Find research datasets worth reusing

opencc-by-4.0Oct 2023View details →

Dataset: Maurel et al. "Hayabusa 2 returned samples reveal a weak to null magnetic field during aqueous alteration of Ryugu's parent body"

Samples: C0005 and A0154a from asteroid Ryugu (JAXA Hayabusa 2 mission), CI chondrite Orgueil, CM2 chondrite Daoura 003 <ul> <li>C0005: NRM, ARM, IRM demagnetization and anisotropy of ARM (AARM), IRM acquisition</li> <li>A0154a: NRM demagnetization, AARM</li> <li>Orgueil: NRM and ARM demagnetization</li> <li>Daoura 003: NRM demagnetization</li> </ul>

opencc-zeroDec 2023View details →

Competitors alter selection on alpine plants exposed to experimental climate change

Investigating how climate change alters selection regimes is a crucial step towards understanding the potential of populations to evolve in the face of changing conditions. Previous studies have mainly focused on understanding how changing climate directly influences selection, while the role of species' interactions has received little attention. Here, we used a transplant experiment along an elevation gradient to estimate how climate warming and competitive interactions lead to shifts in directional phenotypic selection on morphology and phenology of four alpine plants. We found that warming generally imposed novel selection, with the largest shifts in regimes acting on specific leaf area and flowering time across species. Competitors instead weakened the selection acting on traits that was imposed directly by warming. Weakened or absent selection in the presence of competitors was largely associated with the suppression of absolute means and variation of fitness. Our results suggest that although climate change can impose strong selection, competitive interactions within communities might act to limit selection and thereby stymie evolutionary responses in alpine plants facing climate change.

Reproductive state alters vocal characteristics of female North American red squirrels (Tamiasciurus hudsonicus)

Female advertisement of reproductive state and receptivity has the potential to play a large role in the mating systems of many taxa, but investigations of this phenomenon are underrepresented in the literature. North American red squirrels (Tamiasciurus hudsonicus) are highly territorial and engage in scramble competition mating, with males converging from spatially disparate territories to engage in mating chases. Given the narrow estrus window exhibited in this species, the ubiquitous use of vocalizations to advertise territory ownership, and the high synchronicity of males arriving from distant territories, we hypothesized that female vocalizations contain cues relating to their estrous state. To test this hypothesis, we examined the spectral and temporal properties of female territorial rattle vocalizations collected from females of known reproductive condition over 3 years. While we found no distinct changes associated with estrus specifically, we did identify significant changes in the spectral characteristics of rattles relating to both female body mass and reproductive state relative to parturition. To the best of our knowledge, this is the first evidence of changes in vocal characteristics associated with late pregnancy in a non-human mammal.

Data from: Parasite-mediated changes in host traits alter food web dynamics

Parasites commonly alter the phenotype of their host, thereby influencing competitive and consumer-resource interactions. This could trigger a cascade effect on the dynamics of biological communities, but the role of parasites in ecosystem processes is poorly understood. In this study, we investigate how parasite-induced trait modifications shape the dynamics of a complex lake food web using an allometric trophic network model (ATN). We simulated infections of stage-structured fish host populations via increased maintenance costs and predation risk. Our results show that host trait modifications can significantly impact host demography, with stage-specific biomass declines up to 60%. However, less severely affected host stages buffered these effects and sustained the population. Importantly, host biomass decline altered the dynamics of species interactions and these effects cascaded through the entire community, with biomass changes observed at all trophic levels. Our findings emphasize the importance of incorporating both indirect parasite effects and host life history in ecological network studies for more realistic simulations of community dynamics.

Data for: Microbe-induced plant resistance alters aphid inter-genotypic competition leading to rapid evolution with consequences for plant growth and aphid abundance

