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3,655 results for “Structural data”
Data from: Influence of the larval phase on connectivity: strong differences in the genetic structure of brooders and broadcasters in the Ophioderma longicauda species complex
Closely related species with divergent life-history traits are excellent models to infer the role of such traits in genetic diversity and connectivity. Ophioderma longicauda is a brittle star species complex composed of different genetic clusters, including brooders and broadcasters. These species diverged very recently and some of them are sympatric and ecologically syntopic, making them particularly suitable to study the consequences of their trait differences. At the scale of the geographic distribution of the broadcasters (Mediterranean Sea and north-eastern Atlantic), we sequenced the mitochondrial marker COI and genotyped an intron (i51) for 788 individuals. In addition, we sequenced 10 nuclear loci newly developed from transcriptome sequences, for six sympatric populations of brooders and broadcasters from Greece. At the large scale we found a high genetic structure within the brooders (COI: 0.07
Data from: Genetic diversity and population structure of the tsetse fly Glossina fuscipes fuscipes (Diptera: Glossinidae) in Northern Uganda: implications for vector control
Uganda is the only country where the chronic and acute forms of human African Trypanosomiasis (HAT) or sleeping sickness both occur and are separated by < 100 km in areas north of Lake Kyoga. In Uganda, Glossina fuscipes fuscipes is the main vector of the Trypanosoma parasites responsible for these diseases as well for the animal African Trypanosomiasis (AAT), or Nagana. We used highly polymorphic microsatellite loci and a mitochondrial DNA (mtDNA) marker to provide fine scale spatial resolution of genetic structure of G. f. fuscipes from 42 sampling sites from the northern region of Uganda where a merger of the two disease belts is feared. Based on microsatellite analyses, we found that G. f. fuscipes in northern Uganda are structured into three distinct genetic clusters with varying degrees of interconnectivity among them. Based on genetic assignment and spatial location, we grouped the sampling sites into four genetic units corresponding to northwestern Uganda in the Albert Nile drainage, northeastern Uganda in the Lake Kyoga drainage, western Uganda in the Victoria Nile drainage, and a transition zone between the two northern genetic clusters characterized by high level of genetic admixture. An analysis using HYBRIDLAB supported a hybrid swarm model as most consistent with tsetse genotypes in these admixed samples. Results of mtDNA analyses revealed the presence of 30 haplotypes representing three main haplogroups, whose location broadly overlaps with the microsatellite defined clusters. Migration analyses based on microsatellites point to moderate migration among the northern units located in the Albert Nile, Achwa River, Okole River, and Lake Kyoga drainages, but not between the northern units and the Victoria Nile drainage in the west. Effective population size estimates were variable with low to moderate sizes in most populations and with evidence of recent population bottlenecks, especially in the northeast unit of the Lake Kyoga drainage. Our microsatellite and mtDNA based analyses indicate that G. f. fuscipes movement along the Achwa and Okole rivers may facilitate northwest expansion of the Rhodesiense disease belt in Uganda. We identified tsetse migration corridors and recommend a rolling carpet approach from south of Lake Kyoga northward to minimize disease dispersal and prevent vector re-colonization. Additionally, our findings highlight the need for continuing tsetse monitoring efforts during and after control.
Data from: Genetic structure of a naturally regenerating post-fire seedling population: Pinus halepensis as a case study
To study the effects of wildfire on population genetics of a wind pollinated and wind dispersed tree, we have analyzed the genetic structure of a post-fire, naturally regenerating seedling population of Pinus halepensis Miller, on Mt. Carmel, Israel. We tested the existence of spatial genetic structure, which is expected due to the special spatial demographic structure of the post-fire seedling and sapling populations of this species. Explicitly, we asked whether or not seedlings that germinated under large, burned, dead pine trees are also their offspring. The results revealed that the post-fire seedling population is polymorphic, diverse, and reflects the pre-fire random mating system. In contrast to our prediction, we found no division of the post-fire seedling population to distinct sub-populations. Furthermore, as a result of post-fire seed dispersal to longer range than the average pre-fire inter-tree distance, seedlings found under individual burned trees were not necessarily their sole offspring. Although the population as a whole showed a Hardy-Weinberg equilibrium, significant excess of heterozygotes was found within each tallest seedlings group growing under single, large, burned pine trees. Our finding indicates the possible existence of intense natural selection for the most vigorous heterozygous genotypes that are best adapted to the special post-fire regeneration niche, which is the thick ash bed under large, dead, pine trees.
