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.
2,911
datasets available to search
ShareScore release 0.7.1
Dataset results
2,911 results for “dispersal”
Data from: Behavioral vs. molecular sources of conflict between nuclear and mitochondrial DNA: the role of male-biased dispersal in a Holarctic sea duck
Genetic studies of waterfowl (Anatidae) have observed the full spectrum of mitochondrial (mt) DNA population divergence, from panmixia to deep, reciprocally monophyletic lineages. Yet these studies generally found weak or no nuclear (nu) DNA structure which was often attributed to sex-biased gene flow (i.e., male dispersal and female philopatry), a common behavior within this family. An alternative explanation for this "conflict" is that the smaller effective population size and faster sorting rate of mtDNA relative to nuDNA leads to different signals of population structure. To test these alternatives, we simulated expected nuDNA differentiation based on mtDNA patterns of effective population sizes, gene flow, and divergence times in a Holarctic pair of waterfowl subspecies, the goosander (Mergus merganser merganser) and common merganser (M. m. americanus). We compared simulated results to empirical data from 12 nuDNA introns sampled from the species' global range. Between Europe and North America, nuDNA ФST was 3.4-fold lower than mtDNA ФST, a result consistent with differences in sorting rates. However, despite geographically structured and monophyletic mtDNA lineages within continents, nuDNA ФST values were generally < 0 and significantly lower than predicted. This between- and within-continent contrast held when comparing mtDNA and nuDNA among published studies of ducks. Thus, male-mediated gene flow is a better explanation than slower sorting rates for limited nuDNA differentiation within continents, which is also supported by non-molecular data. This study illustrates the value of quantitatively testing discrepancies between mtDNA and nuDNA to reject the null hypothesis that conflict simply reflects different sorting rates.
How far do Asian hornbills disperse seeds?
<p>Biotic seed dispersal of plants is a complex phenomenon that is influenced by multiple seed disperser species with implications for plant fitness and range expansions. While inter-species variation has been well-studied, the importance of incorporating intraspecific variation in seed dispersal is increasingly being acknowledged. We compared seed dispersal patterns of breeding and non-breeding great hornbills <i>Buceros bicornis</i> and a breeding wreathed hornbill <i>Rhyticeros undulatus</i> by combining data on fruiting tree visitations, gut passage time and movement data from tagged hornbills. Seed dispersal probability at nest trees (by breeding males) was low (< 12%) suggesting that males scatter-disperse seeds, unlike breeding females that deposit seeds below nest trees. Median seed dispersal distance of great hornbills was 294 m and 254 m in the breeding and non-breeding season respectively, and, the distribution tail was shorter for breeding birds (2.5 km) than non-breeding birds (13 km). The median and maximum seed dispersal distance by the wreathed hornbill was 1.35 km and 11 km respectively. This study highlights intraspecific variation in seed dispersal patterns across sexes and breeding and non-breeding male hornbills and potential variation between two hornbill species. This is the first study that estimates long-distance seed dispersal by Asian hornbills. </p>
Data from: High connectivity across the fragmented chemosynthetic ecosystems of the deep Atlantic Equatorial Belt: efficient dispersal mechanisms or questionable endemism?
Chemosynthetic ecosystems are distributed worldwide in fragmented habitats harbouring seemingly highly specialized communities. Yet, shared taxa have been reported from highly distant chemosynthetic communities. These habitats are distributed in distinct biogeographical regions, one of these being the so-called Atlantic Equatorial Belt (AEB). Here, we combined genetic data (COI) from several taxa to assess the possible existence of cryptic or synonymous species and to detect the possible occurrence of contemporary gene flow among populations of chemosynthetic species located on both sides of the Atlantic. Several Evolutionary Significant Units (ESUs) of Alvinocarididae shrimp and Vesicomyidae bivalves were found to be shared across seeps of the AEB. Some were also common to hydrothermal vent communities of the Mid-Atlantic Ridge (MAR), encompassing taxa morphologically described as distinct species or even genera. The hypothesis of current or very recent large-scale gene flow among seeps and vents was supported by microsatellite analysis of the shrimp species Alvinocaris muricola/Alvinocaris markensis across the AEB and MAR. Two nonmutually exclusive hypotheses may explain these findings. The dispersion of larvae or adults following strong deep-sea currents, possibly combined with biochemical cues influencing the duration of larval development and timing of metamorphosis, may result in large-scale effective migration among distant spots scattered on the oceanic seafloor. Alternatively, these results may arise from the prevailing lack of knowledge on the ocean seabed, apart from emblematic ecosystems (chemosynthetic ecosystems, coral reefs or seamounts), where the widespread classification of endemism associated with many chemosynthetic taxa might hide wider distributions in overlooked parts of the deep sea.
