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Data from: Comparing cal3 and other a posteriori time-scaling approaches in a case study with the pterocephaliid trilobites
Reconstructing the tree of life involves more than identifying relationships among lineages; it also entails accurately estimating when lineages diverged. Paleontologists typically scale cladograms to time a posteriori by direct reference to first appearances of taxa in the stratigraphic record. Some approaches use probabilistic models of branching, extinction, and sampling processes to date samples of trees, such as the recently developed cal3 method, which stochastically draws divergence dates given a set of rates for those processes. However, these models require estimates of the rates of those processes, which may be hard to obtain, particularly for sampling. Here, we contrast the use of cal3 and other a posteriori time-scaling approaches by examining a previous study that documented a decelerating rate of morphological evolution in pterocephaliid trilobites. Although aspects of the data set make estimation of branching, extinction, and sampling rates difficult, we use a multifaceted approach to calculate and evaluate the rate estimates needed for applying cal3. In agreement with previous simulation studies, we find that the choice of phylogenetic dating method impacts downstream macroevolutionary conclusions. We also find contradictory evolutionary inferences between analyses on ancestor–descendant contrasts (based on ancestor trait reconstruction methods) and maximum-likelihood parameter estimates. Ancestral taxon inference in cal3 corroborates previously hypothesized ancestor–descendant sequences, but cal3 suggests greater support for budding cladogenesis than anagenesis. This case study demonstrates the potential and wide applicability of the cal3 method and the benefits afforded by choosing cal3 over simpler a posteriori time-scaling approaches.
Data from: Comparative analysis of DNA extraction methods to study the body surface microbiota of insects: a case study with ant cuticular bacteria
High-throughput sequencing of the 16S rRNA gene has considerably helped revealing the essential role of bacteria living on insect cuticles in the ecophysiology and behavior of their hosts. However, our understanding of host-cuticular microbiota feedbacks remains hampered by the difficulties to working with low bacterial DNA quantities as in individual insect cuticle samples, which are more prone to molecular biases and contaminations. Herein, we conducted a methodological benchmark on the cuticular bacterial loads retrieved from two Neotropical ant species of different body size and ecology: Atta cephalotes (~15 mm) and Pseudomyrmex penetrator (~5 mm). We evaluated the richness and composition of the cuticular microbiota, as well as the amount of biases and contamination produced by four DNA extraction protocols. We also addressed how bacterial communities' characteristics would be affected by the number of individuals or individual body size used for DNA extraction. Most extraction methods yielded similar results in term of bacterial diversity and composition for A. cephalotes (~15 mm). In contrast, greater amounts of artifactual sequences and contaminations, as well as noticeable differences in bacterial communities' characteristics were observed between the extraction methods for P. penetrator (~5 mm). We also found that large (~15 mm) and small (~5 mm) A. cephalotes individuals harbor different bacterial communities. Our benchmark hence suggests that cuticular microbiota of single insect individuals can be reliably retrieved provided that blank controls, appropriate data cleaning, and standardization of individual body size are considered in the experiment.
Data from: Identifying spawning sites and other critical habitat in lotic systems using eDNA "snapshots": a case study using the sea lamprey Petromyzon marinus L.
Many aquatic species of conservation concern exist at low densities and are inherently difficult to detect or monitor using conventional methods. However, the introduction of environmental (e)DNA has recently transformed our ability to detect these species and enables effective deployment of limited conservation resources. Identifying areas for breeding, as well as the ecological distribution of a species are vital to the survival or recovery of a conservation species (i.e. critical habitat). In many species, spawning events are associated with a higher relative abundance of DNA released within an aquatic system (i.e. gametes, skin cells etc.), making this the ideal time to monitor these species using eDNA techniques. This study aims to examine whether a 'snapshot' eDNA sampling approach (i.e. samples taken at fixed points in chronological time) could reveal areas of critical habitat including spawning sites for our target species Petromyzon marinus. We utilised a species-specific qPCR assay to monitor spatial and temporal patterns in eDNA concentration within two river catchments in Ireland over three consecutive years. We found that eDNA concentration increased at the onset of observed spawning activity and patterns of concentration increased from downstream to upstream over time, suggesting dispersal into the higher reaches as the spawning season progressed. We found P. marinus to be present upstream of several potential barriers to migration, sometimes in significant numbers. Out results also show that the addition of lamprey-specific fish-pass at an 'impassable' weir, although assisting in ascent, did not have any significant impact on eDNA concentration upstream after pass had been installed. eDNA concentration was also found to be significantly correlated with both the number of fish and the number of nests encountered. The application of snapshot sampling techniques for species monitoring therefore has substantial potential for the management of low-density species in fast-moving aquatic systems.
