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8,729 results for “Ranges”
Data from: Selfing ability and drift load evolve with range expansion
Colonization at expanding range edges often involves few founders, reducing effective population size. This process can promote the evolution of self-fertilization, but implicating historical processes as drivers of trait evolution is often difficult and requires an explicit model of biogeographic history. In plants, contemporary limits to outcrossing are often invoked as evolutionary drivers of self-fertilization, but historical expansions may shape mating system diversity, with leading-edge populations evolving elevated selfing ability. In a widespread plant, Campanula americana, we identified a glacial refugium in the southern Appalachian Mountains from spatial patterns of genetic drift among 24 populations. Populations farther from this refugium have smaller effective sizes and fewer rare alleles. They also displayed elevated heterosis in among-population crosses, reflecting the accumulation of deleterious mutations during range expansion. While populations with elevated heterosis had reduced segregating mutation load, the magnitude of inbreeding depression lacked geographic pattern. The ability to self-fertilize was strongly positively correlated with the distance from the refugium and mutation accumulation—a pattern that contrasts sharply with contemporary mate and pollinator limitation. In this and other species, diversity in sexual systems may reflect the legacy of evolution in small, colonizing populations, with little or no relation to the ecology of modern populations.
Data from: Abundance, survival, and annual rate of change in Cuvier's beaked whales (Ziphius cavirostris) on a Navy sonar range
<p>Bayesian mark-recapture estimates of survival, abundance, and trend are reported for Cuvier's beaked whales (<em>Ziphius cavirostris</em>) using a Navy training range off southern California. The deep-diving beaked whale family is exceptionally vulnerable to mid-frequency active sonar (MFAS), which has been implicated in mass strandings and altered foraging behavior. Extremely low sighting probabilities impede studies of population-level impacts of MFAS on beaked whales. The San Nicolas Basin hosts a Navy training range subject to frequent MFAS use and attracts high densities of <em>Z. cavirostris</em>. An eleven-year (2007–2018) photo-identification program leveraged automated acoustic detection and location capabilities on the range's 1,800-km<sup>2</sup> hydrophone array to enhance capture probability. Estimated population parameters for <em>Z. cavirostris </em>using the range included mean (90% credibility intervals) apparent annual survival of 0.950 (0.899–0.986), the annual number of individuals as 121 (71–219), and the annual rate of change of -0.8% (-5.6 – 4.1%). Simulations show the probability of detecting abundance changes is currently low, but can be greatly improved through continued monitoring and increased effort. Complementary data collection on habitat use and demographic rates in San Nicolas and surrounding basins is also essential to relating the direct effects of MFAS use to changes in vital rates and broader population outcomes.</p>
Under the radar: genetic assessment of Rio Grande Shiner (Notropis jemezanus) and Speckled Chub (Macrhybopsis aestivalis), two Rio Grande basin endemic cyprinids that have experienced recent range contractions
<p>The Rio Grande drainage of the southwestern United States and Mexico has undergone intense anthropogenic alteration by water diversions, extraction and associated habitat changes. These alterations have disproportionately impacted the pelagic broadcast spawning guild of minnows (pelagophils). Several Rio Grande endemic pelagophils, including the co-occurring Rio Grande Shiner (<i>Notropis jemezanus</i>) and Speckled Chub (<i>Macrhybopsis aestivalis</i>), have experienced dramatic recent range-wide declines yet have slipped under the radar of conservation efforts. The status of <i>N. jemezanus </i>and <i>M. aestivalis </i>in the Rio Grande and Pecos River was evaluated and standing genetic variation were characterized. Genetic evidence indicates that populations of both species found in the Rio Grande and Pecos River are genetically distinct. Additionally, 159 outlier loci were identified in <i>M. aestivalis </i>suggesting possible local adaptation in the Rio Grande and Pecos River populations. Though range-wide genetic data are limited, <i>N. jemezanus </i>populations in both rivers harbor considerable genetic diversity. Mitochondrial data from both taxa are consistent with a history of secondary contact between formerly isolated populations with deeply divergent haplotypes found within the Rio Grande and Pecos River populations of <i>N. jemezanus </i>and within the Rio Grande population of <i>M. aestivalis.</i> Extensive survey efforts in the lower Rio Grande and its tributaries in Texas document significant range contraction and near extirpation of <i>N. jemezanus </i>from this part of the basin; highlighting the need for immediate action to protect the species. </p>
Cuscuta sect. Californicae (Convolvulaceae) revisited: 'cryptic' speciation and host range differentiation