Data from: Homogenization of dispersal ability across bird species in response to landscape change
Human land use is known to homogenize biotic communities, increasing similarity in their genetic, taxonomic and functional diversity. Explanations have focused almost exclusively on human-mediated extinction and range expansion. However, homogenization could also be produced by land use driving selection for similar traits across species. We propose a novel hypothesis to explain how human land use homogenizes dispersal ability across species. With habitat loss and increasing human land use intensities there should be larger increases in the costs of dispersal for dispersive than sedentary species, because dispersive species interact with non-habitat more frequently. In contrast, the benefits of dispersal should increase more for sedentary than dispersive species, because sedentary species are at greater risk from inbreeding depression, predation and competition associated with habitat loss. Therefore we predict that sedentary species become more dispersive in a human-altered landscape, and dispersive species more sedentary. We tested this prediction using wing pointedness to estimate the initial dispersal ability and change in dispersal ability for 21 North American passerines over the 20th century. More pointed wings are associated with stronger dispersal ability. Thus our prediction would be supported by a negative cross-species relationship between these two measurements. We found a strong, negative relationship, as predicted. This resulted in declines in the variability in wing pointedness among species over time. Although other things can cause wing shape to change, including changes in habitat availability, none of these explained the observed relationship. Our result provides the first evidence that human landscape alteration is homogenizing bird communities, driving selection for intermediate dispersal ability across species. It also implies that more dispersive species are more at-risk from human landscape use because, when rates of landscape alteration are faster than a species' ability to adapt to that change, the costs of dispersal increase more for dispersive than sedentary species.
Data from: Chemical tradeoffs in seed dispersal: Defensive metabolites in fruits deter consumption by mutualist bats
Although fleshy fruits function primarily to attract seed dispersers, many animal-dispersed fruits contain potentially toxic secondary metabolites. These metabolites can provide defense against seed predators and pathogens, but their effects on dispersers are still poorly understood. In some cases plants may experience a tradeoff, where the metabolites that provide fruit defense also reduce seed disperser preferences. In other cases the bioactivity of fruit secondary metabolites may be directed primarily at pests with no negative effects on seed-dispersing vertebrates. We tested the effects of amides, a group of nitrogen-based defensive compounds common in the plant genus Piper (Piperaceae), in interactions with the primary seed dispersers of Piper in the neotropics – fruit-feeding bats in the genus Carollia (Phyllostomidae). In a series of flight cage experiments, pure amides and amide-rich fruit extracts reduced the preferences of bats for Piper fruit, affecting both the bats' initial choices to remove Piper infructescences and the proportion of fruit consumed from individual infructescences once they were removed. However, the effects of amides varied considerably among three species of Carollia and among the specific individual amides and extracts tested. Overall, our results support the hypothesis that plants experience a tradeoff between seed dispersal and fruit defense, but the strength of this tradeoff and the overall fitness consequences may depend strongly on ecological context.
Data from: At least some meiofaunal species are not everywhere. Indication of geographic, ecological and geological barriers affecting the dispersion of species of Ototyphlonemertes (Nemertea, Hoplonemertea)
Most meiofaunal species are known to have a broad distribution with no apparent barriers to their dispersion. However, different morphological and/or molecular methods supported patterns of diversity and distribution that may be different among taxa while also conflicting within the same group. We accurately assessed the patterns of geographic distribution in actual genetic species of a marine meiofaunal animal model: Ototyphlonemertes. Specimens were collected from several sites around Europe, Northern and Central America, Southern America, Pacific Islands and Asia. We sequenced regions of two mitochondrial and two nuclear genes. Using single-gene, a concatenated data set, multilocus approaches and different DNA taxonomy methods, we disentangled the actual diversity and the spatial structures of haplotypes and tested the possible correlation between genetic diversity and geographic distance. The results show (i) the importance of using several genes to uncover both diversity and highlight phylogeographic relationships among species and that (ii) independent genetic evolutionary entities have a narrower distribution than morphological species. Moreover, (iii) a Mantel test supported a positive correlation between genetic and geographical distance. By sampling from the two sides of Isthmus of Panama, we were additionally able to identify lineage divergence times that are concordant with vicariance mechanisms caused by the geological closure of the seaway across the Isthmus. We therefore propose that in addition to distance, other geological and ecological conditions are also barriers to the dispersion of and gene flow in marine meiofaunal organisms.
