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.
3,100
datasets available to search
ShareScore release 0.9.0
Dataset results
3,100 results for “recent”
Data from: Recent natural selection causes adaptive evolution of an avian polygenic trait
We used extensive data from a long-term study of great tits (Parus major) in the United Kingdom and Netherlands to better understand how genetic signatures of selection translate into variation in fitness and phenotypes. We found that genomic regions under differential selection contained candidate genes for bill morphology and used genetic architecture analyses to confirm that these genes, especially the collagen gene COL4A5, explained variation in bill length. COL4A5 variation was associated with reproductive success, which, combined with spatiotemporal patterns of bill length, suggested ongoing selection for longer bills in the United Kingdom. Last, bill length and COL4A5 variation were associated with usage of feeders, suggesting that longer bills may have evolved in the United Kingdom as a response to supplementary feeding.
Data from: The association of feeding behavior with the resistance and tolerance to parasites in recently diverged sticklebacks
Divergent natural selection regimes can contribute to adaptive population divergence, but can be sensitive to human-mediated environmental change. Nutrient loading of aquatic ecosystems, for example, might modify selection pressures by altering the abundance and distribution of resources and the prevalence and infectivity of parasites. Here, we used a mesocosm experiment to test for interactive effects of nutrient loading and parasitism on host condition and feeding ecology. Specifically, we investigated whether the common fish parasite Gyrodactylus sp. differentially affected recently diverged lake and stream ecotypes of three-spined stickleback (Gasterosteus aculeatus). We found that the stream ecotype had a higher resistance to Gyrodactylus sp. infections than the lake ecotype, and that both ecotypes experienced a cost of parasitism, indicated by negative relationships between parasite load and both stomach fullness and body condition. Overall, our results suggest that in the early stages of adaptive population divergence of hosts, parasites can affect host resistance, body condition, and diet.
Data from: Genetic and morphometric evidence for the recognition of several recently synonymized species of trans-Andean Rhamdia (Pisces: Siluriformes: Heptapteridae)
A recent taxonomic revision of the Neotropical catfish genus Rhamdia (Pisces: Siluriformes: Heptapteridae) reduced a number of described species to synonymy, especially under a broadly circumscribed R. quelen. Evidence is presented here from DNA sequence data, external morphology, and morphometrics that argues for the recognition of R. guatemalensis in Central and northern South America and R. saijaensis and R. cinerascens in the Pacific drainages of Colombia and Ecuador, respectively. The DNA data indicate that all trans-Andean samples form a monophyletic group, within which there are separate clades corresponding to R. laticauda and the synonymized R. guatemalensis, R. saijaensis, and R. cinerascens. The morphometric data substantiate the phylogenetic groupings, and in external morphology, each putative species has diagnostic characters. Rhamdia guatemalensis is characterized by insertion of the adipose fin closer to the dorsal fin than to the caudal fin and presence of a conspicuous lateral longitudinal dark band; R. saijaensis is characterized by a small head with head length 20.8–23.4% of standard length and by lacking a lateral longitudinal band; and R. cinerascens is characterized by a large head with head length 25.8–30.1% of standard length, base of the adipose fin 30.3–33.3% of standard length, outer mental barbels extending to the base of the pectoral rays, and presence of a faint lateral longitudinal band. The external morphological differences and phylogenetic relationships indicate that these groups are both recognizable and represent independent lineages, which argue for their recognition as species.
Data from: Recent speciation and elevated Z-chromosome differentiation between sexually monochromatic and dichromatic species of Australian teals
Sex chromosomes potentially have an important role in speciation and often have elevated differentiation between closely related species. In birds, traits associated with male plumage, female mate preference, and hybrid fitness have been linked to the Z-chromosome (females are heterogametic, ZW). We tested for elevated Z-differentiation between two recently diverged species of Australian ducks, the sexually monochromatic grey teal Anas gracilis and the dichromatic chestnut teal A. castanea. Despite prominent morphological differences, these two species are genetically indistinguishable at both mitochondrial DNA (mean ΦST < 0.0001) and 17 autosomal loci (mean ΦST = 0.0056). However, we detected elevated Z-differentiation (mean ΦST = 0.281) and tentative evidence of an island of differentiation on the Z-chromosome. This elevated differentiation was explained by a high frequency of derived alleles in chestnut teal that were absent in grey teal, which parallels independent evidence for a gain in dichromatism from a monochromatic ancestor. Coalescent estimates of demographic history and simulations indicated that the elevated Z-differentiation was unlikely to be explained by neutral processes, but instead supported a role of divergent selection. We discuss evidence for models of speciation with gene flow versus adaptive divergence in the absence of gene flow and find that both hypotheses are plausible explanations of the data. Overall, these teal have the weakest background differentiation documented to date for a species showing a large Z-effect, and they are an excellent model species for studying speciation genomics and the evolution of sexual dichromatism.