Data from: Population genetic structure and connectivity of deep-sea stony corals (Order Scleractinia) in the New Zealand region: implications for the conservation and management of Vulnerable Marine Ecosystems
Deep-sea stony corals, which can be fragile, long-lived, late to mature and habitat-forming, are defined as vulnerable marine ecosystem indicator taxa. Under United Nations resolutions these corals require protection from human disturbance such as fishing. To better understand the vulnerability of stony corals (Goniocorella dumosa, Madrepora oculata, Solenosmilia variabilis) to disturbance within the New Zealand region, and to guide marine protected area design, genetic structure and connectivity were determined using microsatellite loci and DNA sequencing. Analyses compared population genetic differentiation between two biogeographic provinces, amongst three sub-regions (north-central-south), and amongst geomorphic features. Extensive population genetic differentiation was revealed by microsatellite variation, whilst DNA sequencing revealed very little differentiation. For G. dumosa, genetic differentiation existed amongst regions and geomorphic features, but not between provinces. For M. oculata, only a north-central-south regional structure was observed. For S. variabilis, genetic differentiation was observed between provinces, amongst regions and amongst geomorphic features. Populations on the Kermadec Ridge were genetically different from Chatham Rise populations in all three species. A significant isolation-by-depth pattern was observed for both marker types in G. dumosa, and also in ITS of M. oculata. An isolation-by-distance pattern was revealed for microsatellite variation in S. variabilis. Medium to high levels of self-recruitment were detected in all geomorphic populations, and rates and routes of genetic connectivity were species-specific. These patterns of population genetic structure and connectivity at a range of spatial scales indicate that flexible spatial management approaches are required for the conservation of deep-sea corals around New Zealand.
Data from: Genetic co-structure in a meta-community under threat of habitat fragmentation
Habitat fragmentation increasingly threatens the services provided by natural communities and ecosystem worldwide. An understanding of the eco-evolutionary processes underlying fragmentation-compromised communities in natural settings is lacking, yet critical to realistic and sustainable conservation. Through integrating the multivariate genetic, biotic and abiotic facets of a natural community module experiencing various degrees of habitat fragmentation, we provide unique insights into the processes underlying community functioning in real, natural conditions. The focal community module comprises a parasitic butterfly of conservation concern, and its two obligatory host species, a plant and an ant. We show that both historical dispersal and ongoing habitat fragmentation shape population genetic diversity of the butterfly Phengaris alcon and its most limited host species (the plant Gentiana pneumonanthe). Genetic structure of the individual species was strongly driven by geographical structure, altitude and landscape connectivity. Strikingly, however, was the strong degree of genetic co-structure among the three species that could not be explained by the spatial variables under study. This finding suggests that factors other than spatial configuration, including co-evolutionary dynamics and shared dispersal pathways, cause parallel genetic structure among interacting species. While the exact contribution of coevolution and shared dispersal routes on the genetic variation within and among communities deserves further attention, our findings demonstrate a considerable degree of genetic parallelism in natural meta-communities. The significant effect of landscape connectivity on the genetic diversity and structure of the butterfly also suggests that habitat fragmentation may threaten the functioning of the community module on the long run.
Data from: Parallel evolution of jugal structures in Devonian athyridide brachiopods
Here, we describe Sinathyris crassa gen. et sp. nov., a new early Emsian (Early Devonian) athyridide brachiopod with a double spiralium from the Guangxi Province of southern China. Unlike the majority of genera of the subfamily Helenathyridinae, which possess accessory spiral lamellae developed directly from the jugal branches, the form described here shows these lamellae arising from a distally bifurcating jugal stem. These differences suggest that the double spiralium in S. crassa might have appeared independently from the double spiralium of the helenathyridins. To test the subfamily assignment of Sinathyris gen. nov., we carried out phylogenetic analyses, which indicate that the new genus is more appropriately referred to the Didymothyridinae. The cladistic analyses of the athyridides indicate that double spiralia have developed independently among these brachiopods at least five times during their evolutionary history.
