Find research datasets worth reusing

Data from: Populating a continent: Phylogenomics reveal the timing of Australian frog diversification

The Australian continent's size and isolation make it an ideal place for studying the accumulation and evolution of biodiversity. Long separated from the ancient supercontinent Gondwana, most of Australia's plants and animals are unique and endemic, including the continent's frogs. Australian frogs comprise a remarkable ecological and morphological diversity categorized into a small number of distantly related radiations. We present a phylogenomic hypothesis based on an exon-capture dataset that spans the main clades of Australian myobatrachoid, pelodryadid hyloid, and microhylid frogs. Our time-calibrated phylogenomic-scale phylogeny identifies great disparity in the relative ages of these groups which vary from Gondwanan relics to recent immigrants from Asia and include arguably the continent's oldest living vertebrate radiation. This age stratification provides insight into the colonization of⁠, and diversification on, the Australian continent through deep time, during periods of dramatic climatic and community changes. Contemporary Australian frog diversity highlights the adaptive capacity of anurans, particularly in response to heat and aridity, and explains why they are one of the continent's most visible faunas.

Data from: The costs of living on the coast: reduction in body size and size-specific reproductive output in coastal populations of a widespread amphibian

<ol> <li>Body size is a critical component of organismal biology. Body size is known to be influenced by a plethora of environmental conditions, among which exposure to large-scale variations of salinity has been comparatively overlooked. Yet, exposure to salinity is known to affect energetic allocation toward growth and reproduction.</li> <li>In this study, we investigated the morphological differences between inland and coastal individuals of spined toads (Bufo spinosus) in Western France. </li> <li>We measured adult morphology both outside and during the reproductive season on 190 individuals, and assessed reproduction in pairs originating from inland (N=20) and coastal (N=30) environments.</li> <li>Overall, we found that adult coastal toads were smaller and lighter than inland individuals. Reproductive correlates of these differences included lower fecundity and smaller egg size (but higher egg density) in coastal females. Interestingly, these differences were not allometric correlates of body size, as coastal females invested proportionally less in all components of reproduction (fecundity, egg size and egg protection).</li> <li>These results suggest altered resource allocation to growth and reproduction in coastal amphibians, which may be related to the marked spatial gradient of salinity (measured in reproductive ponds) and the associated costs of osmoregulation (higher osmolality in coastal individuals), for which local adaptation and higher tolerance to salinity remains to be tested.</li> </ol>

Data for: Responses to saltwater exposure vary across species, populations, and life-stages in anuran amphibians

To predict the impacts of environmental change on species, we must first understand the factors that limit the present-day ranges of species. Most anuran amphibians cannot survive at elevated salinities, which may drive their distribution in coastal locations. Previous research showed that coastal Hyla cinerea are locally adapted to brackish habitats in North Carolina (USA). Although Hyla squirella and Hyla chrysoscelis both inhabit coastal wetlands nearby, they have not been observed in saline habitats. We take advantage of naturally occurring microgeographic variation in coastal wetland occupancy exhibited by these congeneric treefrog species to explore how salt exposure affects oviposition site choice, hatching success, early tadpole survival, plasma osmolality, and tadpole body condition across coastal and inland locations. We observed higher survival among coastal H. cinerea tadpoles than inland H. cinerea, which corroborates previous findings. But contrary to expectations, coastal H. cinerea had lower survival than H. squirella and H. chrysoscelis, indicating that all three species may be able to persist in saline wetlands. We also observed differences in tadpole plasma osmolality across species, locations, and salinities, but these differences were not associated with survival rates in saltwater. Instead, coastal occupancy may be affected by stage-specific processes like higher probability of total clutch loss as shown by inland H. chrysoscelis or maladaptive egg deposition patterns as shown by inland H. squirella. Although we expected saltwater to be the primary filter driving species distributions along a coastal salinity gradient, it is likely that the factors dictating anuran ranges along the coast involve stage-, species-, and location specific processes that are mediated by ecological processes and life history traits.