Data from: Temporal dynamics of encrusting communities during the Late Devonian: a case study from the Central Devonian Field, Russia
In this study we focused on the dynamics of encrusting assemblages preserved on brachiopod hosts collected from upper Frasnian and lower Famennian deposits of the Central Devonian Field, Russia. Because the encrusted brachiopods come from deposits bracketing the Frasnian/Famennian (F/F) boundary, the results also shed some light on ecological differences in encrusting communities before and after the Frasnian–Famennian (F-F) event. To explore the diversity dynamics of encrusting assemblages, we analyzed more than 1300 brachiopod valves (substrates) from two localities. Taxon accumulation plots and shareholder quorum subsampling (SQS) routines indicated that a reasonably small sample of brachiopod host valves (n=50) is sufficient to capture the majority of the encrusting genera recorded at a given site. The richness of encrusters per substrate declined simultaneously with the number of encrusting taxa in the lower Famennian, accompanied by a decrease in epibiont abundance, with a comparable decrease in mean encrustation intensity (percentage of bioclasts encrusted by one or more epibionts). Epibiont abundance and occupancy roughly mirror each other. Strikingly, few ecological characteristics are correlated with substrate size, possibly reflecting random settlement of larvae. Evenness, which is negatively correlated with substrate size, shows greater within-stage variability among samples than between Frasnian and Famennian intervals and may indicate the instability of early Famennian biocenoses following the faunal turnover. The occurrence distribution of encrusters points to nonrandom associations and exclusions among several encrusting taxa. However, abundance and occupancy of microconchids remained relatively stable throughout the sampled time interval. The notable decline in abundance (~60%) and relatively minor decline in diversity (~30%) suggest jointly that encrusting communities experienced ecological collapse rather than a major mass extinction event. The differences between the upper Frasnian and lower Famennian encrusting assemblages may thus record a turnover associated with the F-F event.
Data from: The walking dead: blender as a tool for palaeontologists with a case study on extinct arachnids
This paper serves two roles. First, it acts as an introduction to Blender, an open-source computer graphics program, which can be of utility to paleontologists. To lessen the software's otherwise steep learning curve, a step-by-step guide to create an idealized reconstruction of a fossil in the form of a three-dimensional model in Blender, or to use the software to render results from 'virtual paleontology' techniques, is provided as an online supplemental data file. Second, here we demonstrate the use of Blender with a case study on the extinct trigonotarbid arachnids. We report the limb articulations of members of the Devonian genus Palaeocharinus on the basis of exceptionally preserved fossils from the Rhynie Cherts of Scotland. We use these newly reported articulations to create a Blender model, and draw comparisons with the gait of extant arachnids to produce as accurate a representation of the trigonotarbid flexing its limbs and walking as possible, presented in additional online supplemental data files. Knowledge of the limb articulations of trigonotarbid arachnids also allows us to discuss their functional morphology: trigonotarbids' limbs and gait were likely comparable to extant cursorial spiders, but lacked some innovations seen in more derived arachnids.
