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3,655 results for “Structural data”
Data from: Contact networks structured by sex underpin sex-specific epidemiology of infection
Contact networks are fundamental to the transmission of infection and host sex often affects the acquisition and progression of infection. However, the epidemiological impacts of sex-related variation in animal contact networks have rarely been investigated. We test the hypothesis that sex-biases in infection are related to variation in multilayer contact networks structured by sex in a population of European badgers Meles meles naturally infected with Mycobacterium bovis. Our key results are that male-male and between-sex networks are structured at broader spatial scales than female-female networks and that in male-male and between-sex contact networks, but not female-female networks, there is a significant relationship between infection and contacts with individuals in other groups. These sex differences in social behaviour may underpin male-biased acquisition of infection and may result in males being responsible for more between-group transmission. This highlights the importance of sex-related variation in host behaviour when managing animal diseases.
Data from: Consistent scaling of population structure across landscapes despite intraspecific variation in movement and connectivity
Understanding the spatial scale of population structure is fundamental to long-standing tenets of population biology, landscape ecology and conservation. Nonetheless, identifying such scales has been challenging because a key factor that influences scaling – movement among patches or local populations – is a multicausal process with substantial phenotypic and temporal variation. We resolve this problem via a novel application of network modularity. When applied to movements, modularity provides a formal description of the functional aggregation of populations and identifies potentially critical scales for ecological and evolutionary dynamics. We first test for modularity using several different types of biologically relevant movements across the entire geographic range of an endangered bird, the snail kite (Rostrhamus sociabilis plumbeus). We then ask whether variation in movement based on (i) age, (ii) sex and (iii) time (annual, seasonal and within-season movements) influences spatial population structure (i.e. modularity) in snail kites. We identified significant modularity in annual dispersal of snail kites (all adults, males only, females only, and juveniles only) and in within-breeding season movements of adults, yet no evidence of modularity in seasonal (non-breeding) movements. For those movements with observed modular structure, we found striking similarities in the spatial configuration of population structure, even though movement properties varied considerably among these different types of movements. Our results suggest that the emergence of modularity in population networks can be robust despite movement heterogeneity and differences in patch-based measures of connectivity. Furthermore, our comparison of the population structure and connectivity across multiple movement phases helps to identify wetland patches most critical to population connectivity at multiple spatiotemporal scales. We argue that understanding modularity in populations may provide a robust complement to existing measures of population structure and connectivity and will help to clarify the limiting roles of movement for populations. Such information is increasingly needed for interpreting population persistence and guiding effective conservation strategies with ongoing environmental change.
Data from: Consequences of a poecilogonous life history for genetic structure in coastal populations of the polychaete Streblospio benedicti
In many species, alternative developmental pathways lead to the production of two distinct phenotypes, promoting the evolution of morphological novelty and diversification. Offspring type in marine invertebrates influences transport time by ocean currents, which dictate dispersal potential and gene flow, and thus has sweeping evolutionary effects on the potential for local adaptation and on rates of speciation, extinction, and molecular evolution. Here we use the polychaete Streblospio benedicti to investigate the effects of dimorphic offspring type on gene flow and genetic structure in coastal populations. We use 84 single nucleotide polymorphism (SNP) markers for this species to assay populations on the East and West Coasts of the United States. Using these markers we found that in their native East Coast distribution, populations of S. benedicti have high population genetic structure, but this structure is associated primarily with geographic separation rather than developmental differences. Interestingly, very little genetic differentiation is recovered between individuals of different development types when they occur in the same or nearby populations, further supporting that this is a true case of poecilogony. In addition, we were able to demonstrate that the recently introduced West Coast populations (~100ya) likely originated from a lecithotrophic population near Delaware.