<p><i>Cuscuta californica</i> complex (sensu lato, s.l.) is a western North American group of species in which the infrastaminal scales are reduced, making the morphological delimitation of species particularly challenging. A revision of this group was prompted by the discovery of an apparent new species from central California based primarily on molecular means. Prompted by this finding, the morphological limits of <i>C. californica</i> s.l. species were comprehensively re-evaluated through a morphometric study. DNA sequences from plastid (<i>trnL–F</i> region and <i>rbcL</i>), nuclear ribosomal ITS and 26S rDNA, as well as a low-copy nuclear pentatricopeptide repeat (PPR) gene were used to reconstruct evolutionary relationships among taxa. Last but not least, the host range of relevant taxa was determined using herbarium specimens. Molecular results strongly supported the new species, <b><i>C. difficilis</i></b>, which was found to be morphologically separated from <i>C. brachycalyx</i> only by subtle calyx lobe and corolla tube shape differences. Despite sharing some of the hosts, all the members of <i>C. californica</i> s.l. exhibited a differentiation of their host ranges. An identification key and description of the new species were provided together with a discussion on the systematics and host range of <i>C. californica </i>s.l.. Hybridization, accompanied by plastid capture, was suggested as a possible mechanism of speciation for <i>C. brachycalyx</i>.</p>
Supplementary information for: The effects of geographic range size and abundance on extinction during a time of 'sluggish' evolution
<p>Geographic range size and abundance are important determinants of extinction risk in fossil and extant taxa. However, the relationship between these variables and extinction risk has not been tested extensively during evolutionarily 'quiescent' times of low extinction and speciation in the fossil record. Here we examine the influence of geographic range size and abundance on extinction risk during the late Paleozoic (Mississippian–Permian), a time of 'sluggish' evolution when global rates of origination and extinction were roughly half those of other Paleozoic intervals. Analyses used spatio-temporal occurrences for 164 brachiopod species from the North American midcontinent. We found abundance to be a better predictor of extinction risk than measures of geographic range size. Moreover, species exhibited reductions in abundance prior to their extinction, but did not display contractions in geographic range size. The weak relationship between geographic range size and extinction in this time and place may reflect the relative preponderance of larger-ranged taxa, combined with the physiographic conditions of the region that allowed for easy habitat tracking that dampened both extinction and speciation. These conditions led to a prolonged period (19 – 25 Myr) during which standard macroevolutionary rules did not apply.</p>
Autopolyploidy-driven range expansion of a temperate-originated plant to pan-tropic under global change
<p>Angiosperms are believed to have emerged initially in the tropics and expanded their distribution range polewards through diverse mechanisms, for example polyploidization-driven cold-tolerance evolution. Reversed expansion from temperate to pantropic climate through a polyploidization-driven shift in heat-tolerance remains largely unknown. Here, we found autopolyploidy in relation to the global expansion of <i>Solidago canadensis</i> from its temperate-climate native range in North American to hot-summer climate in an introduced range. Our cytogeographical study of 2062 accessions from 471 locations worldwide demonstrates that ploidy levels correlates negatively with latitude and positively with average temperature. An isotherm-dependent shift of the climate niches at the threshold of 20-24ºC between geo-cytotypes can be attributed mainly to autopolyploidy-driven differentiation of heat tolerance; only polyploids and not diploids are able to complete sexual reproduction, germinate and grow in the hot-summer climate of low latitudes. Ploidy-dependent fertility appears to play a key role in the hot-summer introduced range in the northern hemisphere through both pre-adaptation and rapid post-introduction adaptive evolution of delayed flowering and improved heat-tolerance during embryo development. MaxEnt model predicts continuous expansion of this weed under global change. These results provide new insights into the mechanisms governing autopolyploidy-driven backward range-expansion of plant species from temperate origins.</p>
Co-seismic and post-seismic differential Interferograms and displacement maps for the 2020 M6.5 Monte Cristo Range, Nevada earthquake
<p>Differential interferograms for the Mw 6.5 Monte Cristo, Nevada earthquake, processed with SNAP and CNR-IREA P-SBAS in the <a href="https://geohazards-tep.eu">Geohazards Exploitation Platform</a>.</p> <p>USGS event page for the Monte Cristo earthquake:</p> <p><a href="https://earthquake.usgs.gov/earthquakes/eventpage/nn00725272/">https://earthquake.usgs.gov/earthquakes/eventpage/nn00725272/</a></p> <p>Co-seismic and post-seismic (May 16 - May 23) interferograms are included. For each interferometric pair, three products are included: coherence, phase interferogram and unwrapped interferogram (LOS displacement). Decomposition.zip files includes the processed East-West and Vertical deformation maps from combining ascending and descending interferograms.</p> <p> </p>
Spatial and temporal dynamics of space use by free-ranging domestic dogs Canis familiaris in rural Africa