Data from: Hypotheses and tracking results about the longest migration: the case of the arctic tern
The arctic tern Sterna paradisaea completes the longest known annual return migration on Earth, travelling between breeding sites in the northern arctic and temperate regions and survival/moult areas in the Antarctic pack ice zone. Salomonsen (1967) put forward a hypothetical comprehensive interpretation of this global migration pattern, suggesting food distribution, wind patterns, sea ice distribution and moult habits as key ecological and evolutionary determinants. We used light-level geolocators to record twelve annual journeys by eight individuals of arctic terns breeding in the Baltic Sea. Migration cycles were evaluated in the light of Salomonsen's hypotheses and compared with results from geolocator studies of arctic tern populations from Greenland, Netherlands and Alaska. The Baltic terns completed a 50,000 km annual migration circuit, exploiting ocean regions of high productivity in the North Atlantic, Benguela Current and the Indian Ocean between southern Africa and Australia (sometimes including the Tasman Sea). They arrived about 1 November in the Antarctic zone at far easterly longitudes (in one case even at the Ross Sea) subsequently moving westwards across 120 – 220 degrees of longitude towards the Weddell Sea region. They departed from here in mid-March on a fast spring migration up the Atlantic Ocean. The geolocator data revealed unexpected segregation in time and space between tern populations in the same flyway. Terns from the Baltic and Netherlands travelled earlier and to significantly more easterly longitudes in the Indian Ocean and Antarctic zone than terns from Greenland. We suggest an adaptive explanation for this pattern. The global migration system of the arctic tern offers an extraordinary possibility to understand adaptive values and constraints in complex pelagic life cycles, as determined by environmental conditions (marine productivity, wind patterns, low pressure trajectories, pack ice distribution), inherent factors (flight performance, moult, flocking) as well as effects of predation/piracy and competition.
Data from: Validation of an algorithm for identifying MS cases in administrative health claims datasets
Objective: To develop a valid algorithm for identifying multiple sclerosis (MS) cases in administrative health claims (AHC) datasets. Methods: We used 4 AHC datasets from the Veterans Administration (VA), Kaiser Permanente Southern California (KPSC), Manitoba (Canada), and Saskatchewan (Canada). In the VA, KPSC, and Manitoba, we tested the performance of candidate algorithms based on inpatient, outpatient, and disease-modifying therapy (DMT) claims compared to medical records review using sensitivity, specificity, positive and negative predictive values, and interrater reliability (Youden J statistic) both overall and stratified by sex and age. In Saskatchewan, we tested the algorithms in a cohort randomly selected from the general population. Results: The preferred algorithm required ≥3 MS-related claims from any combination of inpatient, outpatient, or DMT claims within a 1-year time period; a 2-year time period provided little gain in performance. Algorithms including DMT claims performed better than those that did not. Sensitivity (86.6%–96.0%), specificity (66.7%–99.0%), positive predictive value (95.4%–99.0%), and interrater reliability (Youden J = 0.60–0.92) were generally stable across datasets and across strata. Some variation in performance in the stratified analyses was observed but largely reflected changes in the composition of the strata. In Saskatchewan, the preferred algorithm had a sensitivity of 96%, specificity of 99%, positive predictive value of 99%, and negative predictive value of 96%. Conclusions: The performance of each algorithm was remarkably consistent across datasets. The preferred algorithm required ≥3 MS-related claims from any combination of inpatient, outpatient, or DMT use within 1 year. We recommend this algorithm as the standard AHC case definition for MS.