Data from: Connectivity explains local ant community structure in a Neotropical forest canopy: a large-scale experimental approach
Understanding how habitat structure and resource availability affect local species distributions is a key goal of community ecology. Where habitats occur as a mosaic, variation in connectivity among patches influences both local species richness and composition, and connectivity is a key conservation concern in fragmented landscapes. Similarly, availability of limiting resources frequently determines species co-existence or exclusion. For primarily cursorial arthropods like ants, gaps between neighboring trees are a significant barrier to movement through the forest canopy. Competition for limited resources such as nest sites also promotes antagonistic interactions. Lianas (woody vines) connect normally isolated neighboring tree crowns and often have hollow stems inhabited by ants. We used two large-scale liana removal experiments to determine how connectivity and nest site availability provided by lianas affect arboreal ant species richness, species composition, and β-diversity in a lowland tropical forest in Panama. Removing lianas from a tree crown reduced ant species richness up to 35%, and disproportionately affected species that require large foraging areas. Adding artificial connectivity to trees mitigated the effects of liana removal. Ant colonization of artificial nests was higher (73% occupied) in trees without lianas vs. trees with lianas (28% occupied). However, artificial nests typically were colonized by existing polydomous, resident ant species. As a result, nest addition did not affect ant community structure. Collectively, these results indicate that lianas are important to the maintenance of arboreal ant diversity specifically by providing connectivity among neighboring tree crowns. Anticipated increases in liana abundance in this forest could increase the local (tree-level) species richness of arboreal ants, with a compositional bias toward elevating the density of broad-ranging specialist predators.
Data from: Regional and local patterns of genetic variation and structure in yellow-necked mice − the roles of geographic distance, population abundance and winter severity
The goal of this study, conducted in seven large woodlands and three areas with small woodlots in north-eastern Poland in 2004-2008, was to infer genetic structure in yellow-necked mouse Apodemus flavicollis population and to evaluate the roles of environmental and population ecology variables in shaping the spatial pattern of genetic variation using 768 samples genotyped at 13 microsatellite loci. Genetic variation was very high in all studied regions. The primal genetic subdivision was observed between the northern and the southern parts of the study area, which harboured two major clusters and the intermediate area of highly admixed individuals. The probability of assignment of individual mice to the northern cluster increased significantly with lower temperatures of January and July and declined in regions with higher proportion of deciduous and mixed forests. Despite the detected structure, genetic differentiation among regions was very low. Fine-scale structure was shaped by the population density, whereas higher level structure was mainly shaped by geographic distance. Genetic similarity indices were highly influenced by mouse abundance (which positively correlated with the share of deciduous forests in the studied regions) and exhibited the greatest change between 0 and 1 km in the forests, 0 and 5 km in small woodlots. Isolation by distance pattern, calculated among regions, was highly significant but such relationship between genetic and geographic distance was much weaker, and held the linearity at very fine scale (~1.5 km), when analyses were conducted at individual level.
Data from: Description and preliminary results from a structured specialist behavioural weight management group intervention: Specialist Lifestyle Management (SLiM) Programme
Background: Specialist Lifestyle Management (SLiM) is a structured patient education and self-management group weight management programme. Each session is run monthly over a 6-month period providing a less intensive long-term approach. The groups are patient-centred incorporating educational, motivational, behavioural and cognitive elements. The theoretical background, programme structure and preliminary results of SLiM are presented. Subjects/methods: The study was a pragmatic service evaluation of obese patients with a body mass index (BMI) ≥35 kg/m2 with comorbidity or ≥40 kg/m2 without comorbidity referred to a specialist weight management service in the West Midlands, UK. 828 patients were enrolled within SLiM over a 48-month period. Trained facilitators delivered the programme. Preliminary anonymised data were analysed using the intention-to-treat principle. The primary outcome measure was weight loss at 3 and 6 months with comparisons between completers and non-completers performed. The last observation carried forward was used for missing data. Results: Of the 828 enrolled within SLiM, 464 completed the programme (56%). The mean baseline weight was 135 kg (BMI=49.1 kg/m2) with 87.2% of patients having a BMI≥40 kg/m2 and 12.4% with BMI≥60 kg/m2. The mean weight change of all patients enrolled was −4.1 kg (95% CI −3.6 to −4.6 kg, p=0.0001) at the end of SLiM, with completers (n=464) achieving −5.5 kg (95% CI −4.2 to −6.2 kg, p=0.0001) and non-completers achieving −2.3 kg (p=0.0001). The majority (78.6%) who attended the 6-month programme achieved weight loss with 32.3% achieving a ≥5% weight loss. Conclusions: The SLiM programme is an effective group intervention for the management of severe and complex obesity.