Sample extraction and SNP sequencing data for: Identification of sex-linked SNP markers in wild populations of monomorphic birds

Single-nucleotide polymorphism (SNP) analyses are a powerful tool for population genetics, pedigree reconstruction and phenotypic trait mapping. However, the untapped potential of SNP markers to discriminate the sex of individuals in species with reduced sexual dimorphism or of individuals during immature stages remains a largely unexplored avenue. Here, we develop a novel protocol for molecular sexing of birds based on the detection of unique Z- and W-linked SNP markers. Our method is based on the identification of two unique loci, one in each sexual chromosome. Individuals are considered males when they show no calls for the W-linked SNP and are heterozygotic or homozygotic for the Z-linked SNP, while females show both Z- and W-linked SNP calls. We validated the method in the Jackdaw (Corvus monedula). The reduced sexual dimorphism in this species makes it difficult to sex individuals in the wild. We assessed the reliability of the method using 36 individuals of known sex and found that their sex was correctly assigned in 100% of cases. The sex-linked markers also proved to be widely applicable to discriminate males and females from a sample of 927 genotyped individuals of different maturity stages with an accuracy of 99.5%. Given that SNP markers are increasingly used in quantitative genetic analyses of wild populations, the approach we propose has a great potential to be integrated into broader genetic research programmes without the need for additional sexing techniques.

Data from: Philopatry influences the genetic population structure of the blacktip shark (Carcharhinus limbatus) at multiple spatial scales

Understanding how interactions among microevolutionary forces generate genetic population structure of exploited species is vital to the implementation of management policies that facilitate population persistence. Philopatry displayed by many coastal shark species can impact gene flow and facilitate selection, and thus has direct implications for the spatial scales of management plans. Here, genetic structure of the blacktip shark (Carcharhinus limbatus) was examined using a mixed-marker approach based on mitochondrial control region sequences and 4,339 SNP-containing loci generated using ddRAD-Seq. Genetic variation was assessed among young-of-the-year sampled in 11 sites in waters of the United States in the western North Atlantic Ocean, including the Gulf of Mexico. Spatial and environmental analyses detected 68 nuclear loci putatively under selection, enabling separate assessments of neutral and adaptive genetic structure. Both mitochondrial and neutral SNP data indicated three genetically distinct units – the Atlantic, eastern Gulf, and western Gulf – that align with regional stocks and suggest regional philopatry by males and females. Heterogeneity at loci putatively under selection, associated with temperature and salinity, was observed among sites within Gulf units, suggesting local adaptation. Furthermore, five pairs of siblings were identified in the same site across timescales corresponding with female reproductive cycles. This indicates that females re-used a site for parturition, which has the potential to facilitate the sorting of adaptive variation among neighboring sites. The results demonstrate differential impacts of microevolutionary forces at varying spatial scales and highlight the importance of conserving essential habitats to maintain sources of adaptive variation that may buffer species against environmental change.

Data from: Phylogenetic, population structure, and population demographic analyses reveal that Vicia sepium in Japan is native and not introduced

Vicia sepium (bush vetch) is a perennial legume widely distributed throughout the Eurasian continent. However, its distribution in Japan is limited to Mt. Ibuki and small parts of central and southern Hokkaido. Therefore, each Japanese V. sepium lineage has been considered to have been introduced separately from Europe. Here, we examined whether the species was introduced or not on the basis of cpDNA sequences and genome-wide SNPs from Japanese and overseas samples. Both the cpDNA haplotype network and the nuclear DNA phylogenetic tree showed that Japanese V. sepium is monophyletic. Furthermore, although the nuclear DNA phylogenetic tree also showed that each lineage is clearly monophyletic, genetic admixture of the genetic cluster dominated in the Hokkaido lineage was also detected in the Mt. Ibuki lineage. Population divergence analysis showed that the two lineages diverged during the last glacial period. The Mt. Ibuki lineage showed a sudden population decline 300–400 years ago, indicating that some anthropogenic activity might be involved, while the Hokkaido lineage showed a gradual population decline from 5,000 years ago. Consequently, these two lineages show low current genetic diversity compared with overseas lineages. These results show that the Japanese V. sepium is not introduced but is native.