Data from: Outcome of breast cancer in Moroccan young women correlated to clinic-pathological features, risk factors and treatment: a comparative study of 716 cases in a single institution
Background: Breast cancer in young women is quite uncommon and shows more aggressive characteristics with major disparities between worldwide populations. Prognosis and outcome of breast cancer in young patients are widely studied, but still no consensus is available. Methods: We retrospectively included 716 cases of breast cancer women diagnosed in 2009 at the National Institute of Oncology of Rabat. Patients were divided into two groups according to their age: women aged ≤40 years (Group 1) and women aged >40 years (Group 2). Data were recorded from patients' medical files and analyzed using SPSS 13.0 software (IBM). Results: Young patients represent 24.9% of all patients with breast cancer. The comparison between the two groups displayed significant differences regarding nulliparity (p = 0.001) and progesterone receptor negativity (p = 0.01). Moreover, more progression (Metastases/Relapse) was registered in young women as compared to older women with breast cancer (p = 0.03). The estimated median follow-up period was 31 months. The 5-years Event-Free Survival (EFS) of patients with local disease was 64.6% in young women and 71.5% in older women with breast cancer (p = 0.04). Multivariate analysis in young women showed that nulliparity (HR: 7.2; 95%CI: 1.16–44.54; p = 0.03), T3 tumors (HR: 17.39; 95%CI: 1.74–173.34; p = 0.01) and negative PgR status (HR: 19.85; 95%CI: 1.07–366.54; p = 0.04) can be considered as risk factors for poorer event free survival while hormone therapy was associated with better EFS (HR: 0.11; 95%CI: 0.00–0.75; p = 0.03). In Group 2, multivariate analysis showed that patients with inflammatory breast cancer, N+ status, absence of radiotherapy, absence of chemotherapy, and absence of hormone therapy are at increased risk of recurrence. Conclusions: In Morocco, breast cancer is more frequent in young women as compared to western countries. Breast cancer in young women is more aggressive and is diagnosed late, leading to an intensive treatment. Moreover, the main factors associated with breast cancer development in young women would be hormonal and reproductive status. Analysis of other genetic biomarkers is needed to explain the high prevalence of breast cancer in young women to improve breast cancer management in Morocco
Data from: On the accuracy of paleodiversity reconstructions: a case study in Antarctic Neogene radiolarians
The deep-sea Cenozoic planktonic microfossil record has the unique characteristics of continuously well-preserved populations of most species, with virtually unlimited sample size, and therefore constitutes, in principle, a major resource for macroevolutionary research. Antarctic Neogene radiolarians in particular, are diverse, abundant and consistently well-preserved and evolved rapidly. This fauna is, in theory, a near-perfect testing ground for paleodiversity reconstructions. In this study we determined the diversity history of these faunas from a new quantitative, taxonomically complete data set from Neogene and Quaternary sections at several Antarctic sites. The pattern retrieved by our whole-fauna data set shows a significant, largely extinctionless ecological change in faunal composition and decrease in the evenness of species' abundances during the late Miocene, followed 3 Myr later, at around 5 Ma, by a significant drop in diversity. We tentatively associate this ecological event with a synchronous, regional change in the composition of the primary producers, but as yet cannot identify any environmental changes associated with the later extinction. Further, our whole-fauna diversity history was compared to diversity computed from much less complete, biostratigraphically oriented studies of species' occurrences, compiled in the Neptune database and reconstructed by using subsampling methodologies. Comparison of our whole-fauna and subsampling-reconstructed diversity patterns shows that the first-order trends are the same in both, suggesting that, to some degree, such literature compilations can be used to explore diversity history of plankton. However, our results also highlight substantial errors and distortions in the reconstructed diversity which make it poorly suited to more-detailed studies (e.g., for comparison of diversity history with paleoenvironmental history). We conclude that detailed studies of plankton diversity, and particularly those attempting to understand the relation between diversity and paleoceanographic change, should be based on taxonomically comprehensive, quantitative data.