Data from: Quantification of within- and between-farm dispersal of Culicoides biting midges using an immunomarking technique
Culicoides biting midges (Diptera, Ceratopogonidae) are vectors of arboviruses that cause significant economic and welfare impact. Local-scale spread of Culicoides-borne arboviruses is largely determined by the between-farm movement of infected Culicoides. Study of the dispersal behaviour of Culicoides by capture–mark–recapture (CMR) is problematic due to the likelihood of mortality and changes in behaviour upon capture caused by the small size and fragility of these insects, evidenced by low recapture rates. To counter the problem of using CMR with Culicoides, this study utilised an ovalbumin immunomarking technique to quantify the within- and between-farm dispersal of Culicoides in southern England. Both within- and between-farm dispersal of Culicoides was observed. Of the 9058 Culicoides collected over 22 nights of trapping, 600 ovalbumin-positive Culicoides, of 12 species including those implicated as arbovirus vectors, were collected with a maximum dispersal distance of 3125 m. This study provides the first species-level data on the between-farm dispersal of potential bluetongue, Schmallenberg and African horse sickness virus vectors in northern Europe. High-resolution meteorological data determined upwind and downwind flight by Culicoides had occurred. Cumulative collection and meteorological data suggest 15·6% of flights over 1 km were upwind of the treatment area and 84·4% downwind. Synthesis and applications. The use of immunomarking eliminates the potential adverse effects on survival and behaviour of insect collection prior to marking, substantially improving the resolution and accuracy of estimates of the dispersal potential of small and delicate vector species such as Culicoides. Using this technique, quantification of the range of Culicoides dispersal with regard to meteorological conditions including wind direction will enable improved, data-driven modelling of the spread of Culicoides-borne arboviruses and will inform policy response to incursions and outbreaks.
Data from: Rapid increase in dispersal during range expansion in the invasive ladybird Harmonia axyridis
The evolutionary trajectories associated with demographic, genetic and spatial disequilibrium have become an issue of growing interest in population biology. Invasive species provide unique opportunities to explore the impact of recent range expansion on life-history traits, making it possible to test for a spatial arrangement of dispersal abilities along the expanding range, in particular. We carried out controlled experiments in laboratory conditions to test the hypothesis of an increase in dispersal capacity with range expansion in Harmonia axyridis, a ladybird that has been invading Europe since 2001. We found a marked increase in the flight speed of the insects from the core to the front of the invasion range in two independent sampling transects. By contrast, we found that two other traits associated with dispersal (endurance and motivation to fly off) did not follow the same spatial gradient. Our results provide a striking illustration of the way in which predictable directional genetic changes may occur rapidly for some traits associated with dispersal during biological invasions. We discuss the consequences of our results for invasion dynamics and the evolutionary outcomes of spatially expanding populations.
Data from: Effects of dispersal mode on the environmental and spatial correlates of nestedness and species turnover in pond communities
Advances in metacommunity theory have made a significant contribution to understanding the drivers of variation in biological communities. However, there has been limited empirical research exploring the expression of metacommunity theory for two fundamental components of beta diversity: nestedness and species turnover. In this paper, we examine the influence of local environmental and a range of spatial variables (hydrological connectivity, proximity and overall spatial structure) on total beta diversity and the nestedness and turnover components of beta diversity for the entire macroinvertebrate community and active and passively dispersing taxa within pond habitats. High beta diversity almost entirely reflects patterns of species turnover (replacement) rather than nestedness (differences in species richness) in our dataset. Local environmental variables were the main drivers of total beta diversity, nestedness and turnover when the entire community was considered and for both active and passively dispersing taxa. The influence of spatial processes on passively dispersing composition, total beta diversity and nestedness was significantly greater than for actively dispersing taxa. Our results suggest that species sorting (local environmental variables) operating through niche processes was the primary mechanism driving total beta diversity, nestedness and turnover for the entire community and active and passively dispersing taxa. In contrast, spatial factors (hydrological connectivity, proximity and spatial eigenvectors) only exerted a secondary influence on the nestedness and turnover components of beta diversity.