opencc-zeroDec 2022View details →

Data from: Past population control biases interpretations of contemporary genetic data: implications for future invasive Sitka black-tailed deer management in Haida Gwaii

Invasive species management practices often include genetic analyses to better inform decision-making and resource allocation. Yet, past management actions may artificially bias recovered patterns of genetic variation; for example, a population bottleneck caused by contemporary culling may mirror some patterns associated with historical isolation. Here, we aimed to disentangle the impacts of past management activities from natural processes for Sitka black-tailed deer (Odocoileus hemionus sitkensis), an invasive species that has been repeatedly culled on two islands, SGang Gwaay and Reef, within the Haida Gwaii archipelago (Canada). We applied a recently developed Genotyping-in-Thousands by sequencing panel to contemporary (e.g., blood, serum, tissue, muscle, feces) and archived deer samples, the latter collected prior to management activity within the system (c. 1997–1998), which allowed us to contextualize conflicting patterns of isolation and connectivity previously observed on SGang Gwaay and Reef. Successful genotyping (92.6%) and population genetic analysis of 292 individuals at 236 SNPs revealed signals of historical isolation on SGang Gwaay and Reef, provided evidence of a founder effect during initial colonization, and indicated an absence of ongoing gene flow. Furthermore, our spatiotemporal analyses consistently supported a priori predictions associated with bottlenecks within post-cull populations, such as within-island loss of genetic variation, elevated within-island kinship, and increased levels of among-island genetic differentiation. These findings are promising for future management of deer on SGang Gwaay and Reef, suggesting that eradications on these islands may be durable. More broadly, our work highlights the importance of understanding management history before interpreting contemporary population genetic data.

zenodo36/100

Population dynamics and seasonal migration patterns of Spodoptera exigua in northern China based on 11 years of monitoring data

The beet armyworm, Spodoptera exigua (Hübner) is an important migratory pest worldwide that has caused serious economic losses in the main crop-producing areas of China. To effectively monitor and control this pest, it is necessary to investigate its interannual and seasonal migration patterns in northern China. In this study, we weekly monitored the population dynamics of S. exigua using sex pheromone traps in Shenyang, Liaoning Province from 2012 to 2022 and simulated the migration trajectories using the HYSPLIT model. Overall, the migration numbers varied significantly among years, with large migrations in 2018 and 2020 that resulted in a total catch of more than 2000 individuals.

opencc-byAug 2023View details →

Data for: A novel cricket morph has diverged in song and wing morphology across island populations

Divergence of sexual signals between populations can lead to speciation, yet opportunities to study the immediate aftermath of novel signal evolution are rare. The recent emergence and spread of a new mating song, purring, in Hawaiian populations of the Pacific field cricket (Teleogryllus oceanicus) allows us to investigate population divergence soon after the origin of a new signal. Male crickets produce songs with specialized wing structures to attract mates from afar (calling) and entice them to mate when found (courtship). However, in Hawaii, these songs also attract an eavesdropping parasitoid fly (Ormia ochracea) that kills singing males. The novel purring song, produced with heavily modified wing morphology, attracts female crickets but not the parasitoid fly, acting as a solution to this conflict between natural and sexual selection. We've since observed increasing numbers of purring males across Hawaii. In this integrative field study, we investigated the distribution of purring and the proportion of purring males relative to other morphs in six populations on four islands and compared a suite of phenotypic traits (wing morphology, calling song, and courtship song) that make up this novel signal across populations of purring males. We show that purring is found in varying proportions across five, and is locally dominant in four, Hawaiian populations. We also show that calling songs, courtship songs, and wing morphology of purring males differ geographically. Our findings demonstrate the rapid pace of evolution in island populations and provide insights into the emergence and divergence of new sexual signals over time.