Data from: The predictability of genomic changes underlying a recent host shift in Melissa blue butterflies
Despite accumulating evidence that evolution can be predictable, studies quantifying the predictability of evolution remain rare. Here, we measured the predictability of genome-wide evolutionary changes associated with a recent host shift in the Melissa blue butterfly (Lycaeides melissa). We asked whether and to what extent genome-wide patterns of evolutionary change in nature could be predicted (1) by comparisons among instances of repeated evolution, and (2) from SNP $\times$ performance associations in a lab experiment. We delineated the genetic loci (SNPs) most strongly associated with host use in two L. melissa lineages that colonized alfalfa. Whereas most SNPs were strongly associated with host use in none or one of these lineages, we detected a ~two-fold excess of SNPs associated with host use in both lineages. Similarly, we found that host-associated SNPs in nature could also be partially predicted from SNP $\times$ performance (survival and weight) associations in a lab rearing experiment. But the extent of overlap, and thus degree of predictability, was somewhat reduced. Although we were able to predict (to a modest extent) the SNPs most strongly associated with host use in nature (in terms of parallelism and from the experiment), we had little to no ability to predict the direction of evolutionary change during the colonization of alfalfa. Our results show that different aspects of evolution associated with recent adaptation can be more or less predictable, and highlight how stochastic and deterministic processes interact to drive patterns of genome-wide evolutionary change
Data from: Demographic history influences spatial patterns of genetic diversity in recently expanded coyote (Canis latrans) populations
Human-mediated range expansions have increased in recent decades and represent unique opportunities to evaluate genetic outcomes of establishing peripheral populations across broad expansion fronts. Over the past century, coyotes (Canis latrans) have undergone a pervasive range expansion and now inhabit every state in the continental United States. Coyote expansion into eastern North America was facilitated by anthropogenic landscape changes and followed two broad expansion fronts. The northern expansion extended through the Great Lakes region and southern Canada, where hybridization with remnant wolf populations was common. The southern and more recent expansion front occurred approximately 40 years later and across territory where gray wolves have been historically absent and remnant red wolves were extirpated in the 1970s. We conducted a genetic survey at 10 microsatellite loci of 482 coyotes originating from 11 eastern U.S. states to address how divergent demographic histories influence geographic patterns of genetic diversity. We found that population structure corresponded to a north-south divide, which is consistent with the two known expansion routes. Additionally, we observed extremely high genetic diversity, which is atypical of recently expanded populations and is likely the result of multiple complex demographic processes, in addition to hybridization with other Canis species. Finally, we considered the transition of allele frequencies across geographic space and suggest the mid-Atlantic states of North Carolina and Virginia as an emerging contact zone between these two distinct coyote expansion fronts.
Data from: Admixture mapping of male nuptial color and body shape in a recently formed hybrid population of threespine stickleback
Despite recent progress, we still know relatively little about the genetic architecture that underlies adaptation to divergent environments. Determining whether the genetic architecture of phenotypic adaptation follows any predictable patterns requires data from a wide variety of species. However, in many organisms, genetic studies are hindered by the inability to perform genetic crosses in the laboratory or by long generation times. Admixture mapping is an approach that circumvents these issues by taking advantage of hybridization that occurs between populations or species in the wild. Here, we demonstrate the utility of admixture mapping in a naturally occurring hybrid population of threespine sticklebacks (Gasterosteus aculeatus) from Enos Lake, British Columbia. Until recently, this lake contained two species of sticklebacks adapted to divergent habitats within the lake. This benthic-limnetic species pair diverged in a number of phenotypes, including male nuptial coloration and body shape, which were previously shown to contribute to reproductive isolation between them. However, recent ecological disturbance has contributed to extensive hybridization between the species, and there is now a single, admixed population within Enos Lake. We collected over 500 males from Enos Lake and found that most had intermediate nuptial color and body shape. By genotyping males with nuptial color at the two extremes of the phenotypic distribution, we identified seven genomic regions on three chromosomes associated with divergence in male nuptial color. These genomic regions are also associated with variation in body shape, suggesting that tight linkage and/or pleiotropy facilitated adaptation to divergent environments in this benthic-limnetic species pairs.
