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Data from: Plasma mammalian leptin analogue predicts reproductive phenology, but not reproductive output in a capital-income breeding seaduck
To invest in energetically demanding life history stages, individuals require a substantial amount of resources. Physiological traits, particularly those related to energetics, can be useful for examining variation in life history decisions and trade-offs because they result from individual responses to environmental variation. Leptin is a protein hormone found in mammals that is proportional to the amount of endogenous fat stores within an individual. Recently, researchers have confirmed that a mammalian leptin analogue (MLA), based on the mammalian sequence of leptin, is present with associated receptors and proteins in avian species, with an inhibitory effect on foraging and body mass gain at high circulating levels. While MLA has been both quantified and manipulated in avian species, little is currently known regarding whether plasma MLA in wild-living species and individuals is associated with key reproductive decisions. We quantified plasma MLA in wild, Arctic-nesting female common eiders (Somateria mollissima) at arrival on the breeding grounds and followed them to determine subsequent breeding propensity, and reproductive phenology, investment, and success. Common eiders are capital-income breeding birds that require the accumulation of substantial fat stores to initiate laying and successfully complete incubation. We found that females with lower plasma MLA initiated breeding earlier and in a shorter period of time. However, we found no links between plasma MLA levels and breeding propensity, clutch size or reproductive success. Although little is still known about plasma MLA, based on the current study and due to its role in influencing foraging behaviours and condition gain, it appears to be closely linked to reproductive timing and is therefore likely to underlie trade-offs surrounding life history decisions.
Data from: Aerobic scope predicts dominance during early life in a tropical damselfish
A range of physiological traits are linked with aggression and dominance within social hierarchies, but the role of individual aerobic capacity in facilitating aggression has seldom been studied. Further, links previously observed between an individual's metabolic rate and aggression level may be context dependent and modulated by factors such as social stress and competitor familiarity. We examined these issues in juvenile Ambon damselfish, Pomacentrus amboinensis, which display intraspecific competition for territories during settlement on coral reefs. Individuals were measured for routine metabolic rate, aerobic scope, and anaerobic capacity using intermittent-flow respirometry before dyadic dominance contests. Post-contest, fish were measured for metabolic rate in isolation and while interacting with their previous competitor or a stranger in adjacent transparent respirometers. In arena contests, aerobic scope was correlated with aggression and dominance, while routine metabolic rate and anaerobic capacity were not related to dominance. Post-contest, subordinates showed a rise in metabolic rate and decrease in available aerobic scope, presumably due to social stress. Dominants increased metabolic rate in the presence of a previous competitor, possibly due to the stresses of hierarchy maintenance. Metabolic rate during aggressive interactions did not approach that measured during exhaustive exercise, suggesting individuals do not fully utilise their aerobic scope during aggression. A greater aerobic scope may, however, allow faster post-contest recovery. These results demonstrate a link between aerobic scope and dominance during intraspecific competition for territory. Selection on aerobic scope could therefore follow, either indirectly through correlations with other traits influencing resource-holding potential, or directly if aerobic scope carries benefits important for territory acquisition or holding, such as an enhanced capacity to cope with socially-induced stress.
Data from: Montane refugia predict population genetic structure in the Large-blotched Ensatina salamander
Understanding the biotic consequences of Pleistocene range shifts and fragmentation remains a fundamental goal in historical biogeography and evolutionary biology. Here, we combine species distribution models (SDM) from the present and two late Quaternary time periods with multilocus genetic data (mitochondrial DNA and microsatellites) to evaluate the effect of climate-induced habitat shifts on population genetic structure in the Large-blotched Ensatina (Ensatina eschscholtzii klauberi), a plethodontid salamander endemic to middle and high-elevation conifer forest in the Transverse and Peninsular Ranges of southern California and northern Baja California. A composite SDM representing the range through time predicts two disjunct refugia, one in southern California encompassing the core of the species range and the other in the Sierra San Pedro Mártir of northern Baja California at the southern limit of the species range. Based on our spatial model, we would expect a pattern of high connectivity among populations within the northern refugium and, conversely, a pattern of isolation due to long-term persistence of the Sierra San Pedro Mártir population. Our genetic results are consistent with these predictions based on the hypothetical refugia in that (i) historical measures of population connectivity among stable areas are correlated with gene flow estimates; and (ii) there is strong geographical structure between separate refugia. These results provide evidence for the role of recent climatic change in shaping patterns of population persistence and connectivity within the Transverse and Peninsular Ranges, an evolutionary hotspot.