Data from: Maximum stem diameter predicts liana population demography

Determining population demographic rates is fundamental to understanding differences in species life-history strategies and their capacity to coexist. Calculating demographic rates, however, is challenging and requires long-term, large-scale censuses. Body size may serve as a simple predictor of demographic rate; can it act as a proxy for demographic rate when those data are unavailable? We tested the hypothesis that maximum body size predicts species' demographic rate using repeated censuses of the 77 most common liana species on the Barro Colorado Island, Panama (BCI) 50-ha plot. We found that maximum stem diameter does predict species' population turnover and demography. We also found that lianas on BCI can grow to the enormous diameter of 635 mm, indicating that they can store large amounts of carbon and compete intensely with tropical canopy trees. This study is the first to show that maximum stem diameter can predict plant species' demographic rates and that lianas can attain extremely large diameters. Understanding liana demography is particularly timely because lianas are increasing rapidly in many tropical forests, yet their species-level population dynamics remain chronically understudied. Determining per-species maximum liana diameters in additional forests will enable systematic comparative analyses of liana demography and potential influence across forest types.

Data from: Arriving late and lean at a stopover site is selected against in a declining migratory bird population

Loss and/or deterioration of refuelling habitats have caused population declines in many migratory bird species, but whether this results from unequal mortality among individuals varying in migration traits remains to be shown. Based on 13 years of body mass and size data of great knots (Calidris tenuirostris) at a stopover site of the Yellow Sea, combined with resightings of individuals marked at this stopover site along the East Asian-Australasian Flyway, we assessed year to year changes in annual apparent survival rates, and how apparent survival differed between migration phenotypes (their i.e. migration timing and fuel stores). The measurements occurred over a period of habitat loss and/or deterioration in this flyway. We found that the annual apparent survival rates of great knots rapidly declined from 2006 to 2018, late-arriving individuals with small fuel stores exhibiting the lowest apparent survival rate. There was an advancement in mean arrival date and an increase in the mean fuel load of stopping birds over the study period. Our results suggest that late-arriving individuals with small fuel loads were selected against. Thus, habitat loss and/or deterioration at staging sites may cause changes in the composition of migratory phenotypes at the population-level.

opencc-by-4.0Feb 2022View details →

zenodo36/100

Data from: Evaluating predator control using two non-invasive population metrics: a camera trap activity index and density estimation from scat genotyping

Includes datasets from the Wimmera and Mallee, Victoria, Australia: - Fox camera trap data used to model activity - Fox scat SECR capture and trap files used to model density

Sequencing data for: Chronosequence of invasion reveals minimal losses of population genomic diversity, niche expansion, and trait divergence in the polyploid, leafy spurge

Rapid evolution may play an important role in the range expansion of invasive species and modify forecasts of invasion, which are the backbone of land management strategies. However, losses of genetic variation associated with colonization bottlenecks may constrain trait and niche divergence at leading range edges, thereby impacting management decisions that anticipate future range expansion. The spatial and temporal scales over which adaptation contributes to invasion dynamics remain unresolved. We leveraged detailed records of the ~130-year invasion history of the invasive polyploid plant, leafy spurge (Euphorbia virgata), across ~500km in Minnesota, U.S.A. We examined the consequences of range expansion for population genomic diversity, niche breadth, and the evolution of germination behavior. Using genotyping-by-sequencing, we found some population structure in the range core, where introduction occurred, but panmixia among all other populations. Range expansion was accompanied by only modest losses in sequence diversity, with small, isolated populations at the leading edge harboring similar levels of diversity to those in the range core. The climatic niche expanded during most of the range expansion, and the niche of the range core was largely non-overlapping with the invasion front. Ecological niche models indicated that mean temperature of the warmest quarter was the strongest determinant of habitat suitability and that populations at the leading edge had the lowest habitat suitability. Guided by these findings, we tested for rapid evolution in germination behavior over the time course of range expansion using a common garden experiment and temperature manipulations. Germination behavior diverged from early to late phases of the invasion, with populations from later phases having higher dormancy at lower temperatures. Our results suggest that trait evolution may have contributed to niche expansion during invasion and that distribution models, which inform future management planning, may underestimate invasion potential without accounting for evolution.