Data from: Nuclear DNA based species delineations of Coccus scale insects in symbiosis with plants and ants, and the role of plant epicuticular wax in structuring associations
We undertook phylogenetic analysis of nuclear DNA to elucidate species boundaries in the symbiotic Coccus scale insects associated with mutualistic Crematogaster ants and Macaranga plants occurring in the ever-wet forests of Southeast Asia. The coccid specimens clustered into ten lineages, each corresponding to a morphospecies assignment. The lineage identified as C. secretus was separated from the Main Clade by an outgroup. We also examined all pairwise associations among the three symbiont guilds to understand how patterns of association were structured. The analyses revealed that each ant, plant or coccid operational (taxonomic) unit often associated with multiple O(T)Us of each of the other two guilds. However, where testing was feasible, a 'preference' for one or sometimes two partner O(T)Us of each guild was often detected. Mutual 'preferences' or 'avoidances' were relatively common among the symbionts, and no conflicts of interest were apparent. The network of preferred partners among all three guilds showed compartmentalization structured by the presence/absence of plant epicuticular wax, suggesting that this feature plays a fundamental role in how the symbionts select partners that best serve their needs. To a lesser degree, the network was also structured by whether the host plant stems were ant-excavated or hollowed naturally.
Data from: Strong population structure in a species manipulated by humans since the Neolithic: the European fallow deer (Dama dama dama)
Species that have been translocated and otherwise manipulated by humans may show patterns of population structure that reflect those interactions. At the same time, natural processes shape populations, including behavioural characteristics like dispersal potential and breeding system. In Europe, a key factor is the geography and history of climate change through the Pleistocene. During glacial maxima throughout that period, species in Europe with temperate distributions were forced south, becoming distributed among the isolated peninsulas represented by Anatolia, Italy and Iberia. Understanding modern patterns of diversity depends on understanding these historical population dynamics. Traditionally, European fallow deer (Dama dama dama) are thought to have been restricted to refugia in Anatolia and possibly Sicily and the Balkans. However, the distribution of this species was also greatly influenced by human-mediated translocations. We focus on fallow deer to better understand the relative influence of these natural and anthropogenic processes. We compared modern fallow deer putative populations across a broad geographic range using microsatellite and mitochondrial DNA loci. The results revealed highly insular populations, depauperate of genetic variation and significantly differentiated from each other. This is consistent with the expectations of drift acting on populations founded by small numbers of individuals, and reflects known founder populations in the north. However, there was also evidence for differentiation among (but not within) physically isolated regions in the south, including Iberia. In those regions we find evidence for a stronger influence from natural processes than may be expected for a species with such strong, known anthropogenic influence.