Life history predicts flight muscle phenotype and function in birds
<p>1. Functional traits are the essential phenotypes that underlie an organism's life history and ecology. Although biologists have long recognized that intraspecific variation is consequential to an animals' ecology, studies of functional variation are often restricted to species-level comparisons, ignoring critical variation within species. In birds, interspecific comparisons have been foundational in connecting flight muscle phenotypes to species-level ecology, but intraspecific variation has remained largely unexplored.</p> <p>2. We asked how age- and sex-dependent demands on flight muscle function are reconciled in birds. The flight muscle is an essential multifunctional organ, mediating a large range of functions associated with powered flight and thermoregulation. These functions must be balanced over an individual's lifetime.</p> <p>3. We leveraged within- and between-species comparisons in a clade of small passerines (<em>Tarsiger</em> bush-robins) from the eastern edge of the Qinghai-Tibet Plateau. We integrated measurements of flight muscle physiology, morphology, behavior, phenology, and environmental data, analyzing trait data within a context of three widespread, adaptive life-history strategies – sexual dichromatism, age and sex-structured migration, and delayed plumage maturation. This approach provides a framework of the selective forces that shape functional variation within and between species.</p> <p>4. We found more variation in flight muscle traits within species than has been previously described between species of birds under 20 g. This variation was associated with the discovery of mixed muscle fiber types (i.e. both fast glycolytic and fast oxidative fibers), which differ markedly in their physiological and functional attributes. This result is surprising given that the flight muscles of small birds are generally thought to contain only fast oxidative fibers, suggesting a novel ecological context for glycolytic muscle fibers in small birds. Within each species, flight muscle phenotypes varied by age and sex, reflecting the functional demands at different life-history stages and the pressures that individuals face as a result of their multi-class identity (i.e. species, age, and sex).</p> <p>5. Our findings reveal new links between avian physiology, ecology, behavior, and life history, while demonstrating the importance of demographic-dependent selection in shaping functional phenotypic variation. </p>
Data from: Birth date predicts alternative life-history pathways in a fish with sequential reproductive tactics
In species with plastic expression of alternative reproductive tactics (ARTs), individuals of the same sex, usually males, can adopt different reproductive tactics depending on factors such as body size. The 'birth date hypothesis' proposes that condition-dependent expression of ARTs may ultimately depend on birth date, because individuals born at different times of the year may achieve different sizes and express different reproductive tactics accordingly. However, this has rarely been tested. Here, we tested this hypothesis in a fish with ARTs, the peacock blenny (Salaria pavo). A long-term (6 years) mark–recapture study demonstrated that ARTs in the peacock blenny were sequential and that males may follow at least two alternative life-history pathways: a nest-holder pathway, in which males express the nest-holder tactic from their first breeding season onwards, and a parasitic pathway, where males reproduce on their first breeding season as sneaker males and subsequently as nest-holders. We have found evidence of a birth date effect on the expression of ARTs in the peacock blenny. Males following the nest-holder pathway are born earlier and are larger at the first breeding season than males following the parasitic pathway, but they have similar growth curves. The mechanisms underlying a birth date effect are far from clear and might be diverse. We have not found support for a mechanism of body size threshold triggering sexual maturation and subsequent ARTs. A mechanism of tactic determination that is strictly based on timing of first maturation is also unlikely. A proxy of lifetime reproductive success shows crossing (body size associated) fitness curves for the two main life-history pathways.