Data from: Contrasting effects of landscape features on genetic structure in different geographical regions in the ornate dragon lizard, Ctenophorus ornatus
Habitat fragmentation can have profound effects on the distribution of genetic variation within and between populations. Previously, we showed that in the ornate dragon lizard, Ctenophorus ornatus, lizards residing on outcrops that are separated by cleared agricultural land are significantly more isolated and hold less genetic variation than lizards residing on neighbouring outcrops connected by undisturbed native vegetation. Here, we extend that fine-scale study to examine the pattern of genetic variation and population structure across the species' range. Using a landscape genetics approach, we test whether land clearing for agricultural purposes has affected the population structure of the ornate dragon lizard. We found significant genetic differentiation between outcrop populations (FST = 0.12), as well as isolation-by-distance within each geographic region. In support of our previous study, land clearing was associated with higher genetic divergences between outcrops and lower genetic variation within outcrops, but only in the region that had been exposed to intense agriculture for the longest period of time. No other landscape features influenced population structure in any geographic region. These results show that the effects of landscape features can vary across species' ranges and suggest there may be a temporal-lag in the response to contemporary changes in land use. These findings therefore highlight the need for caution when assessing the impact of contemporary land use practices on genetic variation and population structure.
Data from: Surviving in mountain climate refugia: new insights from the genetic diversity and structure of the relict shrub Myrtus nivellei (Myrtaceae) in the Sahara desert
The identification of past glacial refugia has become a key topic for conservation under environmental change, since they contribute importantly to shaping current patterns of biodiversity. However, little attention has been paid so far to interglacial refugia despite their key role for the survival of relict species currently occurring in climate refugia. Here, we focus on the genetic consequences of range contraction on the relict populations of the evergreen shrub Myrtus nivellei, endemic in the Saharan mountains since at least the end of the last Green Sahara period, around 5.5 ka B.P. Multilocus genotypes (nuclear microsatellites and AFLP) were obtained from 215 individuals collected from 23 wadis (temporary rivers) in the three main mountain ranges in southern Algeria (the Hoggar, Tassili n'Ajjer and Tassili n'Immidir ranges). Identical genotypes were found in several plants growing far apart within the same wadis, a pattern taken as evidence of clonality. Multivariate analyses and Bayesian clustering revealed that genetic diversity was mainly structured among the mountain ranges, while low isolation by distance was observed within each mountain range. The range contraction induced by the last episode of aridification has likely increased the genetic isolation of the populations of M. nivellei, without greatly affecting the genetic diversity of the species as a whole. The pattern of genetic diversity observed here suggests that high connectivity may have prevailed during humid periods, which is consistent with recent paleoenvironmental reconstructions.
Data from: Fine scale genetic structure among greater sage-grouse leks in central Nevada
Background: Mating systems that reduce dispersal and lead to non-random mating might increase the potential for genetic structure to arise at fine geographic scales. Greater sage-grouse (Centrocercus urophasianus) have a lek-based mating system and exhibit high site fidelity and skewed mating ratios. We quantified population structure by analyzing variation at 27,866 single-nucleotide polymorphisms in 140 males from ten leks (within five lek complexes) occurring in a small geographic region in central Nevada. Results: Lek complexes, and to a lesser extent individual leks, formed statistically identifiable clusters in ordination analyses, providing evidence for fine-scale geographic genetic differentiation. Lek geography predicted genetic differentiation even at a small geographic scale, which could be sharpened by strong site fidelity. Relatedness was also higher among individuals within lek complexes (and leks), suggesting that reproductive skew, where few males participate in most of the successful matings, could also potentially contribute to genetic differentiation. Models incorporating a habitat resistance surface as a proxy for potentially reduced movement due to landscape features indicated that both geographic distance and habitat suitability (i.e. preferred habitat) predicted genetic structure, with no significant effect of man-made barriers to movement (i.e. power lines and roads). Finally, we illustrate how data sets containing fewer loci (<4000) had less statistical precision and failed to detect the full degree of genetic structure. Conclusion: Our results suggest that habitat features and lek site geography of sage-grouse shape fine scale genetic structure, and highlight how larger data sets can have increased precision and accuracy for quantifying ecologically relevant genetic structure over small geographic scales.