Plants and insect herbivores are two of the most diverse multicellular groups in the world, and both are strongly influenced by interactions with the belowground soil microbiome. Effects of reciprocal rapid evolution on ecological interactions between herbivores and plants have been repeatedly demonstrated, but it is unknown if (and how) the soil microbiome could mediate these eco-evolutionary processes on a shared host plant. We tested the role of a plant-beneficial soil bacterium (Acidovorax radicis) in altering eco-evolutionary interactions between different aphid genotypes (Sitobion avenae; genotypes Sickte and Fescue) feeding on barley (Hordeum vulgare). We measured fecundity, longevity and population growth of two aphid genotypes reared separately or together (population mixture) on three different barley varieties that were inoculated with or without A. radicis. Results showed that across all plant varieties A. radicis increased plant growth and suppressed aphid populations via reduced longevity and fecundity. The strength of effect was dependent on aphid genotype and barley variety, while the direction of effect was altered by aphid population mixture. Using Lotka-Volterra modelling, we demonstrated that while A. radicis inoculation decreased growth rates for both aphid genotypes it increased the competitiveness of one genotype against the other. In general, in the presence of A. radicis, the Fescue aphid genotype became more inhibitory of Sickte aphids, while Sickte aphids facilitated the growth of Fescue aphids. Our work demonstrates that plant rhizosphere microbiomes exert community-level influences by mediating eco-evolutionary interactions between herbivores and host plants. By altering competitive interaction outcomes among aphids and thus impacting processes such as rapid evolution, soil microbes contribute to the short- and long-term structure and functioning of terrestrial habitats.

Ant handling changes myrmecochore seed coat microbiomes and alters diversity of seed-borne plant pathogenic fungi

The putative benefits to seeds in myrmecochory (ant-mediated seed dispersal) are often cast in a reward context. However, microbes have been mostly overlooked as seed mortality agents in myrmecochory, as have potential treatments provided by ant-handling. We investigated the effects of ant handling on the diversity of seed coat fungal communities of three myrmecochorous plant species. Ant-handling altered measures of both alpha and beta diversity of fungal communities. Ant-handled seeds harbored different overall fungal communities and plant pathogen communities than non-ant-handled seeds. The myrmecochore pathogenic fungal community showed high dissimilarity (high pairwise community turnover) between ant-handled and control seeds, while beta diversity measures for ant-handled seeds and seeds with manually-removed elaiosomes were less dissimilar. Ant handling may offer an additional benefit to myrmecochorous seeds via the reduction of the seed coat pathogenic community, which may be driven by elaiosome removal or as a byproduct of ant cleaning behaviors and chemical secretions.

R scripts, input and output data for: Season of death, pathogen persistence and wildlife behaviour alter number of anthrax secondary infections from environmental reservoirs

An important part of infectious disease management is predicting factors that influence disease outbreaks, such as R, the number of secondary infections arising from an infected individual. Estimating R is particularly challenging for environmentally transmitted pathogens given time lags between cases and subsequent infections. Here, we calculated R for Bacillus anthracis infections arising from anthrax carcass sites in Etosha National Park, Namibia. Combining host behavioural data, pathogen concentrations, and simulation models, we show that R is spatially and temporally variable, driven by spore concentrations at death, host visitation rates and early preference for foraging at infectious sites. While spores were detected up to a decade after death, most secondary infections occurred within two years. Transmission simulations under scenarios combining site infectiousness and host exposure risk under different environmental conditions led to dramatically different outbreak dynamics, from pathogen extinction (R<1) to explosive outbreaks (R>10). These transmission heterogeneities may explain variation in anthrax outbreak dynamics observed globally, and more generally, the critical importance of environmental variation underlying host-pathogens interactions. Notably, our approach allowed us to estimate the lethal dose of a highly virulent pathogen non-invasively from observational studies and epidemiological data, useful when experiments on wildlife are undesirable or impractical.

opencc-zeroMar 2024View details →

Cerebral microstructural alterations in Post-COVID-condition are related to cognitive impairment, olfactory dysfunction, and fatigue

After contracting COVID-19, a substantial number of individuals develop a Post-COVID-Condition (PCC), marked by neurologic symptoms such as cognitive deficits, olfactory dysfunction, and fatigue, which can have detrimental socioeconomic consequences. Despite this, biomarkers and pathophysiological understandings of this condition remain limited. Employing magnetic resonance imaging, we conduct a comparative analysis of cerebral microstructure among patients with post-COVID condition, healthy controls, and individuals who contracted COVID-19 without long-term symptoms. This reveals widespread alterations in cerebral microstructure, attributed to a shift in volume from neuronal compartments to free fluid, associated with the severity of the initial infection. Correlating these alterations with cognition, olfaction, and fatigue unveils distinct affected networks, which are in a close anatomical-functional relationship with the respective symptoms. This plausibility of symptom-specific networks not only provides insights into the disease's pathophysiological foundations, which align well with an accelerated aging process but also underscores the significance of microstructure as an imaging biomarker.