Phenotypic and genetic diversity data recorded in island and mainland populations worldwide

We used this dataset to assess the strength of isolation due to geographic and macroclimatic distance across island and mainland systems, comparing published measurements of phenotypic traits and neutral genetic diversity for populations of plants and animals worldwide. The dataset includes 112 studies of 108 species (72 animals and 36 plants) in 868 island populations and 760 mainland populations, with population-level taxonomic and biogeographic information, totalling 7438 records.

Data from: Novel methods to define invasive procedures at the end-of-life were developed to improve quality of end of life care research: A population-based cohort study in colorectal cancer

Background Understanding the use of invasive procedures (IPs) at the end-of-life (EoL) is important to avoid under- and overtreatment, but epidemiologic analysis is hampered by limited methods to define treatment intent and EoL phase. This study applied novel methods to report IPs at the EoL using a colorectal cancer (CRC) case study. Methods An English population-based cohort of adult patients diagnosed between 2013 and 2015 was used with follow-up to 2018. Procedure intent (curative, non-curative, diagnostic) by cancer site and stage at diagnosis was classified by two surgeons independently. Joinpoint regression modelled weekly rates of IPs for 36 sub-cohorts of patients with incremental survival of 0-36 months. EoL phase was defined by a significant IP rate change before death. Zero-inflated Poisson regression explored associations between IP rates and clinical/sociodemographic variables. Results Of 87,731 patients included, 41,972 (48%) died. 9,492 procedures were classified by intent (interrater agreement 99.8%). Patients received 502,895 IPs (1.39 and 3.36 per person year for survivors and decedents). Joinpoint regression identified significant increases in IPs four weeks before death in those living 3-6 months, and eight weeks before death in those living 7–36 months from diagnosis. 7,908 (18.8%) patients underwent IPs at the EoL, with stoma formation the most common major procedure. Younger age, early-stage disease, men, lower comorbidity, those receiving chemotherapy and living longer from diagnosis were associated with IPs. Conclusions Methods to identify and classify IPs at the EoL were developed and tested within a CRC population. This approach can be now extended and validated to identify potential under- and overtreatment.

Data from: Two focal populations and three regional populations of Sobralia chrysostoma

The dispersal and colonization of plant populations allow species to occupy novel habitats, migrate, and undergo range shifts in response to changing environmental factors and, as such, are fundamental ecological processes for ensuring the long-term persistence of species. Natural landscape disturbance often generates habitats available for colonization. Patterns of colonization and population expansion can be inferred from the levels and partitioning of genetic variation of plant populations with known disturbance histories, such as recent volcanic eruptions. We sampled and mapped 496 individuals from two populations of the colonizing terrestrial orchid, Sobralia chrysostoma, on the 1992 lava flow of Volcán Arenal in central Costa Rica. We used neutral co-dominant markers to genotype individuals and estimate population genetic statistics. Both populations had high mean levels of genetic diversity (P = 100%; AP = 3.31; He = 0.259) suggesting that the lava flow was colonized by numerous individuals that likely originated from multiple source populations. However, significant spatial genetic structure (SGS) was only present in one population at the smallest distance class (≤ 2 m) and was low (r = 0.032). That these large and genetically diverse populations had such low SGS and an absence of SGS respectively is contrary to expectations and differs significantly from the pattern in Epidendrum radicans (Orchidaceae), with which S. chrysostoma is growing sympatrically. Our results suggest that these two populations either consist primarily of immigrant individuals or that seeds produced in situ dispersed over longer distances, thereby producing larger seed shadows and greater overlap of seed shadows.

opencc-by-4.0Sep 2023View details →

zenodo36/100

Supporting data for "Population Genomics of Postglacial Western Eurasia"

This repository contains supplemental data from Allentoft, Sikora et al. "Population Genomics of Postglacial Western Eurasia". The following files are included supplementary_figures/ Hi-res versions of supplementary figures  ibd/ Aggregate total IBD sharing rates between pairs of individuals in the full dataset. Includes auxiliary metadata files to use for IBD-based mixture models (code available at <a href="https://github.com/martinsikora/mixmodel_ibd">https://github.com/martinsikora/mixmodel_ibd</a>) For additional details on data generation, curation and sample metadata please consult the main paper.