Data from: Phylogenetic structural equation modelling reveals no need for an 'origin' of the leaf economics spectrum
The leaf economics spectrum (LES) is a prominent ecophysiological paradigm that describes global variation in leaf physiology across plant ecological strategies using a handful of key traits. Nearly a decade ago, Shipley et al. (2006) used structural equation modelling to explore the causal functional relationships among LES traits that give rise to their strong global covariation. They concluded that an unmeasured trait drives LES covariation, sparking efforts to identify the latent physiological trait underlying the 'origin' of the LES. Here, we use newly developed phylogenetic structural equation modelling approaches to reassess these conclusions using both global LES data as well as data collected across scales in the genus Helianthus. For global LES data, accounting for phylogenetic non-independence indicates that no additional unmeasured traits are required to explain LES covariation. Across datasets in Helianthus, trait relationships are highly variable, indicating that global-scale models may poorly describe LES covariation at non-global scales.
Data from: Landscape genetic analysis suggests stronger effects of past than current landscape structure on genetic patterns of Primula veris
<p>This dataset contains genetic and landscape data of 19 <i>Primula veris</i> populations in Muhu and Saaremaa islands in Estonia. Genetic samples were collected in 2015 and 2016. Landscape data was extracted from maps dated 2016 and 2017 for current data and 1930s for historical data. Data is divided to node- and link-based data. Node-based data contains genetic diversity data of the <i>P. veris</i> populations and landscape data in circular buffers surrounding the populations. Link-based data contains genetic differentiation between population pairs and landscape data in buffers surrounding a straight line between population pairs.</p>
Data from: Flow-ecology relationships are spatially structured and differ among flow regimes
1. In streams, hydrology is a predominant driver of ecological structure and function. Providing adequate flows to support aquatic life, or environmental flows, is therefore a top management priority in stream systems. 2. Flow regime classification is a widely accepted approach for establishing environmental flow guidelines. However, it is surprisingly difficult to quantify relationships between hydrology and ecology (flow-ecology relationships) while describing how these relationships vary across classified flow regimes. Developing such relationships is complicated by several sources of spatial bias, such as autocorrelation due to spatial design, flow regime classification, and other environmental or ecological sources of spatial bias. 3. We used mixed moving-average spatial stream network models to develop flow-ecology relationships across classified flow regimes and to assess spatial patterns of these relationships. We compared relationships between fish traits and life-history strategies with hydrologic metrics across flow regimes and assessed whether spatial autocorrelation influenced these relationships. 4. Trait-hydrology relationships varied between flow regimes and across all streams combined. Some relationships between traits and hydrologic metrics fit predictions based on life-history theory, while others exhibited unexpected relationships with hydrology. Spatial factors described a large proportion of variability in fish traits and different patterns of spatial autocorrelation were observed in different flow regimes. Synthesis and Applications. Further work is needed to understand why flow-ecology relationships vary across classified flow regimes and why these relationships may not fit predictions based on life-history theories. Managers determining environmental flow standards need to be aware that different hydrologic metrics are often important drivers of fish trait diversity in different flow-regimes. Flow-ecology relationships may therefore be confounded by spatial structure that is inherent in flow regime classification and much existing biological data. Complex patterns of spatial bias should be considered when managing stream systems within an environmental flows framework.