Data from: Recent speciation and secondary contact in endemic ants
Gene flow is the main force opposing divergent selection, and its effects are greater in populations in close proximity. Thus, complete reproductive isolation between parapatric populations is not expected, particularly in the absence of ecological adaptation and sharp environmental differences. Here, we explore the biogeographical patterns of an endemic ant species, Cataglyphis floricola, for which two colour morphs (black and bicolour) coexist in parapatry throughout continuous sandy habitat in southern Spain. Discriminant analyses of six biometric measurements of male genitalia and 27 cuticular hydrocarbons reveal high differentiation between morphs. Furthermore, the low number of shared alleles derived from nuclear markers (microsatellites) between the morphs at their contact zone suggests the absence of recent gene flow. Mitochondrial DNA (COI) phylogenetic analysis and median-joining networks show that the black morph is basal to the bicolour morph, with unique haplotypes recovered for each morph. Mismatch distribution analysis and Bayesian skyline plots suggest that they are undergoing different demographic changes, with the bicolour and black morphs at demographic equilibrium and expansion, respectively. Thus, our results show complete reproductive isolation between the two colour morphs as evidenced from genetic, chemical and morphological data. We suggest that these divergence events could be explained by historical vicariance during the Pleistocene, in which reproductive traits experienced strong divergent selection between the morphs initiating or culminating speciation.
Data from: Coalescent models characterize sources and demographic history of recent round goby colonization of Great Lakes and inland waters
The establishment and spread of aquatic invasive species is ecologically and economically harmful and a source of conservation concern internationally. Processes of species invasion have traditionally been inferred from observational data of species presence/absence and relative abundance. However, genetic-based approaches can provide valuable sources of inference. Restriction-site associated DNA sequencing was used to identify and genotype single nucleotide polymorphism (SNP) loci for Round Gobies (Neogobius melanostomus) (N=440) from 18 sampling locations in the Great Lakes and in three Michigan, USA drainages (Flint, Au Sable, and Cheboygan River basins). Sampled rivers differed in size, accessibility, and physical characteristics including man-made dispersal barriers. Population levels of genetic diversity and inter-population variance in SNP allele frequency were used in coalescence-based Approximate Bayesian Computation (ABC) to statistically compare models representing competing hypotheses regarding source population, post-colonization dispersal, and demographic history in the Great Lakes and inland waters. Results indicate different patterns of colonization across the three drainages. In the Flint River, models indicate a strong population bottleneck (< 3% of contemporary effective population size) and a single founding event from Saginaw Bay led to the colonization of inland river segments. In the Au Sable River, analyses could not distinguish potential source populations, but supported models indicated multiple introductions from one source population. In the Cheboygan River, supported models indicated that colonization likely proceeded from east (Lake Huron source) to west among inland locales sampled in the system. Despite the recent occupancy of Great Lakes and inland habitats, large numbers of loci analyzed in an ABC framework enable statistically supported identification of source populations and reconstruction of the direction of inland spread and demographic history following establishment. Information from analyses can direct management actions to limit the spread of invasive species from identified sources and most probable vectors into additional inland aquatic habitats.
Data from: Convergence across a continent: adaptive diversification in a recent radiation of Australian lizards
Recent radiations are important to evolutionary biologists, because they provide an opportunity to study the mechanisms that link micro- and macroevolution. The role of ecological speciation during adaptive radiation has been intensively studied, but radiations can arise from a diversity of evolutionary processes; in particular, on large continental landmasses where allopatric speciation might frequently precede ecological differentiation. It is therefore important to establish a phylogenetic and ecological framework for recent continental-scale radiations that are species-rich and ecologically diverse. Here, we use a genomic (approx. 1 200 loci, exon capture) approach to fit branch lengths on a summary-coalescent species tree and generate a time-calibrated phylogeny for a recent and ecologically diverse radiation of Australian scincid lizards; the genus Cryptoblepharus. We then combine the phylogeny with a comprehensive phenotypic dataset for over 800 individuals across the 26 species, and use comparative methods to test whether habitat specialization can explain current patterns of phenotypic variation in ecologically relevant traits. We find significant differences in morphology between species that occur in distinct environments and convergence in ecomorphology with repeated habitat shifts across the continent. These results suggest that isolated analogous habitats have provided parallel ecological opportunity and have repeatedly promoted adaptive diversification. By contrast, speciation processes within the same habitat have resulted in distinct lineages with relatively limited morphological variation. Overall, our study illustrates how alternative diversification processes might have jointly stimulated species proliferation across the continent and generated a remarkably diverse group of Australian lizards.