Data from: Divergence in the internal genital morphology of females is correlated with divergence in male intromittent structures among populations of a millipede

Our understanding of genital evolution comes largely from studies of male genitalia. Females have received far less attention because of the difficulties inherent in quantifying the shapes of their internal genital structures. Here we combine advances in micro-computed tomography with a new landmark free method of quantifying three-dimensional trait shape, to document patterns of divergence in female genital shape, and the correlated divergence of male genitalia among populations of the millipede Antichiropus variabilis. We used single nucleotide polymorphisms to estimate levels of neutral genetic divergence among seven populations of millipede. Genetic divergence was high and correlated with geographic distance. Comparing phenotypic divergence in genital shape to neutral genetic divergence, we found that genital shape for both females and males has diverged more than would be expected from random drift, consistent with a pattern of directional selection. While there was significant covariation between female and male genital shape across populations, the magnitude of divergence in genital shape between the sexes was not correlated. Our results demonstrate the utility of using three-dimensional scanning technologies to examine female genital traits and add to a small but growing number of studies showing that like male genitalia, female genitalia can be under strong directional selection.

Soil composition, phenotypic and genetic data to: Adaptive differentiation on serpentine soil in diploid versus autotetraploid populations of Biscutella laevigata (Brassicaceae)

Serpentine soils exhibit extreme properties (e.g. high magnesium content) influencing plant growth and survival and have been repeatedly documented to promote adaptive edaphic differentiation in plants. Individuals from four pairs of nearby diploid and autotetraploid populations of Biscutella laevigata sampled on serpentine vs non-serpentine soils in a factorial design are used to assess the genetic and phenotypic changes associated with edaphic origin and ploidy level. Individual samples from natural populations were subjected to soil elemental analysis and genotyping using restriction site-associated DNA sequences (RAD-seq) to link genetic variation with contrasting soils and ploidy levels. In diploids, genetic variation was consistent with demographic contraction and a pattern of isolation by environment with respect to the ratio of calcium / magnesium concentrations, whereas tetraploids presented evidence of expansion with limited edaphic differentiation. The genetic basis of tolerance and adaptation to serpentine was further assessed experimentally on seed-grown individuals from all populations subjected to high (serpentine-like) vs low (control) concentrations of magnesium in hydropony. Fitness-related phenotypic traits under experimental cultivation were consistent with adaptive differentiation among diploid ecotypes but not among the tetraploids that similarly grow in both habitats and consistently present higher investment in roots. Further work comparing experimentally resynthesized polyploids to natural diploids and polyploids has to tease the role of whole genome duplication apart from the impact of post-polyploidy evolution.

Data from: Evolutionarily labile dispersal behavior and discontinuous habitats enhance population differentiation in island vs continentally distributed swallows

The causes of population divergence in vagile groups remain a paradox in evolutionary biology: dispersive species should be able to colonize new areas, a prerequisite for allopatric speciation, but dispersal also facilitates gene flow, which erodes population differentiation. Strong dispersal ability has been suggested to enhance divergence in patchy habitats and inhibit divergence in continuous landscapes, but empirical support for this hypothesis is lacking. Here we compared patterns of population divergence in a dispersive clade of swallows distributed across both patchy and continuous habitats. The Pacific Swallow (Hirundo tahitica) has an insular distribution throughout Southeast Asia and the Pacific, while its sister species, the Welcome Swallow (H. neoxena), has a continental distribution in Australia. We used whole-genome data to demonstrate strong genetic structure and limited introgression among insular populations, but not among continental populations. Demographic models show that historic changes in habitat connectivity have contributed to population structure within the clade. Swallows appear to exhibit evolutionarily labile dispersal behavior in which they reduce dispersal propensity after island colonization despite retaining strong flight ability. Our data support the hypothesis that fragmented habitats enhance population differentiation in vagile groups, and suggest that labile dispersal behavior is a key mechanism underlying this pattern.