Data from: Disentangling the pathways of land use impacts on the functional structure of fish assemblages in Amazon streams
Agricultural land use is a primary driver of environmental impacts on streams. However, the causal processes that shape these impacts operate through multiple pathways and at several spatial scales. This complexity undermines the development of more effective management approaches, and illustrates the need for more in-depth studies to assess the mechanisms that determine changes in stream biodiversity. Here we present results of the most comprehensive multi-scale assessment of the biological condition of streams in the Amazon to date, examining functional responses of fish assemblages to land use. We sampled fish assemblages from two large human-modified regions, and characterized stream conditions by physical habitat attributes and key landscape-change variables, including density of road crossings (i.e. riverscape fragmentation), deforestation, and agricultural intensification. Fish species were functionally characterized using ecomorphological traits describing feeding, locomotion, and habitat preferences, and these traits were used to derive indices that quantitatively describe the functional structure of the assemblages. Using structural equation modeling, we disentangled multiple drivers operating at different spatial scales, identifying causal pathways that significantly affect stream condition and the structure of the fish assemblages. Deforestation at catchment and riparian network scales altered the channel morphology and the stream bottom structure, changing the functional identity of assemblages. Local deforestation reduced the functional evenness of assemblages (i.e. increased dominance of specific trait combinations) mediated by expansion of aquatic vegetation cover. Riverscape fragmentation reduced functional richness, evenness and divergence, suggesting a trend toward functional homogenization and a reduced range of ecological niches within assemblages following the loss of regional connectivity. These results underscore the often-unrecognized importance of different land use changes, each of which can have marked effects on stream biodiversity. We draw on the relationships observed herein to suggest priorities for the improved management of stream systems in the multiple-use landscapes that predominate in human-modified tropical forests.
Data from: Population structure of the invasive forest pathogen Hymenoscyphus pseudoalbidus
Understanding the genetic diversity and structure of invasive pathogens in source and introduced areas is crucial to reveal hidden biological aspects of an organism, to reconstruct the course of invasions and to establish effective control measures. Hymenoscyphus pseudoalbidus (anamorph: Chalara fraxinea) is an invasive and highly destructive fungal pathogen on common ash Fraxinus excelsior in Europe and occurs natively in east Asia. To get insights into the dispersal mechanism and the history of invasion, we used microsatellite markers and characterized the genetic structure and diversity of H. pseudoalbidus populations at three spatial levels: (i) in Europe; (ii) at the epidemic front and (iii) between Europe and Japan. The 1208 European strains form one large population as no evident structure was detected using Bayesian and multivariate clustering analysis. Only the distribution of genetic diversity in space, pairwise population differentiation (GST) and the spatial analysis of principal components revealed a faint geographic pattern around Europe. A significant allele deficiency in most European populations pointed to a recent genetic bottleneck whereas no pattern of isolation by distance was found. Populations from Japan harbored a higher genetic diversity and were genetically differentiated from European ones. Nevertheless, phylogenetic and network analysis clearly demonstrated that individuals from both regions are conspecific. Our data suggest that H. pseudoalbidus was introduced only once by a minimum of two individuals. The potential source region of H. pseudoalbidus is huge and further investigations are required for a more accurate localization of the source population.
Data from: Mitochondrial genetic structure and matrilineal origin of white sharks, Carcharodon carcharias, in the Northeastern Pacific: implications for their conservation
White sharks (Carcharodon carcharias, WS henceforth) are globally and regionally threatened. Understanding their patterns of abundance and connectivity, as they relate to habitat use, is central for delineating conservation units and identifying priority areas for conservation. We analyzed mitochondrial data to test the congruence between patterns of genetic connectivity and of individual movements in the Northeastern Pacific (NEP) and to trace the matrilineal origin of immature WS from coastal California and Baja California to adult aggregation areas. We analyzed 186 mitochondrial control region sequences from sharks sampled in Central California (CC; n = 61), Southern California Bight (SCB; n = 25), Baja California Pacific coast (BCPC; n = 9), Bahía Vizcaíno (BV; n = 39), Guadalupe Island (GI; n = 45), and the Gulf of California (GC; n = 7). Significant mitochondrial differentiation between adult aggregation areas (CC, GI) revealed two reproductive populations in the NEP. We found general concordance between movement patterns of young and adult WS with genetic results. Young sharks from coastal California and Baja California were more likely born from females from GI. Mitochondrial differentiation of young-of-the-year from SCB and BV suggests philopatry to nursery areas in females from GI. These results provide a genetic basis of female reproductive behavior at a regional scale and point to a preponderance of sharks from GI in the use of the sampled coastal region as pupping habitat. These findings should be considered in Mexican and US management and conservation strategies of the WS NEP population.