Recent hybrids recapitulate ancient hybrid outcomes
<p>Genomic outcomes of hybridization depend on selection and recombination in hybrids. Whether these processes have similar effects on hybrid genome composition in contemporary hybrid zones versus ancient hybrid lineages is unknown. Here we show that patterns of introgression in a contemporary hybrid zone in <em>Lycaeides</em> butterflies predict patterns of ancestry in geographically adjacent, older hybrid populations. We find a particularly striking lack of ancestry from one of the hybridizing taxa, <em>Lycaeides melissa</em>, on the Z chromosome in both the old and contemporary hybrids. The same pattern of reduced <em>L. melissa</em> ancestry on the Z chromosome is seen in two other ancient hybrid lineages. More generally, we find that patterns of ancestry in old or ancient hybrids are remarkably predictable from contemporary hybrids, which suggests selection and recombination affect hybrid genomes in a similar way across disparate time scales and during distinct stages of speciation and species breakdown.</p> <p> </p>
Data from: Recurrent and recent selective sweeps in the piRNA pathway
Uncontrolled transposable element (TE) insertions and excisions can cause chromosome breaks and mutations with dramatic deleterious effects. The PIWI interacting RNA (piRNA) pathway functions as an adaptive TE silencing system during germline development. Several essential piRNA pathway proteins appear to be rapidly evolving, suggesting that TEs and the silencing machinery may be engaged in a classical "evolutionary arms race." Using a variety of molecular evolutionary and population genetic approaches, we find that the piRNA pathway genes rhino, krimper, and aubergine show patterns suggestive of extensive recurrent positive selection across Drosophila species. We speculate that selection on these proteins reflects crucial roles in silencing unfamiliar elements during vertical and horizontal transmission of TEs into naïve populations and species, respectively.
Data from: Formation of a recent hybrid zone offers insight to the geographic puzzle and maintenance of species boundaries in musk turtles
Speciation is the result of an accumulation of reproductive barriers between populations, pinpointing these factors is often difficult. However, hybrid zones can form when these barriers are not complete, especially when lineages come into contact in intermediate or modified habitats. We examine a hybrid zone between two closely related riverine turtle species, Sternotherus depressus and S. peltifer, and use ddRAD sequencing to to understand how this hybrid zone formed and elucidate genomic patterns of reproductive isolation. First the geographic extent and timing of the hybrid zone formation is established to provide context for understanding the role of extrinsic and intrinsic reproductive isolating mechanisms in this system. Then, the strength of selection on taxon-specific contributions to maintenance of the hybrid zone is inferred using a Bayesian genomic cline model. These analyses find a role for selection inhibiting introgression in some genomic regions at one end of the hybrid zone and promoting introgression in many loci at the other. When selective pressures necessary to generate outliers to the genomic cline are considered with the geographic and temporal context of this hybrid zone we conclude that habitat-specific selection likely limits introgression from S. depressus to S. peltifer in the direction of river flow. However, selection is mediating rapid, unidirectional introgression from S. peltifer to S. depressus which is likely facilitated by anthropogenic habitat alteration. These findings indicate a potentially imminent threat of population-level genomic extinction for an already imperiled species due to ongoing human-caused habitat alteration.
Data from: Islands within islands: two montane paleo-endemic birds impacted by recent anthropogenic fragmentation
Anthropogenic habitat fragmentation of species that live in naturally patchy metapopulations such as mountaintops or sky islands experiences two levels of patchiness. Effects of such multilevel patchiness on species have rarely been examined. Metapopulation theory suggests that patchy habitats could have varied impacts on persistence, dependent on differential migration. It is not known whether montane endemic species, evolutionarily adapted to natural patchiness, are able to disperse between anthropogenic fragments at similar spatial scales as natural patches. We investigated historic and contemporary gene flow between natural and anthropogenic patches across the distribution range of a Western Ghats sky-island-endemic bird species complex. Data from 14 microsatellites for 218 individuals detected major genetic structuring by deep valleys, including one hitherto undescribed barrier. As expected, we found strong effects of historic genetic differentiation across natural patches, but not across anthropogenic fragments. Contrastingly, contemporary differentiation (DPS) was higher relative to historic differentiation (FST) in anthropogenic fragments, despite the species' ability to historically traverse shallow valleys. Simulations of recent isolation resulted in high DPS/FST values, confirming recent isolation in Western Ghats anthropogenic fragments and also suggesting that this ratio can be used to identifying recent fragmentation in the context of historic connectedness. We suggest that in this landscape, in addition to natural patchiness affecting population connectivity, anthropogenic fragmentation additionally impacts connectivity, making anthropogenic fragments akin to islands within natural islands of montane habitat, a pattern that may be recovered in other sky-island systems.