opencc-zeroApr 2024View details →

Climate change may alter the signal of plant facilitation in Mediterranean drylands

Facilitation is an ecological interaction that has allowed plant lineages to survive past climate aridification. This same interaction can be expected to buffer the effects of current climate change, which is tending to become more arid in the Mediterranean basin. However, facilitation may wane when stress conditions are extreme. Here we argue that the erosion of the facilitation signal between Quercus ilex and its nurses detected by García-Fayos et al. (2020) along 50 years in the eastern Iberian Peninsula may have been due to the reversion of facilitation to competition imposed by an increasingly arid climate. To support this speculation, we reconstructed the climatic niche of Q. ilex and its nurses as well as the local climate change occurring in the populations studied. We found that the decreasing trend in precipitation is pushing Q. ilex out of its climatic optimum in the stressful (semi-arid) but not in the mild (sub-humid) habitats. These results suggest that facilitation will be unable to mitigate the effects of climate change, especially those related to aridification. However, other scenarios linking climatic change with herbivory and rural abandonment should be considered to fully understand the past, present and future of facilitation interactions. Reconstructing past interactions can serve as an early warning signal about the future of populations in the face of climate change.

opencc-by-4.0Apr 2024View details →

Supplementary data of article "Domestication has altered gene expression and secondary metabolites in pea seed coat".