Data from: Landscape genomics of Populus trichocarpa: the role of hybridization, limited gene flow and natural selection in shaping patterns of population structure
Populus trichocarpa is an ecologically important tree across western North America. We used a large population sample of 498 accessions over a wide geographical area genotyped with a 34K Populus SNP array to quantify geographical patterns of genetic variation in this species (landscape genomics). We present evidence that three processes contribute to the observed patterns: (1) introgression from the sister species P. balsamifera (2) isolation-by-distance and (3) natural selection. Introgression was detected only at the margins of the species' distribution. Isolation-by-distance was significant across the sampled area as a whole, but no evidence of restricted gene flow was detected in a core of drainages from southern British Columbia. We identified a large number of FST outliers. GO analyses revealed that FST outliers are overrepresented in genes involved in circadian rhythm and response to red/far-red light when the entire dataset is considered, while in southern British Columbia heat response genes are overrepresented. We also identified strong correlations between geoclimate variables and allele frequencies at FST outlier loci that provide clues regarding the selective pressures acting at these loci.
Data from: Naturalized distributions show that climatic disequilibrium is structured by niche size in pines (Pinus L.)
Aim: The assumption that species' native distributions are in equilibrium with climate has been shown to be frequently violated, despite its centrality to many niche model applications. We currently lack a framework that predicts these violations. Here we examine whether variation in climatic disequilibrium is structured by properties of species' native distributions and climatic niches. Location: Global Methods: We built climatic niche models for 106 pine (Pinus L.) species, including 25 that have naturalized outside their native range. We measured the extent of climate space occupied exclusively by naturalized populations and considered what fraction of this space was available within the native continent and near the native range. We examined the consequences of disequilibrium for estimates of potential range filling and sister-species niche conservatism. Results: Most species (23 of 25) have naturalized in climate conditions outside of the native niche, leading to increases in the total known suitable climate space. Increases in niche size were negatively related to native niche size. Increases were often large – one species expanded its niche by almost 10% of the global climate space. These increases were associated primarily with cooler, wetter, and less seasonal climates. Increases in known niche size lowered potential range filling estimates within species' native continent and ecoregion. Naturalized data did not strengthen support for niche conservatism among sister species. Main Conclusions: Among pines, climatic disequilibrium is the norm and not the exception. The magnitude of this disequilibrium can be vast, such that the native range greatly underrepresents the true climatic tolerances of some species. Fortunately, this disequilibrium can largely be predicted by the size of a species' native niche. Accounting for this disequilibrium can improve our ability to characterize ecological phenomena, including potential range filling. This is an essential step toward improving the conservation value of ecological niche models.
Data from: Is population structure in the European white stork determined by flyway permeability rather than translocation history?
European white stork are long considered to diverge to eastern and western migration pools as a result of independent overwintering flyways. In relatively recent times, the western and northern distribution has been subject to dramatic population declines and country-specific extirpations. A number of independent reintroduction programs were started in the mid 1950s to bring storks back to historical ranges. Founder individuals were sourced opportunistically from the Eastern and Western European distributions and Algeria, leading to significant artificial mixing between eastern and western flyways. Here we use mitochondrial and microsatellite DNA to test the contention that prior to translocation, eastern and western flyways were genetically distinct. The data show a surprising lack of structure at any spatial or temporal scale suggesting that even though birds were moved between flyways, there is evidence of natural mixing prior to the onset of translocation activities. Overall a high retention of genetic diversity, high Nef, and an apparent absence of recent genetic bottleneck associated with early 20th century declines suggest that the species is well equipped to respond to future environmental pressures.