<p>Variation in the spatial ecology of animals influences the transmission of infections and so understanding host behaviour can improve the control of diseases. Despite the global distribution of free-ranging domestic dogs <i>Canis familiaris</i> and their role as reservoirs for zoonotic diseases, little is known about the dynamics of their space use. We deployed GPS loggers on free-ranging dogs from six villages in rural Chad, and tracked the movements of 174 individuals in the dry season and 151 in the wet season. We calculated 95% and core home ranges using auto-correlated kernel density estimates (AKDE<sub>95</sub> and AKDE<sub>core</sub>), determined the degree to which their movements were predictable, and identified correlates of movement patterns. The median AKDE<sub>95 </sub>range in the dry season was 0.54km<sup>2</sup> and in the wet season was 0.31km<sup>2</sup>, while the median AKDE<sub>core </sub>range in the dry season was 0.08km<sup>2</sup> and in the wet season was 0.04km<sup>2</sup>. Seasonal variation was, in part, related to owner activities. Dogs from hunting households had ranges that were five times larger in the dry season. At least 70% of individuals were more predictably 'at home' (<50m from the household) throughout the day in the dry season. 80% of dogs demonstrated periodicity in activity levels (speed) and just over half the dogs exhibited periodicity in location (repeated space use). In the wet season, dogs mostly exhibited 24-hour cycles in activity and location, with peaks at midday. In the dry season, dogs exhibited both 12 and 24-hour cycles, with either a single peak at midday, or one peak between 6am and 12 noon and a second between 6 and 10pm. Strategies to control canine-mediated zoonoses can be improved by tailoring operations to the local spatial ecology of free-ranging dogs. Interventions using a door-to-door strategy in rural Chad would best conduct operations during the dry season, when access to dogs around their household more reliably exceeds 70% throughout the day. Given the importance of use in hunting for explaining variation in dog space-use, targeting approaches to disease control at the household level on the basis of owner activities offers potential to improve access to dogs.</p>
Weather variation affects the dispersal of grasshoppers beyond their elevational ranges
<p><span><span><span><span><span><span><span><span><span><span><span>Understanding how abiotic conditions influence dispersal patterns of organisms is important for understanding the degree to which species can track and persist in the face of changing climate. </span></span></span></span></span></span></span></span></span></span></span><span><span><span><span><span><span><span><span><span><span><span><span><span>The goal of this study was to understand how weather conditions (temperature, precipitation and wind patterns) influence the dispersal patterns of multiple non-migratory grasshopper species from lower elevation grassland habitats in which they complete their life-cycles to higher elevations that extend beyond their range limits. The study also explored the role of weather factors (temperature and precipitation) in influencing the population sizes of species found at lower elevations. </span></span></span></span></span></span></span></span></span></span></span></span></span></p>
Dead litter of resident species first facilitates and then inhibits sequential life stages of range-expanding species
<p>1. Resident species can facilitate invading species (biotic assistance) or inhibit their expansion (biotic resistance). Species interactions are often context-dependent and the relative importance of biotic assistance versus resistance could vary with abiotic conditions or the life stage of the invading species, as invader stress tolerances and resource requirements change with ontogeny. In northeast Florida salt marshes, the abundant dead litter (wrack) of the native marsh cordgrass, <em>Spartina alterniflora</em>, could influence the expansion success of the black mangrove, <em>Avicennia germinans</em>, a tropical species that is expanding its range northward.</p> <p>2. We used two field experiments to examine how <em>S. alterniflora</em> wrack affects <em>A. germinans</em> success during 1) propagule establishment and 2) subsequent seedling survival. We also conducted laboratory feeding assays to identify propagule consumers and assess how wrack presence influences herbivory on mangrove propagules.</p> <p>3. <em>S. alterniflora</em> wrack facilitated <em>A. germinans </em>establishment by promoting propagule recruitment, retention, and rooting; the tidal regime influenced the magnitude of these effects. However, over time <em>S. alterniflora</em> wrack inhibited <em>A. germinans</em> seedling success by smothering seedlings and attracting herbivore consumers. Feeding assays identified rodents – which seek refuge in wrack – as consumers of<em> A. germinans </em>propagules.</p> <p>4. Synthesis: Our results suggest that the deleterious effects of <em>S. alterniflora</em> wrack on <em>A. germinans</em> seedling survival counterbalance the initial beneficial effects of wrack on <em>A. germinans</em> seed establishment. Such seed-seedling conflicts can arise when species stress tolerances and resource requirements change throughout development and vary with abiotic conditions. In concert with the tidal conditions, the relative importance of positive and negative interactions with wrack at each life stage can influence the rate of local and regional mangrove expansion. Because interaction strengths can change in direction and magnitude with ontogeny, it is essential to examine resident-invader interactions at multiple life stages and across environmental gradients to uncover the mechanisms of assistance and resistance during invasion.</p>