Data from: Predicting the impacts of climate change on Papio baboon biogeography: are widespread, generalist primates 'safe'?
Aims: To explore whether wide-ranging, generalist primates like baboons can be presumed 'resilient' in the face of climate change. We identify environmental variables influencing baboons' current distributions and predict their future potential distributions under different climate change scenarios. Location: Africa and Arabia. Taxon: Baboons, Papio spp. Methods: We used localities for olive, yellow, Guinea, hamadryas, chacma and Kinda baboons together with high-resolution data on bioclimatic variables, altitude and vegetation to construct species distribution models (SDMs). These SDMs were run under current and future conditions, with future models based on three General Circulation Models (MIROC-ESM, CCSM4 and HadGEM2-ES) under two Representative Concentration Pathways (RCP2.5 and 6.0) for 2050 and 2070 to explore a range of different possible futures. Results: All SDMs produced AUC values >0.916 suggesting excellent overall performance. Altitude was the most important variable influencing Guinea baboon distributions (contributing 41.6%), temperature seasonality for olive and yellow baboons (47.5% and 35.4% respectively), precipitation of the driest month for hamadryas baboons (24.4%), annual mean precipitation for the Kinda baboon (45.1%) and mean temperature of the driest quarter for chacma baboons (41.4%). Chacma and Kinda baboons are predicted to suffer substantial habitat loss, and Guinea baboons may do the same if conditions aridify as climates warm. In contrast, all models for the olive and hamadryas baboons predicted an increase in suitable habitat and only smaller changes were predicted for the yellow baboon. Main conclusions: Two or three of six baboon taxa are at risk of significant habitat loss as climates warm despite their apparent ecological flexibility. The chacma and Kinda baboons (both IUCN listed as Least Concern) will be worst affected, followed by the Guinea baboon (Near Threatened) if warming brings aridification. We recommend more focus on biogeographic tools as a means of exploring vulnerabilities in seemingly resilient species.
Predicting barrier effects of transportation networks on Asian elephants: Implications for environmental impact assessment
<p>The rapid proliferation of transportation networks (TNs) is a threat to wide–ranged animals through habitat erosion, road–kill, and indirect socio–ecological interaction. In most cases, environmental impact assessments of TNs about animals are descriptive and targeted to direct impacts of the "linear features", while indirect and cumulative impacts are relatively neglected. Using spatially explicit data of elephant–caused damage during 2012–2015 in China, we quantified barrier effects of TN on Asian elephants and predicted the effects under a TN expansion scenario using maximum entropy algorithms. We found that TN acted as a strong barrier even for the elephants that have inhabited highly fragmented landscapes for years, with only 18% of the damage occurred on the crossed side of roads. Also, the TN expansion will reduce elephant habitats, exacerbating herd isolation and human–elephant conflict locally. Thus, we suggest that mitigation of the conflicts should be integrated into future environmental impact assessments.</p>
Data from: Altered embryonic development in northern bobwhite quail (Colinus virginianus) induced by pre-incubation oscillatory thermal stresses mimicking global warming predictions
Global warming is likely to alter reproductive success of ground-nesting birds that lay eggs normally left unattended for days or even weeks before actual parental incubation, especially in already warm climates. The native North American bobwhite quail (Colinus virginianus) is such a species, and pre-incubation quail eggs may experience temperatures >45°C. Yet, almost nothing is known about embryonic survival after such high pre-incubation temperatures. Freshly laid bobwhite quail eggs were exposed during a 12 day pre-incubation period to one of five thermal regimes: low oscillating temperatures (25-40°C, mean=28.9°C), high oscillating temperatures (30-45°C, mean=33.9°C), low constant temperatures (28.85°C), high constant temperatures (mean=33.9°C), or commercially employed pre-incubation temperatures (20°C). After treatment, eggs were then incubated at a standard 37.5°C to determine subsequent effects on embryonic development rate, survival, water loss, hatching, and embryonic oxygen consumption. Both quantity of heating degree hours during pre-incubation and specific thermal regime (oscillating vs. non-oscillating) profoundly affected important aspects of embryo survival