Data from: Demography-dispersal trait correlations modify the eco-evolutionary dynamics of range expansion
Spreading populations are subject to evolutionary processes acting on dispersal and reproduction that can increase invasion speed and variability. It is typically assumed that dispersal and demography traits evolve independently, but abundant evidence points to correlations between them that may be positive or negative, genetic or environmental. We sought to understand how demography-dispersal correlations modify the eco-evolutionary dynamics of range expansion. We first explored this question with the beetle Callosobruchus maculatus, a laboratory model in which evolutionary acceleration of invasion has been demonstrated. We then built a simulation model to explore the role of trait correlations in this system and more generally. We found that positive correlations amplify the positive influence of evolution on speed and variability, while negative correlations (such as we found empirically) constrain that influence. Strong negative genetic correlations can even cause evolution to decelerate invasion. Heritable and environmental correlations had similar effects on some measures of invasion but different effects on others. Model results enabled us to retrospectively explain invasion dynamics and trait evolution in C. maculatus, and may similarly aid the interpretation of other field and laboratory studies. Non-independence of demography and dispersal is an important consideration for understanding and predicting outcomes of range expansion.
Data from: Multi-scale effects of habitat structure and landscape context on a vertebrate with limited dispersal ability (the brown-throated sloth, Bradypus variegatus)
As human population, food consumption, and demand for forest products continue to rise over the next century, the pressures of land use change on biodiversity are projected to intensify. In tropical regions, countryside habitats that retain abundant tree cover and structurally complex canopies may complement protected areas by providing suitable habitats and landscape connectivity for a significant portion of the native biota. Species with low dispersal capabilities are among the most at risk of extinction as a consequence of land use change. We assessed how the spatial distribution of the brown-throated sloth (Bradypus variegatus), a model species for a vertebrate with limited dispersal ability, is shaped by differences in habitat structure and landscape patterns of countryside habitats in north-central Costa Rica using a multi-scale framework. We quantified the influence of local habitat characteristics and landscape context on sloth occurrence using mixed-effects logistic regression models. We recorded 27 sloths within countryside habitats and found that both local and landscape factors significantly influenced their spatial distribution. Locally, sloths favored structurally complex habitats, with greater canopy cover and variation in tree height and basal area. At the landscape scale, sloths demonstrated a preference for habitats with high proportions of forest and nearly large tracts of forest. Although mixed-use areas and tree plantations are not substitutes for protected forests, our results suggest they provide important supplemental habitats for sloths. To promote the conservation and long-term viability of sloth populations in the tropical countryside, we recommend for land managers to retain structurally complex vegetation and large patches of native habitat.
Data from: Dispersal to or from an African biodiversity hotspot?
Biodiversity hotspots are centers of endemism and thus contain many range-restricted species. In addition, within these hotspots are often widespread species that might have originated within a hotspot before dispersing to neighboring or distant regions. We test this hypothesis through a phylogeographic analysis of a miniature leaf litter frog, Arthroleptis xenodactyloides, that has a large distribution throughout the Eastern Arc, a biodiversity hotspot, and other regions in East Africa. Maximum likelihood and Bayesian estimates of the mitochondrial gene phylogeny are used as a proxy for understanding the evolutionary history of diversification and the historical relationships between populations. The north-south range of this species extends for approximately 1900 km; our sampling covers approximately 85% of this range. Using phylogenetic comparative methods, we estimate the region of origin and direction of dispersal within A. xenodactyloides. We compare contrasting hypotheses of latitudinal range expansion using bayes factors. The ancestral region of origin of A. xenodactyloides is reconstructed as having occurred within the Eastern Arc before dispersing southwards into the Southern Rift mountains, probably in the Pleistocene. The phylogeographic structure within this leaf litter frog is surprisingly similar to that of forest birds, revealing that similar geographic features might have had a driving role in diversification of these very dissimilar taxa. Latitudinal expansion occurred early in the evolutionary history of A. xenodactyloides and may indicate that physiological adaptation facilitated its wide geographic distribution.