Prevalence of Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans in thre Hoang Lien Range, northwest Vietnam
<p>This study aims to investigate the presence of the amphibian chytrid fungi <i>Batrachochytrium dendrobatidis </i>(<i>Bd</i>) and<i> Batrachochytrium salamandrivorans </i>(<i>Bsal</i>)<i> </i>in the <a name="_Hlk45376654">Hoang Lien Range, northwest Vietnam </a>as well as any patterns in <i>Bd</i> infection in space, time and host species over a five-year sampling period. This study also aims to investigate the presence of <i>Bsal</i> in the Hoang Lien Range.</p>
First detection of herpesvirus and mycoplasma in free-ranging Hermann's tortoises (Testudo hermanni), and in potential pet vectors
<p>Two types of pathogens cause highly contagious upper respiratory tract diseases (URTD) in Chelonians: testudinid herpesviruses (TeHV) and a mycoplasma (<em>Mycoplasma agassizii</em>). In captivity, these infections are frequent and can provoke outbreaks. Pet trade generates international flow of tortoises, often without sanitary checking; individuals intentionally or accidentally released in the wild may spread pathogens. A better understanding of the transmission of infectious agents from captivity to wild tortoises is needed. Many exotic individuals have been introduced in populations of the endangered western Hermann’s tortoise (<em>Testudo hermanni hermanni</em>), notably spur-thighed tortoises (<em>Testudo graeca</em>). We assessed the presence of TeHV and mycoplasma in native western Hermann’s tortoises and in potential pet vectors in south-eastern France. Using a large sample (N=572 tortoises), this study revealed the worrying presence of herpesvirus in 7 free-ranging individuals (3 sub-populations). Additionally, <em>Mycoplasma agassizii</em> was detected in 15 of the 18 populations sampled with a frequency ranging from 2.5 to 25%. Exotic spur-thighed tortoises showed high frequency of <em>Mycoplasma </em>infection in captivity (18%) and in individuals (50%) found in native Hermann’s tortoise sub-populations, suggesting that this species could be a significant vector. The paucity of information of TeHV on European tortoise’ URTD in natural settings, especially in combination with mycoplasma, prompts for further studies. Indeed, sick tortoises remain concealed and may not be easily detected in the field. Our results indicate that both the prevalence and health impact of URTD are high should be scrutinized in the field.</p>
Oceanographic habitat location data to support range shift analyses for the manuscript: "Climate-driven range shifts are rapid yet variable among recreationally important coastal-pelagic fishes"
<p>This data file contains the latitudinal location of suitable oceanographic habitat for a suite of coastal-pelagic fishes off eastern Australia at monthly time-steps between 1998 and 2018. Please refer to the manuscript "Climate-driven range shifts are rapid yet variable among recreationally important coastal-pelagic fishes" for a full description of the methodologies applied to derive these data.</p>
Primary hybrid zone formation in Tephroseris helenitis (Asteraceae), following postglacial range expansion along the central Northern Alps
<p>Secondary vs. primary hybrid zone formation remains a challenging task as the time window in which these historical (vicariant) vs. contemporary (environmental-selective) processes are distinguishable may be relatively narrow.</p> <p>To examine the origin and structure of a transition zone between two subspecies of <i>Tephroseris helenitis</i> along the central Northern Alps, molecular (AFLP) and morphological (achene type) data as well as ecological niche models (ENMs) were used. Samples were collected over a <i>c.</i> 350 km-long transect, largely covered by ice during the Last Glacial Maximum (LGM).</p> <p>Genetically non-admixed individuals of subspp. <i>helenitis</i> vs. <i>salisburgensis</i> dominated the westernmost vs. eastern transect areas, with admixed individuals occurring in between. Cline for achene morphology was steep, largely non-coincidental, and displaced to the east of the cline centre for neutral AFLPs. During the LGM, ssp. <i>helenitis</i> should have been able to persist in a refugium southwest of the transect, while suitable habitat for ssp. <i>salisburgensis</i> was apparently absent at this time.</p> <p>Patterns of genetic and clinal variation in combination with our ENM data are suggestive of a primary hybrid zone that originated after the species' postglacial, eastward expansion.</p> <p> </p>
Data from: Testing range-limit hypotheses using range-wide habitat suitability and occupancy for the scarlet monkeyflower (Erythranthe cardinalis)