and indices of development and growth Pre-incubation quail eggs showed a remarkable tolerance to constant high temperatures (up to 45°C), surviving for 4.5±0.3 days of subsequent incubation, but high oscillating pre-incubation temperature increased embryo survival (mean survival 12.2±1.8 days) and led to more rapid development than high constant temperature (maximum 38.5ºC), even though both groups experienced the same total heating degree-hours. Oxygen consumption was ~200-300 μl O2.egg.min-1 at hatching in all groups, and was not affected by pre-incubation conditions. Oscillating temperatures, which are the norm for pre-incubation quail eggs in their natural habitat, thus enhanced survival at higher temperatures. However, a 5°C increase in pre-incubation temperature, which equates to the predicted long-term increases of 5°C or more, nonetheless reduced hatching rate by approximately 50%. Thus, while pre-incubation bobwhite eggs may be resiliant to moderate oscillating temperature increases, global warming will likely severely impact wild bobwhite quail populations, especially in their strongholds in southern latitudes.
Data from: Predicted 2100 climate scenarios affects growth and skeletal development of tambaqui (Colossoma macropomum) larvae
Climate changes driven by greenhouse gas emissions have been occurring in an accelerated degree, affecting environmental dynamics and living beings. Among all affected biomes, the Amazon is particularly subjected to adverse impacts, such as temperature rises and water acidification. This study aimed to evaluate the impacts of predicted climate change on initial growth and development of an important Amazonian food fish, the tambaqui. We analyzed growth performance, and monitored the initial osteogenic process and the emergence of skeletal anomalies, when larvae were exposed to three climate change scenarios: mild (B1, increase of 1.8 °C, 200 ppm of CO2); moderate (A1B, 2.8 °C, 400 ppm of CO2); and drastic (A2, 3.4 °C, 850 ppm of CO2 ), in addition to a control room that simulated the current climatic conditions of a pristine tropical forest . The exposure to climate change scenarios (B1, A1B and A2) resulted in low survival, especially for the animals exposed to A2, (24.7 ± 1.0 %). Zootechnical performance under the B1 and A1B scenarios was higher when compared to current and A2, except for condition factor, which was higher in current (2.64 ± 0.09) and A1B (2.41 ± 0.14) scenarios. However, skeletal analysis revealed higher incidences of abnormalities in larvae exposed to A1B (34.82 %) and A2 (39.91 %) scenarios when compared to current (15.38 %). Furthermore, the bone-staining process revealed that after 16 days post-hatch (7.8 ± 0.01 mm total length), skeletal structures were still cartilaginous, showing no mineralization in all scenarios. We concluded that tambaqui larvae are well-adapted to high temperatures and may survive mild climate change . However, facing more severe climate conditions, its initial development may be compromised, resulting in high mortality rates and increased incidence of skeletal anomalies, giving evidence that global climate change will hamper tambaqui larvae growth and skeletal ontogeny.
Data from: Nest size is predicted by female identity and the local environment in the blue tit, but is not related to genetic or foster mother's nest size
The potential for animals to respond to changing climates has sparked interest in intraspecific variation in avian nest structure since this may influence nest microclimate and protect eggs and offspring from inclement weather. However, there have been relatively few large-scale attempts to examine variation in nests or the determinates of individual variation in nest structure within populations. Using a set of mostly pre-registered analyses, we studied potential predictors of variation in the size of a large sample (803) of blue tit (Cyanistes caeruleus) nests across three breeding seasons at Wytham Woods, UK. Whilst our pre-registered analyses found that individual females built very similar nests across years, there was no evidence in follow-up (post hoc) analyses that their nest size correlated to that of their genetic mother or, in a cross-fostering experiment, to the nest where they were reared. In further pre-registered analyses, spatial environmental variability explained nest size variability at relatively broad spatial scales, and especially strongly at the scale of individual nestboxes. Our study indicates that nest structure is a characteristic of individuals, but is not strongly heritable, indicating that it will not respond rapidly to selection. Explaining the within-individual and within-location repeatability we observed requires further study.