Data from: Colonisation dynamics during range expansion is poorly predicted by dispersal in the core range
The potential ranges of many species are shifting due to changing ecological conditions. Where populations become patchy towards the range edge, the realised distribution emerges from colonisation-persistence dynamics. Therefore, a greater understanding of the drivers of these processes, and the spatial scales over which they operate, presents an opportunity to improve predictions of species range expansion under environmental change. Species reintroductions offer an ideal opportunity to investigate the drivers and spatial scale of colonisation dynamics at the range edge. To this effect, we performed and monitored experimental translocations of water voles to quantify how colonisation and local persistence were influenced by habitat quality and occupancy. We used a novel statistical method to simultaneously consider effects across a range of spatial scales. Densely occupied neighbourhoods were highly persistent and frequently colonised. Persistence was more likely in high quality habitat, whereas influence of habitat quality on colonisation was less clear. Colonisation of suitable habitat in distant, sparsely occupied areas was much less frequent than expected from the well documented high dispersal ability of the species. Persistence of these distant populations was also low, which we attribute to the absence of a rescue effect in sparsely populated neighbourhoods. Our results illustrate a mismatch between the spatial scales of colonisation dynamics in the core and edge of a species range, suggesting that recolonisation dynamics in established populations may be a poor predictor of colonisation dynamics at the range edge. Such a mismatch leads to predictions of long lags between the emergence and colonisation of new habitat, with detrimental consequences for a species realised distribution, conservation status and contribution to ecosystem function. Conservation translocations that also reinforce existing populations at the range edge might stimulate the rescue effect and mitigate lags in expansion.
Data from: Combined genetic and telemetry data reveal high rates of gene flow, migration, and long-distance dispersal potential in Arctic ringed seals (Pusa hispida)
Ringed seals (Pusa hispida) are broadly distributed in seasonally ice covered seas, and their survival and reproductive success is intricately linked to sea ice and snow. Climatic warming is diminishing Arctic snow and sea ice and threatens to endanger ringed seals in the foreseeable future. We investigated the population structure and connectedness within and among three subspecies: Arctic (P. hispida hispida), Baltic (P. hispida botnica), and Lake Saimaa (P. hispida saimensis) ringed seals to assess their capacity to respond to rapid environmental changes. We consider (a) the geographical scale of migration, (b) use of sea ice, and (c) the amount of gene flow between subspecies. Seasonal movements and use of sea ice were determined for 27 seals tracked via satellite telemetry. Additionally, population genetic analyses were conducted using 354 seals representative of each subspecies and 11 breeding sites. Genetic analyses included sequences from two mitochondrial regions and genotypes of 9 microsatellite loci. We found that ringed seals disperse on a pan-Arctic scale and both males and females may migrate long distances during the summer months when sea ice extent is minimal. Gene flow among Arctic breeding sites and between the Arctic and the Baltic Sea subspecies was high; these two subspecies are interconnected as are breeding sites within the Arctic subspecies.
Data from: Model-based analysis supports interglacial refugia over long-dispersal events in the diversification of two South American cactus species
Pilosocereus machrisii and P. aurisetus are cactus species within the P. aurisetus complex, a group of eight cacti that are restricted to rocky habitats within the Neotropical savannas of eastern South America. Previous studies have suggested that diversification within this complex was driven by distributional fragmentation, isolation leading to allopatric differentiation, and secondary contact among divergent lineages. These events have been associated with Quaternary climatic cycles, leading to the hypothesis that the xerophytic vegetation patches which presently harbor these populations operate as refugia during the current interglacial. However, owing to limitations of the standard phylogeographic approaches used in these studies, this hypothesis was not explicitly tested. Here we use Approximate Bayesian Computation to refine the previous inferences and test the role of different events in the diversification of two species within P. aurisetus group. We used molecular data from chloroplast DNA and simple sequence repeats loci of P. machrisii and P. aurisetus, the two species with broadest distribution in the complex, in order to test if the diversification in each species was driven mostly by vicariance or by long-dispersal events. We found that both species were affected primarily by vicariance, with a refuge model as the most likely scenario for P. aurisetus and a soft vicariance scenario most probable for P. machrisii. These results emphasize the importance of distributional fragmentation in these species, and add support to the hypothesis of long-term isolation in interglacial refugia previously proposed for the P. aurisetus species complex diversification.