Data from: eDNA surveys to detect species at very low densities: a case study of European carp eradication in Tasmania, Australia
1. Eradications of invasive species are usually expensive and difficult to conduct. Knowing when to declare an eradication successful requires distinguishing between failed detection of the target species due to imperfect sensitivity of the detection method and true species absence. This is difficult because the sensitivities of many detection methods are unknown. 2. Environmental DNA (eDNA) methods can be used to detect species by analysing DNA present in environmental samples. eDNA has been promoted as a particularly sensitive and cost-effective way to detect species at low densities and, importantly, the sensitivity of eDNA surveys can be quantified. Nevertheless, the effort and costs involved in detecting species at extremely low densities, such as required during eradication, have not been previously calculated. 3. We evaluated the sensitivity of eDNA surveys in detecting the invasive European carp, Cyprinus carpio, in two lakes in Tasmania, Australia, one in which carp have been eradicated and a second in which carp are currently being eradicated. We determined the sampling effort and associated cost required to detect the species at very low density in these lakes. 4. While our eDNA survey detected the current low density carp population present in in Lake Sorell, we show that an exponential increase in sampling effort and associated cost will be required to confidently detect the species as the population declines. Similarly, while our eDNA survey corroborated the species absence from Lake Crescent, our detection confidence was low. We quantify the survey effort and financial investment required to confidently establish eradication success in Lake Crescent. Synthesis and applications: 5. Estimating the eDNA survey effort and cost required to detect species at a given density will enable practitioners to make informed decisions on the feasibility of implementing such surveys. Quantifying the sensitivity of eDNA surveys will also inform the confidence practitioners should place in the results of eDNA detection surveys to ensure appropriate management actions are implemented and provide a suitable stopping point at which to confidently declare eradication success.09-Jul-2019
Data from: A parallel population genomic and hydrodynamic approach to fishery management of highly-dispersive marine invertebrates: the case of the Fijian black-lip pearl oyster Pinctada margaritifera
Fishery management and conservation of marine species increasingly relies on genetic data to delineate biologically relevant stock boundaries. Unfortunately for high gene flow species which may display low, but statistically significant population structure, there is no clear consensus on the level of differentiation required to resolve distinct stocks. The use of fine-scale neutral and adaptive variation, considered together with environmental data can offer additional insights to this problem. Genome-wide genetic data (4,123 SNPs), together with an independent hydrodynamic particle dispersal model were used to inform farm and fishery management in the Fijian black-lip pearl oyster Pinctada margaritifera, where comprehensive fishery management is lacking, and the sustainability of exploitation uncertain. Weak fine-scale patterns of population structure were detected, indicative of broad-scale panmixia among wild oysters, while a hatchery-sourced farmed population exhibited a higher degree of genetic divergence (Fst = 0.0850–0.102). This hatchery-produced population had also experienced a bottleneck (NeLD = 5.1; 95% C.I. = [5.1–5.3]); compared to infinite NeLD estimates for all wild oysters. Simulation of larval transport pathways confirmed the existence of broad-scale mixture by surface ocean currents, correlating well with fine-scale patterns of population structuring. Fst outlier tests failed to detect large numbers of loci supportive of selection, with 2–5 directional outlier SNPs identified (average Fst = 0.116). The lack of biologically significant population genetic structure, absence of evidence for local adaptation and larval dispersal simulation, all indicate the existence of a single genetic stock of P. margaritifera in the Fiji Islands. This approach using independent genomic and oceanographic tools has allowed fundamental insights into stock structure in this species, with transferability to other highly-dispersive marine taxa for their conservation and management.
Data from: Comparative analyses of effective population size within and among species: ranid frogs as a case study
It has recently become practicable to estimate the effective sizes (Ne) of multiple populations within species. Such efforts are valuable for estimating Ne in evolutionary modeling and conservation planning. We used microsatellite loci to estimate Ne of 90 populations of four ranid frogs (20 to 26 populations per species, mean n per population = 29). Our objectives were to determine typical values of Ne for populations of each species, compare Ne estimates among the species, and test for correlations between several geographic variables and Ne within species. We used single-sample linkage disequilibrium, approximate Bayesian computation, and sibship assignment methods to estimate contemporary Ne for each population. Three of the species—Rana pretiosa, R. luteiventris, and R. cascadae— have consistently small effective population sizes (<50). Ne in Lithobates pipiens spans a wider range, with some values in the hundreds or thousands. There is a strong east-to-west trend of decreasing Ne in Lithobates pipiens. The smaller effective sizes of western populations of this species may be related to habitat fragmentation and population bottlenecking.