Table S1. Excel- GO_terms_MF_selected_WGCNA_modules. Table S2. Excel- GO_terms_MF_DEGs_UP_and_DOWN. Table S3. Excel- GO_terms_MF_DEGs_summary. Table S4. Excel- List of DEGs involved in flavonoid pathway found in WILD gene set. Table S5. Protein recoveries calculated for individual pea protein samples. Numbers 1, 2, 3 denote treatment groups corresponding to seed developmental stages (D1, D2 and mature seeds, respectively). Letters a–d denote biological replicates within the treatment groups. Table S6. Excel- Annotation of proteins differentially expressed in wild and domesticated pea seed coat samples. Table S7. Primary metabolites identified by spectral similarity library search and/or co-elution with authentic standards in pea seed coats aqua methanolic extracts. Metabolite analysis relied on GC-EI-Q-MS analysis after derivatization of the lyophilized extracts with methoxamine hydrochloride (MOA) and N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA). Table S8. Primary metabolites detected in the aq. methanolic extracts of mature Cameor seed coats demonstrating statistically significant up- and down-regulation in comparison to those of wild JI261. Table S9. Primary metabolites of mature JI92 seed coats demonstrating statistically significant up- and down-regulation in comparison with those of wild JI261. Table S10. Primary metabolites of mature JI1794 seed coats demonstrating statistically significant up- and down-regulation in comparison with those of JI261. Table S11. Primary metabolites of mature JI64 seed coats demonstrating statistically significant up- and down-regulation in comparison with those of JI261. Table S12. Mass analyzer settings applied for QqTOF-MS experiments in analysis of seed coat (cell wall) hydrolyzates and reference authentic standards. Table S13. Cell wall-bound metabolites extracted from the seed coats of wild (JI64, JI1794, JI261) and domesticated (Cameor, JI92) peas upon alkali hydrolysis of corresponding isolated and purified cell wall material. Table S14. Excel- Coordinates of markers in S-plot obtained from OPLS-DA analysis (FIA-ESI-HRTMS, negative ionization, lock mass uncorrected). Table S15. List of identified significantly differential metabolites rising during seed coat development. Table S16. List of identified significantly differential metabolites decreasing during seed coat development (positive ionization mode). Table S17. List of identified metabolites with significantly higher content in wild compared cultivated genotypes in older developmental stages (D5-6). Table S18. Excel- Expression of genes encoding enzymes of monolignol pathway in seed coats (SC) and embryos (E) of domesticated (Cameor, JI92 and Pisum abyssinicum PI358617) and wild (JI64, JI1794, JI261) peas over five seed developmental stages (13, 17, 20, 23, 28 DAP, labelled as 1-5). PAL: phenylalanine ammonia-lyase, C4H: cinnamate-4-hydroxylase, 4CL: 4-coumaroyl: CoA ligase, HCT: hydroxycinnamoyl CoA:shikimate hydroxycinnamoyltransferase, COMT: caffeic acid O-methyltransferase, CSE: caffeoyl shikimate esterase, CAD: cinnamyl alcohol dehydrogenase, CCR: cinnamoyl CoA reductase, CCoAMT: caffeoyl CoA-3-methyltransferase, F5H: ferulate-5-hydroxylase Table S19. Studied metabolites of phenylpropanoid pathway. Table S20. Instrument settings used in the proteomics LIT-Orbitrap-MS and -MS/MS experiments. Table S21. Procedures and specific settings for data processing and post-processing of the proteomics data. Table S22. Gas chromatographic (GC) separation conditions and electron ionization-quadrupole-mass spectrometry (EI-Q-MS) settings for GC-EI-Q-MS analysis of the primary metabolites in pea seed coats. Table S23. Chromatographic conditions used for UHPLC separation of seed coat (cell wall) hydrolyzates and reference authentic standards. Table S24. Variable parameters of MS/cIMS/MS measurements. Figure S1. The dynamics of gene expression between studied developmental stages within all genotypes (a) or among genotypes in particular developmental stages (b). Figure S2. Twelve representative groups of transcription factors described within 20 gene modules of pea SC. Visualized by Cytoscape 3.9.0. Figure S3. SDS-PAGE electropherograms of the total protein fractions isolated from the seed coats of JI92 (a, c, e) and JI64 (b, d, f) seeds before and after tryptic hydrolysis. Numbers 1, 2, 3 denote seed developmental stages: DS1, DS2 and mature seeds, respectively. Letters a-d denote biological replicates. The aliquots (10 μg) of samples before hydrolysis (a, b), the incompletely digested aliquots left on filter unit after peptide elution (c, d) and aliquots of tryptic hydrolysates (corresponding to 5 μg of protein), (e, f) were loaded on gels. Inter-gel normalization relied on the total density of the Protein Ladder (PageRuler™ Prestained Protein Ladder #26616, 10–180 kDa) lane (St); the ND (non-digested) sample represents a reference protein not subjected to hydrolysis. Figure S4. The numbers of tryptic peptides (a), possible proteins (b), and non-redundant proteins (protein groups) (c) identified in domesticated JI92 seed coats at developmental stages D1, D2 and D6. The tryptic digests (n =&thinsp;3) obtained from seed coats were analyzed by nano-high performance liquid chromatography-electrospray ionization linear ion trap-orbital trap mass spectrometry (nanoHPLC-ESI-LIT-Orbitrap-MS) operated in positive DDA mode. Figure S5. The numbers of tryptic peptides (a), possible proteins (b), and non-redundant proteins (protein groups, c) identified in wild pea JI64 seed coats at D1, D2 and D6 stages. The tryptic digests (n =&thinsp;3), obtained from pea seedlings, were analyzed by nano-high performance liquid chromatography-electrospray ionization linear ion trap-orbital trap mass spectrometry (nanoHPLC-ESI-LIT-Orbitrap-MS) operated in positive DDA mode. Figure S6. Principal component analysis (PCA) with score plot representation (a) accomplished for seed coat proteins differentially expressed at developmental stages D1 and D2 and in the mature state (D6) and hierarchical clustering with a heatmap representation (b). Figure S7. Functional annotation (accomplished with the Mercator MapMan v3.6 tool) of the pea seed coat proteins isolated in stage D1. White and black columns denote the functional groups of the proteins, which were more expressed in the developing seeds of domesticated JI92 and wild JI64, respectively. Figure S8. Functional annotation (accomplished with the Mercator MapMan v3.6 tool) of the pea seed coat proteins isolated in stage D2. White and black columns denote the functional groups of the proteins, which were more expressed in the developing seeds of the domesticated JI92 and wild JI64, respectively. Figure S9. Prediction of sub-cellular localization of the proteins more expressed in the developing seeds of JI92 and JI64 with the BUSCA prediction tool. Figure S10. Evaluation of the differences in the metabolic profiles of the mature seeds obtained from the wild JI261 and domesticated Cameor by principal component analysis (PCA). Figure S11. Representation of the differences in the metabolic profiles of the mature seed coats obtained from the wild JI261 and domesticated Cameor by the t-test with Volcano plot representation (a) and the top 30 differentially abundant metabolites demonstrating the most pronounced differences of corresponding GC-MS signals associated with seed dormancy (b). Figure S12. Evaluation of the differences in the metabolic profiles of the mature seeds obtained from the wild JI261 and domesticated JI92 by principal component analysis (PCA) with score plot representation (a) and hierarchical clustering with heatmap representation (b). Figure S13. Principal component analysis (PCA) illustrating distribution of metabolic profiles of mature seed coats of two wild pea genotypes, JI1794 and JI261. Figure S14. Principal component analysis (PCA) demonstrates the distribution of mature seed coat metabolic profiles of two wild pea genotypes, JI64 and JI261(control). Figure S15. Evaluation of the differences in the patterns of the cell wall-bound metabolites obtained from mature seed coats of wild JI261 and domesticated Cameor: principal component analysis (PCA) with score plot representation (a), hierarchical clustering with heatmap representation (b) and t-test analysis with the Volcano-plot representation (c). Figure S16. Statistical analysis (t-test with Volcano plot representation) characterizing the differences between the levels of mature seed coat cell wall-bound metabolites of Cameor compared with those of wild JI261. Figure S17. Principal component analysis (PCA) illustrates the distribution of mature seed coat metabolic profiles of domesticated JI92 and wild JI261. Figure S18. Principal component analysis (PCA) shows the distribution of metabolic profiles of mature seed coats of two wild pea genotypes, JI1794 and JI261, control. Figure S19. Principal component analysis (PCA) demonstrates the distribution of mature seed coat metabolic profiles of two wild genotypes, JI64 and control JI261. Figure S20. Annotated cell wall-bound metabolites extracted from the seed coats of the dormant wild pea genotype JI261 and the seed coats from several pea genotypes varying in their dormancy (Cameor, JI92, JI64, and JI1794) upon alkali hydrolysis of corresponding isolated and purified cell wall material.  Figure S21. Ion mobility separation of m/z 299.0841. Figure S22. Ion mobility separation of m/z 701.1907.  Figure S23. Ion mobility separation of m/z 619.1041. Figure S24. Ion mobility separation of m/z 631.1017. Figure S25. Ion mobility separation of m/z 641.1139. Figure S26. Ion mobility separation of m/z 771.1346.  Figure S27. Reconstructed chromatograms of p-hydroxybenzoic and salicylic acids in DS5 of dormant JI64 and domesticated landraces JI92 (LC/HRTMS, negative ionization mode). Figure S28. Module-trait relationship depiction showing the correlation between expression of the gene modules and the abundance of identified metabolites of the monolignol pathway.