Data from: Boom and bust: ancient and recent diversification in bichirs (Polypteridae: Actinopterygii), a relictual lineage of ray-finned fishes
Understanding the history that underlies patterns of species richness across the Tree of Life requires an investigation of the mechanisms that not only generate young species-rich clades, but also those that maintain species-poor lineages over long stretches of evolutionary time. However, diversification dynamics that underlie ancient species-poor lineages are often hidden due to a lack of fossil evidence. Using information from the fossil record and time calibrated molecular phylogenies, we investigate the history of lineage diversification in Polypteridae, which is the sister lineage of all other ray-finned fishes (Actinopterygii). Despite originating at least 390 million years (Myr) ago, molecular timetrees support a Neogene origin for the living polypterid species. Our analyses demonstrate polypterids are exceptionally species depauperate with a stem lineage duration that exceeds 380 million years (Ma) and is significantly longer than the stem lineage durations observed in other ray-finned fish lineages. Analyses of the fossil record show an early Late Cretaceous (100.5–83.6 Ma) peak in polypterid genus richness, followed by 60 Ma of low richness. The Neogene species radiation and evidence for high-diversity intervals in the geological past suggest a "boom and bust" pattern of diversification that contrasts with common perceptions of relative evolutionary stasis in so-called "living fossils."
Data from: Climate-driven build-up of temporal isolation within a recently formed avian hybrid zone
Divergence in the onset of reproduction can act as an important source of reproductive isolation (i.e. allochronic isolation) between co-occurring young species, but evidence for the evolutionary processes leading to such divergence is often indirect. While advancing spring seasons strongly affect the onset of reproduction in many taxa, it remains largely unexplored whether contemporary spring advancement directly affects allochronic isolation between young species. We examined how increasing spring temperatures affected onset of reproduction and thereby hybridization between pied and collared flycatchers (Ficedula spp.) across habitat types in a young secondary contact zone. We found that both species have advanced their timing of breeding in 14 years. However, selection on pied flycatchers to breed earlier was weaker, resulting in a slower response to advancing springs compared to collared flycatchers and thereby build-up of allochronic isolation between the species. We argue that a pre-adaptation to a broader niche use (diet) of pied flycatchers explains the slower response to raising spring temperature, but that reduced risk to hybridize may contribute to further divergence in the onset of breeding in the future. Our results show that minor differences in the response to environmental change of co-occurring closely related species can quickly cause allochronic isolation.
Data from: The herbivorous fish family Kyphosidae (Teleostei: Perciformes) represents a recent radiation from higher latitudes
Aim: Herbivorous reef fishes are considered to have difficulty digesting plant material at extratropical temperatures, and are thus largely restricted to tropical waters where they are thought to have evolved. However, the herbivorous Kyphosidae, with both temperate and tropical species, provides an ideal opportunity to test this view. Previous studies have resolved the taxonomy and distribution patterns of all species. Here, we use a calibrated phylogeny to analyse the age, geographical origin and pattern of diversification of kyphosids to determine their origins in space and time, and thus refine hypotheses on the evolutionary origins of herbivory in reef fishes. Location: Pacific Ocean, Atlantic Ocean, Indian Ocean, Western Australia. Methods: The age and geographic origin of Kyphosidae were determined by incorporating fossil calibrations and species distributions onto a phylogeny of all extant species based on fragments from mitochondrial markers and three nuclear markers, and using Bayesian modelling to reconstruct ancestral distributions. Evolution of both diet and tooth shape were also examined using Bayesian ancestral reconstruction. Results: Ancestral reconstruction suggested a subtropical, southern hemisphere Indo-Pacific origin for the family. The chronogram indicates that Kyphosus originated in the early Miocene, and that tropical diversity reflects very recent diversification. Main conclusions: Contrary to the general perception that herbivorous reef fishes invaded high latitudes from the tropics, herbivorous kyphosids evolved at intermediate latitudes in the southern hemisphere and subsequently diversified into low latitudes where several species dispersed recently to achieve circumglobal distributions. The southern temperate/subtropical reef environment appears to have generated episodes of diversification in several, well-established, widespread reef fish taxa. Some of these reef fish taxa have remained restricted to southern temperate reef environments despite a long tenure in the Cenozoic (e.g. odacines and aplodactylids), and some such as the kyphosids which diversified very recently in both hemispheres resulting in both regional endemics and species with worldwide distributions.