Data from: Mating system and genetic diversity of progenies before and after logging: a case study of Bagassa guianensis (Moraceae), a low-density dioecious tree of the Amazonian forest
The logging of large trees in tropical forests causes a decrease in the density of reproductive individuals, which likely affects the pattern of pollen dispersal and the mating system of the remaining trees in the population. Here, we investigate the impact of logging on mating system and genetic diversity of the low-density, thrip-pollinated, dioecious tree Bagassa guianensis within a 500-ha plot at Tapajós National Forest, Pará State, Brazil. Mating system parameters of the logged population were estimated using mixed-mating model. Six microsatellite loci were used to genotype 232 seeds from ten remnant female trees over three seasons (2006, 2007, and 2008). The data were compared with the mating system of the unlogged population of B. guianensis (18 female trees, 488 seeds) in the same plot. The overall number of alleles found in the open-pollinated progenies decreased after logging (K = 71 before logging and K = 57 after logging, considering the three after logging seasons pooled), as well as the average number of alleles per locus (A = 11.8 and 9.5, respectively). Similarly, the number of private alleles, which is defined in the context of this study as the number of alleles observed in the population exclusively before or after logging, also decreased after logging (15 and 1, respectively). However, the average number of alleles per locus and the observed and expected heterozygosities were not significantly higher before logging than after logging. Logging also did not affect the inbreeding of progenies in the population. Somewhat unexpectedly, the effective number of pollen donors was consistently higher after (N ep = 14.5 in 2006, 8.1 in 2007, and 6.3 in 2008) than before logging (N ep = 3.4), suggesting that the loss of alleles in the population was compensated by the higher heterogeneity in the pollen pool after the removal of the largest trees by logging. Potential causes explaining the patterns found here include the maintenance of large patches of forest around the logged plot and the species' ability to perform long-distance pollination by airborne thrips. Maintenance of landscape integrity as logged and unlogged forests around the exploited areas is recommended to enhance pollen migration and to avoid long-term losses in genetic diversity.
Data from: Longevity and transposon defense, the case of termite reproductives
Social insects are promising new models in aging research. Within single colonies, longevity differences of several magnitudes exist that can be found elsewhere only between different species. Reproducing queens (and, in termites, also kings) can live for several decades, whereas sterile workers often have a lifespan of a few weeks only. We studied aging in the wild in a highly social insect, the termite Macrotermes bellicosus, which has one of the most pronounced longevity differences between reproductives and workers. We show that gene-expression patterns differed little between young and old reproductives, implying negligible aging. By contrast, old major workers had many genes up-regulated that are related to transposable elements (TEs), which can cause aging. Strikingly, genes from the PIWI-interacting RNA (piRNA) pathway, which are generally known to silence TEs in the germline of multicellular animals, were down-regulated only in old major workers but not in reproductives. Continued up-regulation of the piRNA defense commonly found in the germline of animals can explain the long life of termite reproductives, implying somatic cooption of germline defense during social evolution. This presents a striking germline/soma analogy as envisioned by the superorganism concept: the reproductives and workers of a colony reflect the germline and soma of multicellular animals, respectively. Our results provide support for the disposable soma theory of aging.
Data from: Genetic assignment with isotopes and habitat suitability (GAIAH), a migratory bird case study
1. Identifying migratory connections across the annual cycle is important for studies of migrant ecology, evolution, and conservation. While recent studies have demonstrated the utility of high-resolution SNP-based genetic markers for identifying population-specific migratory patterns, the accuracy of this approach relative to other intrinsic tagging techniques has not yet been assessed. 2. Here, using a straightforward application of Bayes' Rule, we develop a method for combining inferences from high-resolution genetic markers, stable isotopes, and habitat suitability models, to spatially infer the breeding origin of migrants captured anywhere along their migratory pathway. Using leave-one-out cross validation, we compare the accuracy of this combined approach with the accuracy attained using each source of data independently. 3. Our results indicate that when each method is considered in isolation, the accuracy of genetic assignments far exceeded that of assignments based on stable isotopes or habitat suitability models. However, our joint assignment method consistently resulted in small, but informative increases in accuracy and did help to correct misassignments based on genetic data alone. We demonstrate the utility of the combined method by identifying previously undetectable patterns in the timing of migration in a North American migratory songbird, the Wilson's warbler. 4. Overall, our results support the idea that while genetic data provides the most accurate method for tracking animals using intrinsic markers when each method is considered independently, there is value in combining all three methods. The resulting methods are provided as part of a new computationally-efficient R-package, GAIAH, allowing broad application of our statistical framework to other migratory animal systems.