Data from: Prevalence of disruptive selection predicts extent of species differentiation in Lake Victoria cichlids
Theory suggests that speciation with gene flow is most likely when both sexual and ecological selection are divergent or disruptive. Divergent sexual and natural selection on the visual system have been demonstrated before in sympatric, morphologically similar, sister species of Lake Victoria cichlids, but this does not explain the subtle morphological differences between them. To investigate the significance of natural selection on morphology during speciation, we here ask whether the prevalence of disruptive ecological selection differs between sympatric sister species that are at different stages of speciation. Some of our species pairs do (Pundamilia) and others do not (Neochromis) differ distinctively in sexually selected male nuptial coloration. We find that 1) evidence for disruptive selection and for evolutionary response to it, is prevalent in traits that are differentiated between sister species; 2) prevalence of both predicts the extent of genetic differentiation; 3) genetic differentiation is weaker in species pairs with conserved male nuptial coloration. Our results speak to the existence of two different mechanisms of speciation with gene flow: speciation mainly by sexual selection tightly followed by ecological character displacement in some cases and speciation mainly by divergent ecological selection in others.
Data from: Predicting function from sequence in a large multifunctional toxin family
Venoms contain active substances with highly specific physiological effects and are increasingly being used as sources of novel diagnostic, research and treatment tools for human disease. Experimental characterisation of individual toxin activities is a severe rate-limiting step in the discovery process, and in-silico tools which allow function to be predicted from sequence information are essential. Toxins are typically members of large multifunctional families of structurally similar proteins that can have different biological activities, and minor sequence divergence can have significant consequences. Thus, existing predictive tools tend to have low accuracy. We investigated a classification model based on physico-chemical attributes that can easily be calculated from amino-acid sequences, using over 250 (mostly novel) viperid phospholipase A2 toxins. We also clustered proteins by sequence profiles, and carried out in-vitro tests for four major activities on a selection of isolated novel toxins, or crude venoms known to contain them. The majority of detected activities were consistent with predictions, in contrast to poor performance of a number of tested existing predictive methods. Our results provide a framework for comparison of active sites among different functional sub-groups of toxins that will allow a more targeted approach for identification of potential drug leads in the future.
Data from: Implications of a temperature increase for host plant range: predictions for a butterfly
Although changes in phenology and species associations are relatively well-documented responses to global warming, the potential interactions between these phenomena are less well understood. In this study, we investigate the interactions between temperature, phenology (in terms of seasonal timing of larval growth) and host plant use in the polyphagous butterfly Polygonia c-album. We found that the hierarchy of larval performance on three natural host plants was not modified by a temperature increase as such. However, larval performance on each host plant and temperature treatment was affected by rearing season. Even though larvae performed better at the higher temperature regardless of the time of the rearing, relative differences between host plants changed with the season. For larvae reared late in the season, performance was always better on the herbaceous plant than on the woody plants. In this species, it is likely that a prolonged warming will lead to a shift from univoltinism to bivoltinism. The demonstrated interaction between host plant suitability and season means that such a shift is likely to lead to a shift in selective regime, favoring specialization on the herbaceous host. Based on our result, we suggest that host range evolution in response to temperature increase would in this species be highly contingent on whether the population undergoes a predicted shift from one to two generations. We discuss the effect of global warming on species associations and the outcome of asynchrony in rates of phenological change.