Data from: Evidence for the adaptive significance of secondary compounds in vertebrate-dispersed fruits
Although the primary function of fleshy fruits is to attract seed dispersers, many ripe fruits contain toxic secondary compounds. A number of hypotheses have been proposed to explain this evolutionary paradox, most of which describe the potential adaptive role secondary compounds may play in seed dispersal. However, some authors have argued that fruit secondary compounds may be non-adaptive, and instead explain their occurrence as a pleiotropic consequence of selection for defense of leaves and other tissues. We address these alternative evolutionary hypotheses through a comparative examination of iridoid glycosides in leaves, unripe fruits, and ripe fruits of Lonicera x bella (Belle's bush honeysuckle), combined with an examination of fruit damage and removal in natural populations. We provide several lines of evidence that fruit secondary compounds cannot be explained solely as a consequence of foliar defense, including higher concentrations and more individual compounds in fruits compared to leaves and a negative relationship between iridoid glycoside concentration and fruit damage. However, we also show that the composition and concentrations of secondary compounds in leaves and fruits are not entirely independent, emphasizing that selection in different plant parts is intrinsically linked. We conclude that the adaptive significance of chemical traits is best considered in a whole-plant context that includes fruit-frugivore interactions.
Data from: Inferring dispersal across a fragmented landscape using reconstructed families in the Glanville fritillary butterfly
Dispersal is important for determining both a species ecological processes, such as population viability, and its evolutionary processes, like gene flow and local adaptation. Yet obtaining accurate estimates in the wild through direct observation can be challenging or even impossible, particularly over large spatial and temporal scales. Genotyping many individuals from wild populations can provide detailed inferences about dispersal. We therefore utilized genomewide marker data to estimate dispersal in the classic metapopulation of the Glanville fritillary butterfly (Melitaea cinxia L.), in the Åland Islands in SW Finland. This is an ideal system to test the effectiveness of this approach due to the wealth of information already available covering dispersal across small spatial and temporal scales, but lack of information at larger spatial and temporal scales. We sampled three larvae per larval family group from 3,732 groups over a six-year period and genotyped for 272 SNPs across the genome. We used this empirical dataset to reconstruct cases where full-sibs were detected in different local populations to infer female effective dispersal distance, i.e. dispersal events directly contributing to gene flow. On average this was one kilometer, closely matching previous dispersal estimates made using direct observation. To evaluate our power to detect full-sib families we performed forward simulations using an individual-based model constructed and parameterized for the Glanville fritillary metapopulation. Using these simulations 100% of predicted full-sibs were correct and over 98% of all true full-sib pairs were detected. We therefore demonstrate that even in a highly dynamic system with a relatively small number of markers, we can accurately reconstruct full-sib families and for the first time make inferences on female effective dispersal. This highlights the utility of this approach in systems where it has previously been impossible to obtain accurate estimates of dispersal over both ecological and evolutionary scales.