Data from: Insights into VSM diversity and Neoproterozoic biostratigraphy in the light of recent Brazilian discoveries
Vase-shaped microfossils occur in dolostone clasts within conglomerates, breccias and diamictites of the Neoproterozoic Urucum Formation, Jacadigo Group, SW Brazil. Although their taphonomic history is distinct from those of other VSM assemblages, morphometric comparison of Urucum fossils with five others described previously from North America and Europe show that two of the Urucum species --- the long-necked Limeta lageniformis Morais, Fairchild and Lahr, 2017 and the funnel-necked Palaeoamphora urucumense Morais et al., 2017 occur in the Kwagunt and Callison Lake assemblages, as does Pakupaku kabin Riedman, Porter and Calver, 2017 recently described from the Togari Group, Tasmania. Obelix rootsii Cohen, Irvine and Strauss, 2017a (new combination), previously known only from the Callison Lake Formation, is documented here from the Kwagunt Formation. In addition, Trigonocyrillium horodyskii (Bloeser, 1985) and Bonniea dacruchares Porter, Meisterfeld and Knoll 2003, first described from the Kwagunt assemblage, have now been found in the Urucum Formation. In light of this survey, 16 of the 18 validly described VSM species are now known to occur in the Kwagunt Formation and 13 in the Callison Lake Formation, with 12 of them shared by both formations. The fact that the Urucum VSM assemblage exhibits six of seven species in common with the Kwagunt Formation --- L. lageniformis, P. urucumense, Cycliocyrillium simplex Porter et al., 2003, C. torquata Porter et al., 2003, B. dacruchares Porter et al., 2003, and T. horodyskii (Bloeser, 1985) --- and all but the last of these in common with the Callison Lake Formation supports correlation of these three assemblages and indicates that the source of the fossiliferous clasts within the Urucum Formation may well have been a now vanished late Tonian carbonate platform
Data from: Genetic structure of populations of whale sharks among ocean basins and evidence for their historic rise and recent decline
This study presents genetic evidence that whale sharks, Rhincodon typus, are comprised of at least two populations that rarely mix and is the first to document a population expansion. Relatively high genetic structure is found when comparing sharks from the Gulf of Mexico with sharks from the Indo-Pacific. If mixing occurs between the Indian and Atlantic Oceans, it is not sufficient to counter genetic drift. This suggests whale sharks are not all part of a single global meta-population. The significant population expansion we found was indicated by both microsatellite and mitochondrial DNA. The expansion likely happened during the Holocene, when tropical species could expand their range due to sea level rise eliminating dispersal barriers. However, the historic trend of population increase may have reversed recently. Declines in genetic diversity are found for 6 consecutive years at Ningaloo Reef in Australia. The declines in genetic diversity being seen now are likely due to commercial-scale harvesting of whale sharks and collision with boats in past decades in other countries in the Indo-Pacific. Whale shark hunting is banned in Australia but continues in other countries despite bans in places like China. The study findings have implications for models of population connectivity for whale sharks and advocate for continued focus on effective protection of the world's largest fish at multiple spatial scales.
Data from: Recent population decline and selection shape diversity of taxol-related genes
Taxanes are defensive metabolites produced by Taxus species (yews) and used in anticancer therapies. Despite their medical interest, patterns of natural diversity in taxane related genes are unknown. We examined variation at five main taxol-related genes of T. baccata in the Iberian Peninsula, a region where unique yew genetic resources are endangered. We looked at several gene features and applied complementary neutrality tests, including diversity/divergence tests, tests solely based on site-frequency spectrum and Zeng's compound tests. To account for specific demography, microsatellite data were used to infer historical changes in population size based on an Approximate Bayesian Computation (ABC) approach. Polymorphism-divergence tests pointed to positive selection for genes TBT and TAT, and balancing selection for DBAT. In addition, neutrality tests based on site-frequency spectrum found that while a recent reduction in population size may explain most of statistics' values, selection may still be in action in genes TBT and DBAT, at least in some populations. Molecular signatures on taxol genes suggest the action of frequent selective waves with different direction or intensity, possibly related to varying adaptive pressures produced by the host-enemy co-evolution on defense-related genes. Such natural selection processes may have produced taxane variants still undiscovered.
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.