Determining the causes of geographic range limits is a fundamental problem in ecology, evolution, and conservation biology. Range limits arise due to fitness and dispersal limitation, which yield contrasting predictions about habitat suitability and occupancy of suitable habitat across geographic ranges. If a range edge is limited primarily by fitness, occupancy of suitable habitat should be high, habitat suitability should decline towards the edge, and no suitable habitat should exist beyond it. In contrast, a range edge limited primarily by dispersal should have unoccupied but suitable habitat at and beyond the edge. We built ecological niche models relating occurrence records for the scarlet monkeyflower (Erythranthe cardinalis) to climatic variables, and applied these models to independent data from systematic, range-wide surveys of presence and absence to estimate the availability and occupancy of climatically suitable habitat. We found that fitness limitation predominated over dispersal limitation, but dispersal limitation also played a role at the poleward edge. These results are consistent with the hypothesis that dispersal limitation is more important along shallow environmental gradients and also suggest that synergy between dispersal and fitness limitation can contribute to colonization failure. The framework used here is validated by independent data and could be readily applied to inferring causes of range limits in many other species.
Data from: Adaptive evolution to novel predators facilitates the evolution of damselfly species range shifts
Most species have evolved adaptations to reduce the chances of predation. In many cases adaptations to coexist with one predator generate tradeoffs in the ability to live with other predators. Consequently, the ability to live with one predator may limit the geographic distributions of species, such that adaptive evolution to coexist with novel predators may facilitate range shifts. In a case study with Enallagma damselflies, we used a comparative phylogenetic approach to test the hypothesis that adaptive evolution to live with a novel predator facilitates range size shifts. Our results suggest that the evolution of Enallagma shifting from living in ancestral lakes with fish as top predators, to living in lakes with dragonflies as predators, may have facilitated an increase in their range sizes. This increased range size likely arose because lakes with dragonflies were widespread, but unavailable as a habitat throughout much of the evolutionary history of Enallagma because they were historically maladapted to coexist with dragonfly predators. Additionally, the traits that have evolved as defenses against dragonflies also likely enhanced damselfly dispersal abilities. While many factors underlie the evolutionary history of species ranges, these results suggest a role for the evolution of predator-prey interactions.
Long-term movements and home range changes: rapid territory shifts in meerkats
<p>1. Territoriality and stable home ranges are a common space use pattern among animals. These ranges provide its inhabitants with important resources and thus favourable territories are associated with an increased fitness. While the role of territory quality and changes of territory ownership have often been investigated, the changes of territorial boundaries have been less studied.</p> <p>2. Here we investigated space use changes in a social mammal species, applying a novel analytical approach, calculating long-term dissimilarity in space use using distance matrices based on periodic utilization distributions. This approach makes it possible to identify different space use patterns, which cannot be distinguished by only considering changes between consecutive time periods.</p> <p>3. We analysed meerkat (Suricata suricatta) movements of a total of 24 different groups over a 16-year period, resulting in 134 group years. We then correlated the identified home range changes to life history events and possible environmental drivers.</p> <p>4. Groups had stable territories for several years before they abandoned their home range mostly to move quickly to new areas where they again remained for several years. Of 26 identified sudden shifts, 22 occurred in the summer months and often involved distances larger than the original home range size. Home-range movements that were close together in time were often also spatially clustered and moved in a similar direction. These shifts were often preceded by more frequent interactions between groups, but did not seem to be a product of direct displacements by other groups. The normalized difference vegetation index (NDVI) as a measure of food production and social factors such as dominance changes did not correlate to changes.</p> <p>5. Against our expectation space use changes were not accumulations of small changes, but more often involved long distance moves into unknown ranges. This means that the groups enter areas where they cannot profit from local knowledge. The methods used identifies episodes of long stability alternated by sudden changes in meerkats and in general provides insight into long-term space use. Our methods can be used to analyse long-term space use, either within or across species.</p>
Data from: Overcoming the challenge of small effective sample sizes in home-range estimation