Data from: Species-driven phases and increasing structure in early-successional plant communities
Successional phases describe changes in ecological communities that proceed in steps rather than continuously. Despite their importance for the understanding of ecosystem development, there still exists no reliable definition of phases and no quantitative measure of phase transitions. In order to obtain these data, we investigated primary succession in an artificial catchment (6 ha) in eastern Germany over a period of 6 years. The data set consists of records of plant species and their cover values, and initial substrate properties, both from plots in a regular grid (20 m × 20 m) suitable for spatial data analysis. Community assembly was studied by analyses of species co-occurrence and nestedness. Additionally, we correlated lognormal and log series distributions of species abundance to each community. We here introduce a new general method for detection of successional phases based on the degree of transient spatial homogeneity in the study system. Spatially coherent vegetation patterns revealed nonoverlapping partitions within this sequence of primary succession and were characterized as two distinct ecological phases. Patterns of species co-occurrence were increasingly less random, and hence the importance of demographic stochasticity and neutral community assembly decreased during the study period. Our findings highlight the spatial dimension of successional phases and quantify the degree of change between these steps. They are an element for advancing a more reliable terminology of ecological successions.
Data from: The role of structural genomic variants in population differentiation and ecotype formation in Timema cristinae walking sticks
Theory predicts that structural genomic variants such as inversions can promote adaptive diversification and speciation. Despite increasing empirical evidence that adaptive divergence can be triggered by one or a few large inversions, the degree to which widespread genomic regions under divergent selection are associated with structural variants remains unclear. Here we test for an association between structural variants and genomic regions that underlie parallel host-plant associated ecotype formation in Timema cristinae stick insects. Using mate-pair re-sequencing of 20 new whole genomes we find that modest-sized structural variants such as inversions, deletions, and duplications are widespread across the genome, being retained as standing variation within and among populations. Using 160 previously published, standard-orientation whole genome sequences we find little to no evidence that the DNA sequences within inversions exhibit accentuated differentiation between ecotypes. In contrast, a formerly described large region of reduced recombination that harbors genes controlling color-pattern exhibits evidence for accentuated differentiation between ecotypes, which is consistent with differences in the frequency of color-pattern morphs between host-associated ecotypes. Our results suggest that some types of structural variants (e.g., large inversions) are more likely to underlie adaptive divergence than others, and that structural variants are not required for subtle yet genome-wide genetic differentiation with gene flow.
Data from: Geographic extent of introgression in Sebastes mentella and its effect on genetic population structure
Genetic population structure is often used to identify management units in exploited species, but the extent of genetic differentiation may be inflated by geographic variation in the level of hybridization between species. We identify the genetic population structure of Sebastes mentella and investigate possible introgression within the genus by analyzing 13 microsatellites in 2,562 redfish specimens sampled throughout the North Atlantic. The data support an historical divergence between the "shallow" and "deep" groups, beyond the Irminger Sea where they were described previously. A third group, "slope," has an extended distribution on the East Greenland Shelf, in addition to earlier findings on the Icelandic slope. Furthermore, S. mentella from the Northeast Arctic and Northwest Atlantic waters are genetically different populations. In both areas, interspecific introgression may influence allele frequency differences among populations. Evidence of introgression was found for almost all the identified Sebastes gene pools, but to a much lower extent than suggested earlier. Greenland waters appear to be a sympatric zone for many of the genetically independent Sebastes groups. This study illustrates that the identified groups maintain their genetic integrity in this region despite introgression.
Data from: Unexpected population genetic structure of European roe deer in Poland: an invasion of the mtDNA genome from Siberian roe deer
Introgressive hybridization is a widespread evolutionary phenomenon which may lead to increased allelic variation at selective-neutral loci and to transfer of fitness-related traits to introgressed lineages. We inferred the population genetic structure of the European roe deer (Capreolus capreolus) in Poland from mitochondrial (CR and cyt b) and sex-linked markers (ZFX, SRY, DBY4 and DBY8). Analyses of CR mtDNA sequences from 452 individuals indicated widespread introgression of Siberian roe deer (C. pygargus) mtDNA in the European roe deer genome, 2000 km from the current distribution range of C. pygargus. Introgressed individuals constituted 16.6% of the deer studied. Nearly 75% of them possessed haplotypes belonging to the group which arose 23 kyr ago and have not been detected within the natural range of Siberian roe deer, indicating that majority of present introgression has ancient origin. Unlike the mtDNA results, sex-specific markers did not show signs of introgression. Species distribution modelling analyses suggested that C. pygargus could have extended its range as far west as Central Europe after LGM. The main hybridization event was probably associated with range expansion of the most abundant European roe deer lineage from western refugia and took place in Central Europe after the Younger Dryas (10.8–10.0 ka BP). Initially introgressed mtDNA variants could have spread out on the wave of expansion through the mechanism of gene surfing, reaching high frequencies in European roe deer populations and leading to observed asymmetrical gene flow. Human-mediated introductions of C. pygargus had minimal effect on the extent of mtDNA introgression.