Data from: Impact of habitat fragmentation on the spatial structure of the Eastern Arc Forests in East Africa: implications for biodiversity conservation
The Eastern Arc Mountains in Tanzania and Kenya are one of 35 global biodiversity hotspots. The Eastern Arc forests are, as are many other tropical biodiversity hotspots, highly fragmented. Understanding the impact of habitat fragmentation (i.e., habitat loss and subdivision) on the spatial structure of the Eastern Arc forests is important because forest spatial structure highly influences species richness, persistence, and extinction debt. Here we examine the impact of habitat fragmentation on the spatial structure of the Eastern Arc forests at a patch scale using very high resolution aerial imagery having a spatial resolution of 0.5–1.5 m. Forest area across the 13 Eastern Arc Mountains is 405,852 ha and is distributed into 311 fragments ≥ 10 ha in size with a median fragment size of 84 ha. The 18 largest forest fragments in the Eastern Arc Mountains contain greater than three-quarters of total forest area. Average fragment isolation, as assessed by median distance to nearest fragment and median distance to the nearest larger fragment, is 867 and 1533 m, respectively. Of total forest area, 14% is < 100 m from the forest edge and 33% is < 300 m from the forest edge. Establishing forested linkages among the largest and closest forest fragments through forest regeneration and protection of secondary regenerating forest as well as providing protected area status to the remaining non-protected forest including unprotected smaller forest fragments are important to enhancing the long-term persistence of many plant and animal species here.
Data from: Quantifying floristic and structural forest maturity: an attribute-based method for wet eucalypt forests
1. Maintaining developmental heterogeneity of ecological communities within landscapes is crucial for sustainable native forest management. Consequently, methods to assess forest maturity (i.e. the degree to which the forest contains attributes and supports processes characteristic of late-successional forests) are valuable for making management decisions. However, no consistent, pragmatic method to quantify maturity that incorporates multiple ecosystem elements is available for many forest systems, including Australian wet eucalypt forests. 2. We draw upon forest community dynamics theory to develop a method to quantify maturity based on forest attributes, and use this method to create two metrics of wet eucalypt forest floristic and structural maturity. We then test the ability of remotely-sensed and field-collected variables to predict these metrics. 3. Both the floristic and structural maturity metrics performed well at capturing underlying trends of forest maturation. Remotely-sensed LiDAR (Light Detection and Ranging) and photo-interpretation data provided estimates of moderate accuracy for both floristic and structural maturity (R2 = 0.57-0.77). Field variables that are relatively efficient and accurate to measure provided greater model accuracy (R2 = 0.73-0.85). Including more complex field variables increased model accuracy to high levels (R2 = 0.93). Therefore, while maturity predicted from remote-sensing data enables a useful and accessible large-scale maturity measure, field indices would provide a more accurate means of assessing maturity at the local stand level. 4. Synthesis and applications: The metrics developed in this study provide a powerful tool for undertaking consistent assessments of wet eucalypt forest maturity. This assessment tool could improve forest management by providing information to optimise practices such as prioritising stands for retention or harvesting, determining the effectiveness of restoration or management practices, and monitoring changes in maturity over time. The method could be adapted to any forest system that undergoes well-defined directional development.
Data from: Phylogeography of African locust bean (Parkia biglobosa) reveals genetic divergence and spatially structured populations in West and Central Africa
The evolutionary history of African savannah tree species is crucial for the management of their genetic resources. In this study, we investigated the phylogeography of Parkia biglobosa and its modelled distribution under past and present climate conditions. This tree species is very valued and widespread in West Africa, providing edible and medicinal products. A large sample of 1 610 individuals from 84 populations, distributed across 12 countries in Western and Central Africa, were genotyped using eight nuclear microsatellites. Individual-based assignments clearly distinguished three genetic clusters, extreme West Africa (EWA), centre of West Africa CWA), and Central Africa (CA). Overall, estimates of genetic diversity were moderate to high, with lower values for populations in EWA (AR=6.4, HE=0.78 and HO=0.7) and CA (AR=5.9, HE=0.67 and HO=0.61) compared to populations in CWA (AR=7.3, HE=0.79 and HO=0.75). The overall population differentiation was found to be moderate (FST=0.09). A highly significant isolation-by-distance pattern was detected, with a marked phylogeographic signature suggesting possible effects of past climate and geographic barriers to migration. Modelling the potential distribution of the species showed a contraction during the last glaciations followed by expansion events. The exploratory Approximate Bayesian Computation conducted suggests a best-supported scenario in which the cluster CWA traced back to the ancestral populations and a first split between EWA and CWA took place about 160 000 years BP, then a second split divided CA and CWA, about 100 000 years BP. However, our genetic data do not enable to conclusively distinguish among a few alternative possible scenarios.
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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.