Technological advances have steadily increased the detail of animal tracking datasets, yet fundamental data limitations exist for many species that cause substantial biases in home‐range estimation. Specifically, the effective sample size of a range estimate is proportional to the number of observed range crossings, not the number of sampled locations. Currently, the most accurate home‐range estimators condition on an autocorrelation model, for which the standard estimation frame‐works are based on likelihood functions, even though these methods are known to underestimate variance—and therefore ranging area—when effective sample sizes are small. Residual maximum likelihood (REML) is a widely used method for reducing bias in maximum‐likelihood (ML) variance estimation at small sample sizes. Unfortunately, we find that REML is too unstable for practical application to continuous‐time movement models. When the effective sample size N is decreased to N ≤ urn:x-wiley:2041210X:media:mee313270:mee313270-math-0001(10), which is common in tracking applications, REML undergoes a sudden divergence in variance estimation. To avoid this issue, while retaining REML's first‐order bias correction, we derive a family of estimators that leverage REML to make a perturbative correction to ML. We also derive AIC values for REML and our estimators, including cases where model structures differ, which is not generally understood to be possible. Using both simulated data and GPS data from lowland tapir (Tapirus terrestris), we show how our perturbative estimators are more accurate than traditional ML and REML methods. Specifically, when urn:x-wiley:2041210X:media:mee313270:mee313270-math-0002(5) home‐range crossings are observed, REML is unreliable by orders of magnitude, ML home ranges are ~30% underestimated, and our perturbative estimators yield home ranges that are only ~10% underestimated. A parametric bootstrap can then reduce the ML and perturbative home‐range underestimation to ~10% and ~3%, respectively. Home‐range estimation is one of the primary reasons for collecting animal tracking data, and small effective sample sizes are a more common problem than is currently realized. The methods introduced here allow for more accurate movement‐model and home‐range estimation at small effective sample sizes, and thus fill an important role for animal movement analysis. Given REML's widespread use, our methods may also be useful in other contexts where effective sample sizes are small.
Data from: Population genomics and demographic sampling of the ant-plant Vachellia drepanolobium and its symbiotic ants from sites across its range in East Africa.
The association between the African ant plant, Vachellia drepanolobium, and the ants that inhabit it has provided insight into the boundaries between mutualism and parasitism, the response of symbioses to environmental perturbations, and the ecology of species coexistence. We use a landscape genomics approach at sites sampled throughout the range of this system in Kenya to investigate the demographics and genetic structure of the different partners in the association. We find that different species of ant associates of V. drepanolobium show striking differences in their spatial distribution throughout Kenya, and these differences are only partly correlated with abiotic factors. A comparison of the population structure of the host plant and its three obligately arboreal ant symbionts, Crematogaster mimosae, Crematogaster nigriceps, and Tetraponera penzigi, shows that the ants exhibit somewhat similar patterns of structure throughout each of their respective ranges, but that this does not correlate in any clear way with the respective genetic structure of the populations of their host plants. A lack of evidence for local coadaptation in this system suggests that all partners have evolved to cope with a wide variety of biotic and abiotic conditions.
Data from: Herbarium specimens reveal a historical shift in phylogeographic structure of common ragweed during native range disturbance
Invasive plants provide ample opportunity to study evolutionary shifts that occur after introduction to novel environments. However, although genetic characters pre-dating introduction can be important determinants of later success, large-scale investigations of historical genetic structure have not been feasible. Common ragweed (Ambrosia artemisiifolia L.) is an invasive weed native to North America that is known for its allergenic pollen. Palynological records from sediment cores indicate that this species was uncommon before European colonization of North America, and ragweed populations expanded rapidly as settlers deforested the landscape on a massive scale, later becoming an aggressive invasive with populations established globally. Toward a direct comparison of genetic structure now and during intense anthropogenic disturbance of the late 19th century, we sampled 45 natural populations of common ragweed across its native range as well as historical herbarium specimens collected up to 140 years ago. Bayesian clustering analyses of 453 modern and 473 historical samples genotyped at three chloroplast spacer regions and six nuclear microsatellite loci reveal that historical ragweed's spatial-genetic structure mirrors both the paleo-record of Ambrosia pollen deposition and the historical pattern of agricultural density across the landscape. Furthermore, for unknown reasons this spatial-genetic pattern has changed substantially in the intervening years. Following on previous work relating morphology and and genetic expression between plants collected from eastern North America and Western Europe, we speculate that the cluster associated with humans' rapid transformation of the landscape is a likely source of these aggressive invasive populations.
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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.