opencc-zeroApr 2024View details →

Data from: Ecology of fear alters behaviour of grizzly bears exposed to bear-viewing ecotourism

Humans are perceived as predators by many species and may generate landscapes of fear, influencing the spatiotemporal activity of wildlife. Additionally, wildlife might seek out human activity when faced with predation risks (human shield hypothesis). We used the Anthropause, a decrease in human activity resulting from the COVID-19 pandemic, to test the ecology of fear and human shield hypotheses and quantify the effects of bear-viewing ecotourism on grizzly bear (Ursus arctos) activity. We deployed camera traps in the Khutze watershed in Kitasoo Xai'xais Territory in the absence of humans in 2020 and with experimental treatments of variable human activity when ecotourism resumed in 2021. Daily bear detection rates decreased with more people present and increased with days since people were present. Human activity was also associated with more bear detections at forested sheltered sites, and less at exposed sites, likely due to the influence of habitat on bear perception of safety. The number of people negatively influenced adult male detection rates, but we found no influence on females with young detections, providing no evidence that females responded behaviourally to a human shield effect from reduced male activity. We also observed apparent trade-offs of risk avoidance and foraging. When salmon levels were moderate to high, detected bears were more likely to be females with young than adult males on days with more people present. Should managers want to minimize human impacts on bear activity and maintain baseline age-sex class composition at ecotourism sites, multi-day closures and daily occupancy limits may be effective. More broadly, this work revealed that antipredator responses can vary with the intensity of risk cues, habitat structure, and forage trade-offs, as well as manifest as the altered age-sex class composition of individuals using human-influenced areas, highlighting that wildlife avoids people across multiple spatiotemporal scales.

opencc-zeroFeb 2024View details →

Vibroscape analysis reveals acoustic niche overlap and plastic alteration of vibratory courtship signals in ground-dwelling wolf spiders