Data from: Heterozygosity predicts clutch and egg size but not plasticity in a house sparrow population with no evidence of inbreeding
We investigated the link between heterozygosity and the reaction norm attributes of reproductive performance in female house sparrows (Passer domesticus). We collected data on clutch size, egg size, hatching success, and nestling survival in 2 816 nesting attempts made by 791 marked individuals over a 16 year period. Pedigree analysis revealed no evidence of inbreeding. Neither parent-offspring regression nor an animal model revealed significant heritability in clutch or egg size. We selected 42 females that laid at least seven clutches at our study site and used a survey of 21 autosomal microsatellite loci to estimate heterozygosity for each female. We controlled for phenotypic plasticity and found that both clutch and egg size showed significant positive correlations with heterozygosity. We found no evidence that heterozygosity influenced the slope of individual reaction norms. Further analysis suggested that clutch size was affected by heterozygosity across the genome, but egg size had more complex relationships, with evidence favoring the influence of multiple loci. Given the apparent lack of inbreeding and large population size, our results suggest associative overdominance as the likely mechanism for the impact of heterozygosity, but also created a puzzle about the process producing associations between neutral markers and the genes affecting clutch size or egg size. One possible explanation is a long term residual effect of the historical bottleneck that occurred when house sparrows were introduced into North America. The existence of HFCs in a population with considerable phenotypic plasticity and little inbreeding implies that the effects of heterozygosity may be more significant than previously thought.
Data from: Increased transgenerational epigenetic variation, but not predictable epigenetic variants, after environmental exposure in two apomictic dandelion lineages
DNA methylation is one of the mechanisms underlying epigenetic modifications. DNA methylations can be environmentally induced and such induced modifications can at times be transmitted to successive generations. However, it remains speculative how common such environmentally induced transgenerational DNA methylation changes are and if they persist for more than one offspring generation. We exposed multiple accessions of two different apomictic dandelion lineages of the Taraxacum officinale group (Taraxacum alatum and T. hemicyclum) to drought and salicylic acid (SA) treatment. Using methylation-sensitive amplified fragment length polymorphism markers (MS-AFLPs) we screened anonymous methylation changes at CCGG restriction sites throughout the genome after stress treatments and assessed the heritability of induced changes for two subsequent unexposed offspring generations. Irrespective of the initial stress treatment, a clear buildup of heritable DNA methylation variation was observed across three generations, indicating a considerable background rate of heritable epimutations. Less evidence was detected for environmental effects. Drought stress showed some evidence for accession-specific methylation changes, but only in the exposed generation and not in their offspring. By contrast, SA treatment caused an increased rate of methylation change in offspring of treated plants. These changes were seemingly undirected resulting in increased transgenerational epigenetic variation between offspring individuals, but not in predictable epigenetic variants. While the functional consequences of these MS-AFLP-detected DNA methylation changes remain to be demonstrated, our study shows that (1) stress-induced transgenerational DNA methylation modification in dandelions is genotype and context-specific; and (2) inherited environmental DNA methylation effects are mostly undirected and not targeted to specific loci.
Data from: Context-dependent survival, fecundity, and predicted population-level consequences of brucellosis in African buffalo
1. Chronic infections may have negative impacts on wildlife populations, yet their effects are difficult to detect in the absence of long-term population monitoring. Brucella abortus, the bacteria responsible for bovine brucellosis, causes chronic infections and abortions in wild and domestic ungulates, but its impact on population dynamics is not well understood. 2. We report infection patterns and fitness correlates of bovine brucellosis in African buffalo based on (1) 7 years of cross-sectional disease surveys and (2) a 4-year longitudinal study in Kruger National Park (KNP), South Africa. We then used a matrix population model to translate these observed patterns into predicted population-level effects. 3. Annual brucellosis seroprevalence ranged from 8·7% (95% CI = 1·8–15·6) to 47·6% (95% CI = 35·1–60·1) increased with age until adulthood (>6) and varied by location within KNP. Animals were on average in worse condition after testing positive for brucellosis (F = −5·074, P < 0·0001), and infection was associated with a 2·0 (95% CI = 1·1–3·7) fold increase in mortality (χ2 = 2·039, P = 0·036). Buffalo in low body condition were associated with lower reproductive success (F = 2·683, P = 0·034), but there was no association between brucellosis and pregnancy or being observed with a calf. 4. For the range of body condition scores observed in the population, the model-predicted growth rate was λ = 1·11 (95% CI = 1·02–1·21) in herds without brucellosis and λ = 1·00 (95% CI = 0·85–1·16) when brucellosis seroprevalence was 30%. 5. Our results suggest that brucellosis infection can potentially result in reduced population growth rates, but because these effects varied with demographic and environmental conditions, they may remain unseen without intensive, longitudinal monitoring.