Data from: Genetic structure of fragmented southern populations of African Cape buffalo (Syncerus caffer caffer)
Background: African wildlife experienced a reduction in population size and geographical distribution over the last millennium, particularly since the 19th century as a result of human demographic expansion, wildlife overexploitation, habitat degradation and cattle-borne diseases. In many areas, ungulate populations are now largely confined within a network of loosely connected protected areas. These metapopulations face gene flow restriction and run the risk of genetic diversity erosion. In this context, we assessed the "genetic health" of free ranging southern African Cape buffalo populations (S.c. caffer) and investigated the origins of their current genetic structure. The analyses were based on 264 samples from 6 southern African countries that were genotyped for 14 autosomal and 3 Y-chromosomal microsatellites. Results: The analyses differentiated three significant genetic clusters, hereafter referred to as Northern (N), Central (C) and Southern (S) clusters. The results suggest that splitting of the N and C clusters occurred around 6000 to 8400 years ago. Both N and C clusters displayed high genetic diversity (mean allelic richness (Ar) of 7.217, average genetic diversity over loci of 0.594, mean private alleles (Pa) of 11), low differentiation, and an absence of an inbreeding depression signal (mean FIS = 0.037). The third (S) cluster, a tiny population enclosed within a small isolated protected area, likely originated from a more recent isolation and experienced genetic drift (FIS = 0.062, mean Ar = 6.160, Pa = 2). This study also highlighted the impact of translocations between clusters on the genetic structure of several African buffalo populations. Lower differentiation estimates were observed between C and N sampling localities that experienced translocation over the last century. Conclusions: We showed that the current genetic structure of southern African Cape buffalo populations results from both ancient and recent processes. The splitting time of N and C clusters suggests that the current pattern results from human-induced factors and/or from the aridification process that occurred during the Holocene period. The more recent S cluster genetic drift probably results of processes that occurred over the last centuries (habitat fragmentation, diseases). Management practices of African buffalo populations should consider the micro-evolutionary changes highlighted in the present study.
Data from: Technical note: rapid image-based field methods improve the quantification of termite mound structures and greenhouse-gas fluxes
Termite mounds (TMs) mediate biogeochemical processes with global relevance, such as turnover of the important greenhouse gas methane (CH4). However, the complex internal and external morphology of TMs impede an accurate quantitative description. Here we present two novel field methods, photogrammetry (PG) and cross-section image analysis, to quantify TM external and internal mound structure of 29 TMs of three termite species. Photogrammetry was used to measure epigeal volume (VE), surface area (AE) and mound basal area (AB) by reconstructing 3D models from digital photographs, and compared against a water-displacement method and the conventional approach of approximating TMs by simple geometric shapes. To describe TM internal structure, we introduce TM macro- and micro-porosity (θM and θµ), the volume fractions of macroscopic chambers, and microscopic pores in the wall material, respectively. Macro-porosity was estimated using image analysis of single TM cross-sections, and compared against full x-ray tomography (CT) scans of 17 TMs. For these TMs we present complete pore fractions to assess species-specific differences in internal structure. The PG method yielded VE nearly identical to a water-displacement method, while approximation of TMs by simple geometric shapes led to errors of 4–200 %. Likewise, using PG substantially improved the accuracy of CH4 emission estimates by 10–50 %. Comprehensive CT scanning revealed that investigated TMs have species-specific ranges of θM and θµ, but similar total porosity. Image analysis of single TM cross-sections produced good estimates of θM for species with thick walls and evenly distributed chambers. The new image-based methods allow rapid and accurate quantitative characterisation of TMs to answer ecological, physiological and biogeochemical questions. The PG method should be applied when measuring greenhouse-gas emissions from TMs to avoid large errors from inadequate shape approximations.