Soundscape ecology has enabled researchers to investigate natural interactions among biotic and abiotic sounds as well as their influence on local animals. To expand the scope of soundscape ecology to encompass substrate-borne vibrations (i.e. vibroscapes), we developed methods for recording and analyzing sounds produced by ground-dwelling arthropods to characterize the vibroscape of a deciduous forest floor using inexpensive contact microphone arrays followed by automated sound filtering and detection in large audio datasets. Through the collected data, we tested the hypothesis that closely related species of Schizocosa wolf spider partition their acoustic niche. In contrast to previous studies on acoustic niche partitioning, two closely related species - S. stridulans and S. uetzi - showed high acoustic niche overlap across space, time, and/or signal structure. Finally, we examined whether substrate-borne noise, including anthropogenic noise (e.g., airplanes) and heterospecific signals, promotes behavioral plasticity in signaling behavior to reduce the risk of signal interference. We found that all three focal Schizocosa species increased the dominant frequency of their vibratory courtship signals in noisier signaling environments. Also, S. stridulans males displayed increased vibratory signal complexity with an increased abundance of S. uetzi, their sister species with which they are highly overlapped in the acoustic niche.

opencc-by-4.0Nov 2024View details →

Evaluating the Role of Biochar in Altering Chlorinated Phenol Behavior in Alluvial Soil Systems

<div> <div> <div> <div> <div> </div> </div> </div> </div> </div> <div> <div> <div> <div> <div> <div> Row and modelled data were obtained for four types of chlorinated phenols during transport in sandy alluvial soil and biochar-enriched soil. Raw data are provided for the characterization of sandy alluvial soil used in this study. The data are used for the preparation of a manuscript titled Evaluating the Role of Biochar in Altering Chlorinated Phenol Behavior in Alluvial Soil Systems. </div> </div> </div> </div> </div> </div>

opencc-by-4.0Nov 2024View details →

Data for "Archetypal flow regime change classes and their associations with anthropogenic drivers of global streamflow alterations"

Data repository for "Archetypal flow regime change classes and their associations with anthropogenic drivers of global streamflow alterations"

opencc-by-nc-4.0Apr 2020View details →

CLDF dataset derived from Grollemund et al.'s "Bantu expansion shows habitat alters the route and pace of human dispersals" from 2015

Cite the source of the dataset as: <blockquote> Grollemund, Rebecca, Branford, Simon, Bostoen, Koen, Meade, Andrew, Venditti, Chris, & Pagel, Mark (2015) Bantu expansion shows habitat alters the route and pace of human dispersals. Proc Natl Acad Sci USA. doi:10.1073/pnas.1503793112. </blockquote>

opencc-zeroDec 2021View details →

Calibrating phylogenies assuming bifurcation or budding alters inferred macroevolutionary dynamics in a densely sampled phylogeny of bivalve families

Analyses of evolutionary dynamics can be profoundly affected by age calibrations of phylogenetic nodes under different models of lineage branching. Most time-calibrated molecular phylogenies of extant taxa assume a purely bifurcating model, where nodes are calibrated using the daughter lineage with the older first occurrence in the fossil record. Lineages can also split via budding, in which a parent lineage persists following the origin of a daughter lineage, and nodes are calibrated using the age of the lineage with the younger first occurrence. Here, we use the extensive fossil record of bivalve molluscs for a large-scale empirical test of how the choice of branching model affects macroevolutionary analyses. We time-calibrated 91% of nodes in a phylogeny of 97 extant bivalve families using 86 calibration points ranging in age from 2.59 to 485 Ma. Allowing budding-based calibrations minimizes conflict between the tree topology and timing of evolutionary events in the fossil record, reducing the summed duration of inferred "ghost lineages," from 6.76 billion yrs (Gyr; bifurcating model) to 1.00 Gyr (budding model). Adding 31 extinct paraphyletic families – many major groups contain such extinct taxa – shifts deep splits further back in time and raises ghost-lineage totals to 7.86 Gyr (bifurcating) and 1.92 Gyr (budding), but more accurately reflects the time since separation of lineages. Lineage-through-time plots from phylogenetic data scaled under a bifurcating model of evolution push more inferred bivalve diversification into the Paleozoic, conflicting with other palaeontological evidence on the magnitude of the end-Paleozoic extinction and subsequent recovery, and strongly reduce the magnitude of the Cenozoic diversification of the group. Consideration of the hypothesized branching model within a given clade is essential when node-calibrating phylogenies, and for a major clade with a robust fossil record, an evolutionary model that allows budding and does not force bifurcations is the most appropriate one, and likely common for many other clades as well.