Data from: A functional trade-off between trophic adaptation and parental care predicts sexual dimorphism in cichlid fish
Although sexual dimorphism is widespread in nature, its evolutionary causes often remain elusive. Here we report a case where a sex-specific conflicting functional demand related to parental care but not to sexual selection explains sexual dimorphism in a primarily trophic structure, the gill rakers of cichlid fishes. More specifically, we examined gill raker length in a representative set of cichlid fish species from Lake Tanganyika featuring three different parental care strategies: (i) uni-parental mouthbrooding, whereby only one parental sex incubates the eggs in the buccal cavity; (ii) bi-parental mouthbrooding, whereby both parents participate in mouthbrooding; and (iii) nest guarding without any mouthbrooding involved. As predicted from these different parental care strategies, we find sexual dimorphism in gill raker length to be present only in uni-parental mouthbrooders, but neither in bi-parental mouthbrooders nor in nest guarders. Moreover, variation in the extent of sexual dimorphism among uni-parental mouthbrooders appears to be related to trophic ecology. Overall, we present a so far unrecognised scenario for the evolution of sexual dimorphism that is not related to sexual selection or initial niche divergence between sexes. Instead, sexual dimorphism in gill raker length in uni-parental mouthbrooding cichlid fish appears to be the consequence of a sex-specific functional trade-off between a trophic function present in both sexes, and a reproductive function present only in the brooding sex.
Data from: Developing allometric models to predict the individual aboveground biomass of shrubs worldwide
Aim Existing global models to predict standing woody biomass are based on trees characterized by a single principal stem, well-developed in height. However, their use in open woodlands and shrublands, characterized by multistemmed species with substantial crown development, generates a high level of uncertainty in biomass estimates. This limitation led us to i) develop global predictive models of shrub individual aboveground biomass based on simple allometric variables; ii) to compare the fit of these models with existing global biomass models; and iii) to assess whether models fit change when bioclimatic variables are considered. Location Global. Time period Present. Major taxa studied 118 species. Methods We compile a database of 3243 individuals across 49 sites distributed worldwide. Including basal diameter, height and crown diameter as predictor variables, we built potential models and compared their fit using generalized least squares. We used mixed effects models to determine if bioclimatic variables improved the accuracy of biomass models. Results Although the most important variable in terms of predictive capacity was stem basal diameter, crown diameter significantly improved the models fit, followed by height. Four models were finally chosen, with the best model combining all these variables in the same equation (R2 = 0.930, RMSE = 0.476). Selected models performed as well as established global biomass models. Including the individual bioform significantly improved the models fit. Main conclusions Basal diameter, crown diameter and height measures could be combined to provide robust AGB estimates of individual shrub species. Our study supplements well-established models developed for trees, allowing more accurate biomass estimation of multistemmed woody individuals. We further provide tools for a methodological standardization of individual biomass quantification in these species. We expect these results contribute to improve the quality of biomass estimates across ecosystems, but also to generate methodological consensus on field biomass assessments in shrubs.
