary impact of harvesting terrestrial herbivores has seldom been tested. In Australia, marsupials of the genus Macropus (kangaroos and wallabies) are subjected to size-selective commercial harvesting. Mathematical modelling suggests that harvest quotas (ca. 10–20 % of population estimates annually) could be driving body-size evolution in these species. 2. We tested this hypothesis for three harvested macropod species with continental-scale distributions. To do so, we measured more than 2 000 macropod skulls sourced from wildlife collections spanning the last 130 years. We analysed these data using spatial Bayesian models that controlled for the age and sex of specimens as well as environmental drivers and island effects. 3. We found no evidence for the hypothesized decline in body size for any species; rather, models that fit trend terms supported minor body size increases over time. This apparently counterintuitive result is consistent with reduced mortality due to a depauperate predator guild and increased primary productivity of grassland vegetation following European settlement in Australia. 4. Spatial patterns in macropod body size supported the heat dissipation limit and productivity hypotheses proposed to explain geographic body-size variation (i.e., skull size increased with decreasing summer maximum temperature and increasing rainfall, respectively). 5. There is no empirical evidence that size-selective harvesting has driven the evolution of smaller body size in Australian macropods. Bayesian models are appropriate for investigating the long-term impact of human harvesting because they can impute missing data, fit non-linear growth models and account for non-random spatial sampling inherent in wildlife collections.
Data from: Genomic tests of the species-pump hypothesis: recent island connectivity cycles drive population divergence but not speciation in Caribbean crickets across the Virgin Islands
Harnessing the power of genomic scans, we test the debated 'species pump' hypothesis that implicates repeated cycles of island connectivity and isolation as drivers of divergence. This question has gone understudied given the limited resolution of past molecular markers for studying such dynamic phenomena. With an average of 32000 SNPs from the genome of 136 individuals from ten populations of a Caribbean flightless ground cricket species (Amphiacusta sanctaecrucis) and a complementary set of statistical approaches, we infer a stepping-stone colonization model and high levels of genetic differentiation across the Virgin Islands, which have been periodically inter-connected until 8 ka. Estimates of divergence times from models based on the site frequency spectrum coincide with a period of repeated connection and fragmentation of the islands at 75–130 ka. These results are consistent with a role of island connectivity cycles in promoting genomic divergence and indicate that the genetic distinctiveness of island populations has persisted despite subsequent and extended interisland connections identified from bathymetric data. We discuss these findings in the broader context of Caribbean biogeography, and more specifically why high levels of genomic divergence across the Virgin Islands associated with repeated connectivity cycles do not actually translate into species diversification.
Data from: Does predation risk affect mating behavior? An experimental test in dumpling squid (Euprymna tasmanica)
Introduction: One of the most important trade-offs for many animals is that between survival and reproduction. This is particularly apparent when mating increases the risk of predation, either by increasing conspicuousness, reducing mobility or inhibiting an individual's ability to detect predators. Individuals may mitigate the risk of predation by altering their reproductive behavior (e.g. increasing anti-predator responses to reduce conspicuousness). The degree to which individuals modulate their reproductive behavior in relation to predation risk is difficult to predict because both the optimal investment in current and future reproduction (due to life-history strategies) and level of predation risk may differ between the sexes and among species. Here, we investigate the effect of increased predation risk on the reproductive behavior of dumpling squid (Euprymna tasmanica). Results: Females, but not males, showed a substantial increase in the number of inks (an anti-predator behavior) before mating commenced in the presence of a predator (sand flathead Platycephalus bassensis). However, predation risk did not affect copulation duration, the likelihood of mating, female anti-predator behavior during or after mating or male anti-predator behavior at any time. Conclusions: Inking is a common anti-predator defense in cephalopods, thought to act like a smokescreen, decoy or distraction. Female dumpling squid are probably using this form of defense in response to the increase in predation risk prior to mating. Conversely, males were undeterred by the increase in predation risk. A lack of change in these variables may occur if the benefit of completing mating outweighs the risk of predation. Prioritizing current reproduction, even under predation risk, can occur when the chance of future reproduction is low, there is substantial energetic investment into mating, or the potential fitness payoffs of mating are high.
Data from: Variation in growth drives the duration of parental care: a test of Ydenberg's model
The duration of parental care in animals varies widely, from none to lifelong. Such variation is typically thought to represent a trade-off between growth and safety. Seabirds show wide variation in the age at which offspring leave the nest, making them ideal to test the idea that a trade-off between high energy gain at sea and high safety at the nest drives variation in departure age (Ydenberg's model). To directly test the model assumptions, we attached time-depth recorders to murre parents (fathers [which do all parental care at sea] and mothers; of each). Except for the initial mortality experienced by chicks departing from the colony, the mortality rate at sea was similar to the mortality rate at the colony. However, energy gained by the chick per day was ∼2.1 times as high at sea compared with at the colony because the father spent more time foraging, since he no longer needed to spend time commuting to and from the colony. Compared with the mother, the father spent ∼2.6 times as much time diving per day and dived in lower-quality foraging patches. We provide a simple model for optimal departure date based on only (1) the difference in growth rate at sea relative to the colony and (2) the assumption that transition mortality from one life-history stage to the other is size dependent. Apparently, large variation in the duration of parental care can arise simply as a result of variation in energy gain without any trade-off with safety.