Data from: Building genetic networks using relatedness information: a novel approach for the estimation of dispersal and characterization of group structure in social animals
Natal dispersal is an important life history trait driving variation in individual fitness and, therefore, a proper understanding of the factors underlying dispersal behaviour is critical to many fields including population dynamics, behavioural ecology and conservation biology. However, individual dispersal patterns remain difficult to quantify despite many years of research using direct and indirect methods. Here, we quantify dispersal in a single intensively-studied population of the cooperatively breeding chestnut-crowned babbler (Pomatostomus ruficeps) using genetic networks created from the combination of pairwise relatedness data and social networking methods and compare this to dispersal estimates from re-sighting data. Not only does this novel approach identify movements between social groups within our study sites but also provides an estimation of immigration rates of individuals originating outside the study site. Both genetic and re-sighting data indicated that dispersal was strongly female-biased, but the magnitude of dispersal estimates was much greater using genetic data. This suggests that many previous studies relying on mark-recapture data may have significantly underestimated dispersal. An analysis of spatial genetic structure within the sampled population also supports the idea that females are more dispersive, with females having no structure beyond the bounds of their own social group while male genetic structure expands for 750 meters from their social group. Although the genetic network approach we have used is an excellent tool for visualising the social and genetic microstructure of social animals and identifying dispersers, our results also indicate the importance of applying them in parallel with behavioural and life history data.
Data from: Social structure of the harem-forming promiscuous fruit bat, Cynopterus sphinx, is the harem truly important?
Bats are social animals and display a diverse variety of mating and social systems, with most species exhibiting some form of polygyny. Their social organization is fluid and individuals frequently switch partners and roosting sites. While harem-like social organization is observed in multiple tropical species, its importance is contested in many of them. In this study, we investigated the role of harems in the social organization of the old world fruit bat Cynopterus sphinx. Based on regular behavioural observations over a period of 20 months and genetic data from microsatellite markers, we observed that the social organization is flexible, individuals regularly shift between roosts and the social organization resembles a fission–fusion society. Behavioural and genetic analyses suggest that the harems are not strict units of social structure, and the colony does not show signatures of subdivision with harems as behavioural units. We also observed that there was no correlation between individuals with high association index and pairwise relatedness. Our findings indicate that similar to the mating system, the social organization of C. sphinx can also be categorized as a fission–fusion society, and hence the term 'harem' is a misnomer. We conclude that the social system of C. sphinx is flexible, with multi-male multi-female organization, and individuals tend to be loyal to a given area rather than a roost.
Data from: Landscape models for nuclear genetic diversity and genetic structure in white-footed mice (Peromyscus leucopus)
Dramatic changes in the North American landscape over the last 12 000 years have shaped the genomes of the small mammals, such as the white-footed mouse (Peromyscus leucopus), which currently inhabit the region. However, very recent interactions of populations with each other and the environment are expected to leave the most pronounced signature on rapidly evolving nuclear microsatellite loci. We analyzed landscape characteristics and microsatellite markers of P. leucopus populations along a transect from southern Ohio to northern Michigan, in order to evaluate hypotheses about the spatial distribution of genetic heterogeneity. Genetic diversity increased to the north and was best approximated by a single-variable model based on habitat availability within a 0.5-km radius of trapping sites. Interpopulation differentiation measured by clustering analysis was highly variable and not significantly related to latitude or habitat availability. Interpopulation differentiation measured as FST values and chord distance was correlated with the proportion of habitat intervening, but was best explained by agricultural distance and by latitude. The observed gradients in diversity and interpopulation differentiation were consistent with recent habitat availability being the major constraint on effective population size in this system, and contradicted the predictions of both the postglacial expansion and core-periphery hypotheses.