Data from: Examining the business case and models for sustainable multifunctional edible landscaping enterprises in the Phoenix Metro Area
This study assesses whether multifunctional edible landscaping business models provide a sufficient business case at enterprise and city scales to justify widespread implementation. First, semi-structured interviews were conducted with four landscaping entrepreneurs, and the information obtained from the interviews was utilized to carry out a business model comparison with the Business Model Canvas framework. The comparison showed that the landscaping enterprises using multifunctional edible landscaping methods possessed a greater range of value propositions and revenue streams, enhancing their competitive advantage. Second, a GIS landscape analysis of seven Phoenix metro area cities was carried out to identify landscapes that were suited for becoming multifunctional edible landscapes. The GIS analysis identified single family residential, residential recreational open space, municipal parks, and municipal schools as being suitable landscapes, and that the area of these landscapes in the seven cities exceeded 180,000 acres. Third, scenarios were created using interview and GIS data to estimate potential value creation and return on investment of implementing multifunctional edible landscaping in the cities of interest. The scenarios found that the potential value creation of edible landscaping ranged between $3.9 and $66 billion, and that positive return on investment (ROI) could be achieved in 11 out of 12 scenarios within one to five years. Finally, the paper concludes by discussing potential long-term implications of implementing multifunctional edible urban landscaping, as well as possible future directions for multifunctional landscaping business model development and research.
Data from: The impact of climate change on the potential distribution of agricultural pests: the case of the coffee white stem borer (Monochamus leuconotus P.) in Zimbabwe
The production of agricultural commodities faces increased risk of pests, diseases and other stresses due to climate change and variability. This study assesses the potential distribution of agricultural pests under projected climatic scenarios using evidence from the African coffee white stem borer (CWB), Monochamus leuconotus (Pascoe) (Coleoptera: Cerambycidae), an important pest of coffee in Zimbabwe. A species distribution modeling approach utilising Boosted Regression Trees (BRT) and Generalized Linear Models (GLM) was applied on current and projected climate data obtained from the WorldClim database and occurrence data (presence and absence) collected through on-farm biological surveys in Chipinge, Chimanimani, Mutare and Mutasa districts in Zimbabwe. Results from both the BRT and GLM indicate that precipitation-related variables are more important in determining species range for the CWB than temperature related variables. The CWB has extensive potential habitats in all coffee areas with Mutasa district having the largest model average area suitable for CWB under current and projected climatic conditions. Habitat ranges for CWB will increase under future climate scenarios for Chipinge, Chimanimani and Mutare districts while it will decrease in Mutasa district. The highest percentage change in area suitable for the CWB was for Chimanimani district with a model average of 49.1% (3 906 ha) increase in CWB range by 2080. The BRT and GLM predictions gave similar predicted ranges for Chipinge, Chimanimani and Mutasa districts compared to the high variation in current and projected habitat area for CWB in Mutare district. The study concludes that suitable area for CWB will increase significantly in Zimbabwe due to climate change and there is need to develop adaptation mechanisms.