opencc-zeroDec 2021View details →

Group composition of individual personalities alters social network structure in experimental populations of forked fungus beetles

Social network structure is a critical group character that mediates the flow of information, pathogens, and resources among individuals in a population, yet little is known about what shapes social structures. In this study, we experimentally tested whether social network structure depends on the personalities of group members. Replicate groups of forked fungus beetles (Bolitotherus cornutus) were engineered to include only members previously assessed as either more social or less social. We found that individuals behaved consistently across social contexts, exhibiting repeatable numbers of interactions and numbers of partners. At the group level, networks composed of more social individuals had higher interaction rates, higher tie density, higher global clustering, and shorter average shortest paths than those composed of less social individuals. We highlight group composition of personalities as a source of variance in group traits and a potential mechanism by which networks could evolve.

opencc-by-4.0Jan 2022View details →

Data archive for 'Opportunities to curb hydrological alterations via dam re-operation in the Mekong'

This repository contains the data used in the paper '<a href="https://www.nature.com/articles/s41893-022-00971-z">Opportunities to curb hydrological alterations via dam re-operation in the Mekong</a>'. We first use VIC-Res to simulate daily river discharge and available hydropower generation of the Mekong basin from 1996 to 2016 under 32 scenarios (NAT (natural flow conditions), BAU (business as usual), MAX_MB (dams kept at full storage in Mekong), MAX_LMB (dams kept at full storage in Lower Mekong), and 28 OPT (optimized re-operation strategies) scenarios). The 'VIC-Res' folder contains the daily discharge at Stung Treng and hydropower production in Cambodia, Laos, and Thailand. The hydropower outputs are then used in PowNet, a unit commitment/economic dispatch model for the Cambodian, Laotian, and Thai power systems. 'PowNet' folder contains the relevant input and output files for the three scenarios that are elaborated on in the paper (BAU, MAX_LMB, and OPT). For more information on the PowNet models, refer to the following GitHub repositories: <a href="https://github.com/kamal0013/PowNet">PowNet-Cambodia</a>, <a href="https://github.com/kamal0013/PowNet-Laos">PowNet-Laos</a>, <a href="https://github.com/kamal0013/PowNet-Thailand">PowNet-Thailand</a>.

opencc-zeroFeb 2022View details →

Temperature and nutrient availability alter consequences of phenological shifts in predatory-prey communities

While there is mounting evidence indicating that the relative timing of predator and prey phenologies shapes the outcome of trophic interactions, we still lack a comprehensive understanding of how important the environmental context (e.g. abiotic conditions) is for shaping this relationship. Environmental conditions not only frequently drive shifts in phenologies, but they can also affect the very same processes that mediate the effects of phenological shifts on species interactions. Thus, identifying how environmental conditions shape the effects of phenological shifts is key to predict community dynamics across a heterogenous landscape and how they will change with ongoing climate change in the future. Here I tested how environmental conditions shape effects of phenological shifts by experimentally manipulating temperature, nutrient availability, and relative phenologies in two predator-prey freshwater systems (mole salamander- bronze frog vs dragonfly larvae-leopard frog). This allowed me to (1) isolate the effect of phenological shifts and different environmental conditions, (2) determine how they interact, and (3) how consistent these patterns are across different species and environments. I found that delaying prey arrival dramatically increased predation rates, but these effects were contingent on environmental conditions and predator system. While both nutrient addition and warming significantly enhanced the effect of arrival time, their effect was qualitatively different: Nutrient addition enhanced the positive effect of early arrival while warming enhanced the negative effect of arriving late. Predator responses varied qualitatively across predator-prey systems. Only in the system with strong gape-limitation were predators (salamanders) significantly affected by prey arrival time and this effect varied with environmental context. Correlations between predator and prey demographic rates suggest that this was driven by shifts in initial predator-prey size ratios and a positive feedback between size-specific predation rates and predator growth rates. These results highlight the importance of accounting for temporal and spatial correlation of local environmental conditions and gape-limitation in predator-prey systems when predicting the effects of phenological shifts and climate change on predator-prey systems.