Data from: A continent-scale test of multiple hypotheses on the abundances of Neotropical birds
Explaining variation in the abundance of species remains a challenge in ecology. We sought to explain variation in abundance of Neotropical forest birds using a dataset of population densities of 596 species. We tested a priori hypotheses for the roles of species traits, environmental factors, and species interactions. Specifically, we focused on four factors: 1) body mass (trait); 2) habitat type (environmental factor), 3) net primary productivity (NPP; environmental factor); and 4) species richness of competitors (species interaction). Body size explained much variation in density, although only when analyzed at higher taxonomic levels. Habitat type was a strong predictor of density. The relationship between density and productivity was weak. Densities were related negatively to the species richness of heterospecifics, however – this trend was particularly strong within closely related groups. Our results show that the influence of energetic factors such as body size and productivity depends on phylogeny, and they act through indirect relations with other variables; alternative ecological factors such as habitat structure and species interactions play a more direct and stronger role in determining abundance than previously thought.
Data from: Testing macroecological abundance patterns: the relationship between local abundance and range size, range position and climatic suitability among European vascular plants
<p><strong>Aim: </strong>A fundamental question in macroecology centres around understanding the relationship between species' local abundance and their distribution in geographic and climatic space (i.e. the multi-dimensional climatic space or climatic niche). Here, we tested three macroecological hypotheses that link local abundance to the following range properties: (1) the abundance-range size relationship, (2) the abundance-range centre relationship, and (3) the abundance-suitability relationship.<br> <br> <strong>Location: </strong>Europe<br> <br> <strong>Taxon: </strong>Vascular plants<br> <br> <strong>Methods:</strong> Distribution range maps were extracted from the Chorological Database to derive information on the range and niche sizes of 517 European vascular plant species. To estimate local abundance, we assessed samples from 744,513 vegetation plots in the European Vegetation Archive, where local species' abundance is available as plant cover per plot. We then calculated the 'centrality', i.e. the distance between the location of the abundance observation and each species' range centre in geographic and climatic space. The climatic suitability of plot locations was estimated using coarse-grain species distribution models (SDMs). The relationships between centrality or climatic suitability with abundance were tested using linear models and quantile regression. We summarized the overall trend across species' regression slopes from linear models and quantile regression using a meta-analytical approach.<br> <br> <strong>Results: </strong>We did not detect any positive relationships between a species' mean local abundance and the size of its geographic range or climatic niche. Contrasting yet significant correlations were detected between abundance and centrality or climatic suitability among species.<br> <br> <strong>Main conclusions:</strong> Our results do not provide unequivocal support for any of the relationships tested, demonstrating that determining properties of species' distributions at large grains and extents might be of limited use for predicting local abundance, including current SDM approaches. We conclude that environmental factors influencing individual performance and local abundance are likely to differ from those factors driving plant species' distribution at coarse resolution and broad geographic extents.</p>
Data from: Do respiratory limitations affect metabolism of insect larvae before moulting: an empirical test at the individual level
Recent data suggest that oxygen limitation may induce moulting in larval insects. This oxygen dependent induction of moulting (ODIM) hypothesis stems from the fact that the tracheal respiratory system of insects grows primarily at moults, whereas tissue mass increases massively between moults. This may result in a mismatch between oxygen supply and demand at the end of each larval instar because oxygen demand of growing tissues exceeds the relatively fixed supply capacity of the respiratory system. The ODIM hypothesis predicts that, within larval instars, respiration and metabolic rates of an individual larva first increase with increasing body mass but eventually level off once the supply capacity of the tracheal system starts to constrain metabolism. Here, we provide the first individual-level test of this key prediction of the ODIM hypothesis. We use a novel methodology where we repeatedly measure respiration and metabolic rates throughout the penultimate- and final-instar larvae in the butterfly Pieris napi. In the penultimate instar, respiration and metabolic rates gradually decelerated along with growth, supporting the ODIM hypothesis. However, respiration and metabolic rates increased linearly during growth in the final instar, contradicting the prediction. Moreover, our data suggest considerable variation among individuals in the association between respiration rate and mass in the final instar. Overall, the results provide partial support for the ODIM hypothesis and suggest that oxygen limitation may emerge gradually within a larval instar. The results also suggest that there may be different moult induction mechanisms in larva-to-larva moults compared to the final metamorphic moult.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.