Data from: Phylogeography of poorly dispersing net-winged beetles: a role of drifting India in the origin of Afrotropical and Oriental fauna
Ancient dispersal history may be obscured by subsequent dispersal events. Therefore, we intend to investigate the biogeography of metriorrhynchine net-winged beetles, a group characterized by limited dispersal propensity. We used DNA data to construct phylogenies and the BayesTraits and RASP programs to identify putative ancestral areas. Further, we inferred ultrametric trees to estimate the ages of selected nodes. The time frame is inferred from tectonic calibrations and the general mutation rate of the mitochondrial genes. Metriorrhynchini consists of two lineages with Afro/Oriental and Australian distributions. The basal lineages originated in Eastern Gondwana after the split of Australia, India and Madagascar; the Afrotropical and Madagascar Metriorrhynchini separated from the Oriental clades 65 and 62 mya. Several already diversified lineages colonized continental Asia 55–35 mya. A few genera of the Australian clade dispersed to the Oriental region 5–15 mya and reached Eastern India and Southern China. Only Xylobanus crossed the Makassar Strait to Sulawesi and does not occur further to the east. The current distribution of Metriorrhynchini is a result of drifting on continental fragments and over-sea dispersal events limited to a few hundreds of kilometers. We conclude that: (1) Afrotropical and Madagascar lineages originated independently from dispersal events during India's drift to the north and the Mozambique Channel completely isolates the respective faunas since then; (2) Oriental fauna is a recently established mixture of the Indian and Australian lineages, with predominance of the older Indian clades; (3) The fauna of islands located north of Australia colonized Sulawesi after collision with the Sundaland margin and the species rich Australian lineages did not reach Western Wallacea or the Philippines. Our results suggest an impact of subtle differences in biological characteristics on biogeographic history of individual lineages, when mostly lowland and flower-visiting lineages were able to disperse across sea channels.
Data from: Dispersal syndromes can impact ecosystem functioning in spatially structured freshwater populations
Dispersal can strongly influence ecological and evolutionary dynamics. Besides the direct contribution of dispersal to population dynamics, dispersers often differ in their phenotypic attributes from non-dispersers, which leads to dispersal syndromes. The consequences of such dispersal syndromes have been widely explored at the population and community level, however, to date, ecosystem-level effects remain unclear. Here, we examine whether dispersing and resident individuals of two different aquatic keystone invertebrate species have different contributions to detrital processing, a key function in freshwater ecosystems. Using experimental two-patch systems, we found no difference in leaf consumption rates with dispersal status of the common native species Gammarus fossarum. In Dikerogammarus villosus, however, a Ponto-Caspian species now expanding throughout Europe, dispersers consumed leaf litter at roughly three times the rate of non-dispersers. Furthermore, this put the contribution of dispersing D. villosus to leaf litter processing on par with native G. fossarum, after adjusting for differences in organismal size. Given that leaf litter decomposition is a key function in aquatic ecosystems, and the rapid species turnover in freshwater habitats with range expansions of non-native species, this finding suggests that dispersal syndromes may have important consequences for ecosystem functioning.
Data from: Beyond dispersal versus philopatry? Alternative behavioural tactics of juvenile roe deer in a heterogeneous landscape
Although inter-individual heterogeneity in many aspects of dispersal behaviour is widely reported, this key life-history trait is predominantly modelled as a dichotomous state of philopatry vs. dispersal. The increasing body of evidence for dispersal syndromes (i.e. a suite of correlated morphological, behavioural, and life-history traits associated with dispersal) implies substantial but, to date, undocumented individual heterogeneity in behavioural tactics during dispersal. Using a large sample (N = 154) of GPS monitored juvenile roe deer (<i>Capreolus capreolus</i>), we evaluated among-individual behavioural heterogeneity in dispersal tactics, and the individual and environmental drivers of these alternative tactics. We developed a sequential three-stage decision tree based on space use stability, exploration events and the directionality of movement. We identified six discrete alternative behavioural tactics during the dispersal period which were characterised by different timing, amplitude and duration in movement: slightly less than half of the deer were sedentary, either "strictly philopatric" or "explorers", which subsequently settled on their natal range; around 40% dispersed ("classic dispersal"), of which, one in six subsequently aborted, moving back to their natal range ("aborted dispersal"); finally, around 15% expressed either a "progressive dispersal" tactic, gradually moving away from their natal area to settle elsewhere, or a "multi-range" tactic. The propensity to express an alternative dispersal tactic was strongly influenced by an individual's local environment. In particular, when landscape heterogeneity, resource quality, and human-related disturbance in the natal range were low, individuals were (i) more likely to adopt the alternative tactics of either progressive dispersal or multi-ranging, but (ii) also more likely to abort their dispersal attempt. Our work indicates that natal dispersal is likely not a single uniform behaviour, but that individuals may adopt a variety of alternative movement tactics which are likely governed by different selection pressures, with potentially important impacts for population dynamics and functioning.
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.