Highlighting convergent evolution in morphological traits in response to climatic gradient in African tropical tree species: the case of genus Guibourtia Benn
<ol> <li><span>Adaptive evolution is a major driver of organism diversification but the links between phenotypic traits and environmental niche remains little documented in tropical trees. Moreover, trait-niche relationships are complex because a correlation between the traits and environmental niches displayed by a sample of species may result from (1) convergent evolution if different environmental conditions have selected different sets of traits, and/or (2) phylogenetic inertia if niche and morphological differences between species are simply function of their phylogenetic divergence, in which case the trait-niche correlation does not imply any direct causal link. Here, we aim to assess the respective roles of phylogenetic inertia and convergent evolution in shaping the differences of botanical traits and environmental niches among congeneric African tree species that evolved in different biomes. </span></li> <li><span>This issue was addressed with the tree genus <i>Guibourtia </i>Benn. (Leguminosae, Detarioideae) which contains 13 African species occupying various forest habitat types, from rain forest to dry woodlands, with different climate and soil conditions. To this end, we combined morphological data with ecological niche modelling and used a highly resolved plastid phylogeny of the 13 African <i>Guibourtia</i> species. </span></li> <li><span>First, we demonstrated phylogenetic signals in both morphological traits (Mantel test between phylogenetic and morphological distances between species: r=0.24, p=0.031) and environmental niches (Mantel test between phylogenetic and niche distances between species: r=0.23, p=0.025). Second, we found a significant correlation between morphology and niche, at least between some of their respective dimensions (Mantel's r=0.32, p=0.013), even after accounting for phylogenetic inertia (Phylogenetic Independent Contrast: r=0.69, p=0.018). This correlation occurred between some leaflet and flower traits and solar radiation, relative humidity, precipitations and temperature range. </span></li> <li><span>Our results demonstrate the convergent evolution of some morphological traits in response to climatic factors in congeneric tree species and highlight the action of selective forces, along with neutral ones, in shaping the divergence between congeneric tropical plants.</span></li> </ol>
Data from: Competition in slow motion: the unusual case of benthic marine communities in the wake of the end-Permian mass extinction
Changes of community structure in response to competition usually take place on timescales that are much too short to be visible in the geological record. Here we report the notable exception of a benthic marine community in the wake of the end-Permian mass extinction, which is associated with the microbial limestone facies of the earliest Triassic of South China. The newly reported fauna is well preserved and extraordinarily rich (30 benthic macroinvertebrate species, including the new species Astartella? stefaniae (Bivalvia) and Eucochlis obliquecostata (Gastropoda)) and stems from an environmentally stable setting providing favourable conditions for benthic organisms. Whereas changes in the taxonomic composition are negligible over the observed time interval of 10–100 ka, three ecological stages are identified, in which relative abundances of initially rare species continuously increased at the cost of previously dominant species. Concomitant with the changes of dominant species is an increase in faunal evenness and heterogeneity. In the absence of both environmental and taxonomic changes, we attribute this pattern to the long-term effects of interspecific competition, which acted at an unusually slow pace because the number of competing species and potential immigrants was dramatically reduced by the end-Permian mass extinction. We suggest that these non-actualistic conditions led to decreased rates of niche differentiation and hence to the delayed rediversification of benthos that characterizes the aftermath of the greatest Phanerozoic mass extinction event. A hyperbolic diversification model is proposed, which accounts for the positive relationship between the intensity of interspecific competition and the rate of niche differentiation and resolves the conundrum of delayed rediversification at a time when niche space was largely vacated.
Data from: Evolutionary dynamics of quantitative variation in an adaptive trait at the regional scale: the case of zinc hyperaccumulation in Arabidopsis halleri
Metal hyperaccumulation in plants is an ecological trait whose biological significance remains debated, in particular because the selective pressures that govern its evolutionary dynamics are complex. One of the possible causes of quantitative variation in hyperaccumulation may be local adaptation to metalliferous soils. Here we explored the population genetic structure of Arabidopsis halleri at fourteen metalliferous and non-metalliferous sampling sites in Southern Poland. The results were integrated with a quantitative assessment of variation in zinc hyperaccumulation to trace local adaptation. We identified a clear hierarchical structure with two distinct genetic groups at the upper level of clustering. Interestingly, these groups corresponded to different geographic sub-regions, rather than to ecological types (i.e. metallicolous vs non-metallicolous). Also, approximate Bayesian computation analyses suggested that the current distribution of A. halleri in Southern Poland could be relictual as a result of habitat fragmentation caused by climatic shifts during the Holocene, rather than due to recent colonization of industrially polluted sites. In addition, we find evidence that some non-metallicolous lowland populations may have actually derived from metallicolous populations. Meanwhile, the distribution of quantitative variation in zinc hyperaccumulation did separate metallicolous and non-metallicolous accessions, indicating more recent adaptive evolution and diversifying selection between metalliferous and non-metalliferous habitats. This suggests that zinc hyperaccumulation evolves both ways – towards higher levels at non-metalliferous sites and lower levels at metalliferous sites. Our results open a new perspective on possible evolutionary relationships between A. halleri edaphic types that may inspire future genetic studies of quantitative variation in metal hyperaccumulation.
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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.