Data from: Population structure and history of the Welsh sheep breeds determined by whole genome genotyping
Background: One of the most economically important areas within the Welsh agricultural sector is sheep farming, contributing around £230 million to the UK economy annually. Phenotypic selection over several centuries has generated a number of native sheep breeds, which are presumably adapted to the diverse and challenging landscape of Wales. Little is known about the history, genetic diversity and relationships of these breeds with other European breeds. We genotyped 353 individuals from 18 native Welsh sheep breeds using the Illumina OvineSNP50 array and characterised the genetic structure of these breeds. Our genotyping data were then combined with, and compared to, those from a set of 74 worldwide breeds, previously collected during the International Sheep Genome Consortium HapMap project. Results: Model based clustering of the Welsh and European breeds indicated shared ancestry. This finding was supported by multidimensional scaling analysis (MDS), which revealed separation of the European, African and Asian breeds. As expected, the commercial Texel and Merino breeds appeared to have extensive co-ancestry with most European breeds. Consistently high levels of haplotype sharing were observed between native Welsh and other European breeds. The Welsh breeds did not, however, form a genetically homogeneous group, with pairwise FST between breeds averaging 0.107 and ranging between 0.020 and 0.201. Four subpopulations were identified within the 18 native breeds, with high homogeneity observed amongst the majority of mountain breeds. Recent effective population sizes estimated from linkage disequilibrium ranged from 88 to 825. Conclusions: Welsh breeds are highly diverse with low to moderate effective population sizes and form at least four distinct genetic groups. Our data suggest common ancestry between the native Welsh and European breeds. These findings provide the basis for future genome-wide association studies and a first step towards developing genomics assisted breeding strategies in the UK.
Data from: Size structuring and allometric scaling relationships in coral reef fishes
Temperate marine fish communities are often size structured, with predators consuming increasingly larger prey and feeding at higher trophic levels as they grow. Gape limitation and ontogenetic diet shifts are key mechanisms by which size structuring arises in these communities. Little is known, however, about size structuring in coral reef fishes. Here, we aimed to advance understanding of size structuring in coral reef food webs by examining the evidence for these mechanisms in two groups of reef predators. Given the diversity of feeding modes amongst coral reef fishes, we also compared gape size—body size allometric relationships across functional groups to determine if they are reliable indicators of size structuring. We used gut content analysis and quantile regressions of predator size—prey size relationships to test for evidence of gape limitation and ontogenetic niche shifts in reef piscivores (n=13 species) and benthic invertivores (n=3 species). We then estimated gape size—body size allometric scaling coefficients for 21 different species from four functional groups, including herbivores/detritivores, which are not expected to be gape-limited. We found evidence of both mechanisms for size structuring in coral reef piscivores, with maximum prey size scaling positively with predator body size, and ontogenetic diet shifts including prey type and expansion of prey size. There was, however, little evidence of size structuring in benthic invertivores. Across species and functional groups, absolute and relative gape sizes were largest in piscivores as expected, but gape size—body size scaling relationships were not indicative of size structuring. Instead, relative gape sizes and mouth morphologies may be better indicators. Our results provide evidence that coral reef piscivores are size-structured, and that gape limitation and ontogenetic niche shifts are the mechanisms from which this structure arises. Although gape allometry was not indicative of size structuring, it may have implications for ecosystem function: positively allometric gape size—body size scaling relationships in herbivores/detritivores suggests that loss of large-bodied individuals of these species will have a disproportionately negative impact on reef grazing pressure.
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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.