Data from: Using citizen-collected wildlife sightings to predict traffic strike hotspots for threatened species: a case study on the southern cassowary
Assessing the causal factors underpinning the distribution and abundance of wildlife road-induced mortality can be challenging. This is particularly ubiquitous for rare or elusive species, because traffic strikes occur infrequently for these populations and information about localized abundance, distribution, and movements are generally lacking. Here we assessed if citizen-collected sightings data may serve as a low cost and efficient means of gathering long-term animal road-side presence and road crossing information, which could then be used to assess the causative factors and direct mitigation actions aimed at reducing wildlife traffic strike frequency. We explored this principle using two decades of traffic strike records and citizen-collected sightings of the southern cassowary Casuarius casuarius johnsonii. Roads have bisected the cassowaries' rainforest habitat and despite considerable investment into mitigation strategies for this species, road-induced mortality is considered one of the primary threatening processes affecting the population. Using a Bayesian approach and controlling for spatial autocorrelation with conditional autoregressive (CAR) models, we demonstrate that traffic strikes are primarily a density-dependent process in the southern cassowary. That is, traffic strike clusters occurred along stretches of road where cassowaries were most frequently sighted. There were, however, road stretches where traffic strike frequency was greater than predicted by the number of road-side sightings, illustrating when and where density-independent processes increased the mortality potential for a road-crossing cassowary. Synthesis and applications. This is the first time that citizen-collected sightings data have been used to systematically inform upon the abundance and distribution of wildlife traffic strike. The technique not only predicts where incidents are likely to occur but also helps us to understand the factors responsible for strike clustering. While not a replacement for systematic surveys, we highlight citizen-collected sightings data as a low-cost option when assessing contributing factors to vehicle-induced mortality. Accounting for density-dependent and independent processes will ensure the most effective allocation of resources when implementing wildlife traffic strike mitigation.
Data from: Diagnostic accuracy of presepsin in predicting bacteremia in elderly patients admitted to the emergency department: prospective study in Japan
<p class="CxSpFirst"><span><b>Objective</b></span></p> <p class="CxSpMiddle"><span><a name="_Hlk1399924">Early detection of bacteremia in the elderly is needed in the emergency department (ED). </a></span></p> <p class="CxSpMiddle"><span><a name="_Hlk11878757"><b>Design, Setting, and Participants</b></a></span></p> <p class="CxSpMiddle"><span>Prospective study in Japan, single center trial in patients who satisfied the sepsis criteria was conducted between September 2014 and March 2016. Forty-six elderly patients aged ≥70 years were included.</span></p> <p class="CxSpMiddle"><span><b>Interventions</b></span></p> <p class="CxSpMiddle"><span>Blood sampling to evaluate C-reactive protein (CRP), procalcitonin (PCT) and presepsin plasma levels; two sets of blood sampling for bacterial cultures; and evaluations of the Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE II) scores were performed upon arrival at the ED. The results were compared between patients with bacteremia and those without bacteremia.</span></p> <p class="CxSpMiddle"><span><a name="_Hlk11878769"><b>Main Outcome Measure</b></a></span></p> <p class="CxSpMiddle"><span>The accuracy of detecting bacteremia</span></p> <p class="CxSpMiddle"><span><b>Results</b></span></p> <p class="CxSpMiddle"><span>The presepsin value was significantly higher in the bacteremia group than in the non-bacteremia group (866.6 ± 184.6 pg/mL vs. 639.9 ± 137.1 pg/mL, p = 0.03). The PCT and CRP did not significantly differ between the groups. The area under the receiver-operating-characteristic curve (AUC) values were not significantly different among presepsin (0.69), PCT (0.61), and CRP (0.53). Multivariate analysis showed that presepsin was independently associated with bacteremia (odds ratio, 8.84; 95% confidence interval, 0.95–81.79; p = 0.02).</span></p> <p class="CxSpMiddle"><span><b>Conclusion<a name="_Hlk1399945"></a></b></span></p> <p class="CxSpMiddle"><span>Presepsin could be a good biomarker to predict bacteremia in elderly patients with sepsis criteria admitted to the ED.</span></p>
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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.