cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5683/sp2/pejzrg
title: Data from: Phylogenetic history of vascular plant metabolism revealed using a macroevolutionary common garden

description: AbstractWhile the fundamental biophysics of C3 photosynthesis is highly conserved across plants, substantial variation in leaf structure and enzymatic activity translates into variability in rates of photosynthesis. Although this variation is well-documented, it remains poorly understood how photosynthetic rates evolve over short and long time scales, and whether these macroevolutionary changes are related to the evolution of key morphological and biochemical leaf traits. Large-scale comparative studies have been hampered by the substantial logistical and statistical challenges in disentangling evolutionary adaptation from environmental acclimation. Here we get around this limitation with a ‘macroevolutionary common garden’ approach in which we measured the metabolic traits Jmax and Vcmax from 111 phylogenetically diverse species in a shared environment. Using several phylogenetic comparative methods, we find substantial phylogenetic signal in these traits at shallow phylogenetic scales, but this signal dissipates quickly at deeper time scales. Leaf morphological traits exhibit phylogenetic signal over much deeper time scales, suggesting that these traits are less evolutionarily constrained than metabolic traits. Furthermore, we find that while morphological and biochemical traits (LMA, Narea and Carea) are weakly predictive of Jmax and Vcmax, evolutionary changes in these traits are mostly decoupled from changes in metabolic traits. This lack of tight evolutionary coupling implies that it may not be possible to use changes in these functional traits in response to global change to infer that photosynthetic strategy is also evolving.
DOI: 10.5683/sp2/uyugen
title: Participatory Mapping Reveals Sociocultural Drivers of Forest Fires in Protected Areas of the Post-Conflict Colombian Amazon

description: Abstract1. Wildfires have increased in protected areas (PAs) of the Colombian Amazon following the 2016 peace agreement between the Government and the Revolutionary Armed Forced of Colombia (FARC – Spanish acronym). Recent study efforts to understand this issue suffer from data scarcity and limited consultation of local stakeholder perspectives on factors affecting wildfires. 2. This study uses a social-ecological systems framework to investigate local perceptions of factors driving and / or preventing wildfires in the Los Picachos, La Macarena and Tinigua PAs, which are shared by two Amazonian departments experiencing wildfire increase. Four stakeholder categories were selected to represent varied and possibly conflicting interests: cattle ranchers, the national park service, local authorities and cross-sectional stakeholders. We combined a participative mapping approach with interviews to illustrate stakeholder perceptions of interactions between key variables in graphical causal models. Network analyses were used to determine areas of agreement on key variables, and to compare local priorities with those of key informants at the national level. 3. Local stakeholders and key informants widely agreed on the roles of extensive cattle ranching and land-grabbing as key drivers of wildfires. The analysis identified areas for further research into wildfire occurrence within PAs including lack of governance and untitled land, as well as the effects of poor access to basic public services on unsustainable ranching methods. 4. This study revealed contested opinions between ranchers and other stakeholders over interactions between ranching, roads and illicit crops, and consequently their effects on wildfire occurrence. This indicates the need for cautious implementation of the National Development Plan, prioritising road maintenance over expansion, integrating arable alternatives to cattle ranching, and considering multiple stakeholders in regional decision-making around wildfire reduction. The strengths and limitations of the participative mapping approach employed here are discussed with a view to aiding decision-making in post-conflict regions of the Global South. --
DOI: 10.5683/sp2/jhw3ro
title: Phosphorus deficiencies invoke optimal allocation of exoenzymes by ectomycorrhizas

description: AbstractEctomycorrhizal (EM) fungi can acquire phosphorus (P) through the production of extracellular hydrolytic enzymes (exoenzymes), but it is unclear as to the manner and extent native EM fungal communities respond to declining soil P availability. We examined the activity of six exoenzymes (xylosidase, N-acetyl glucosaminidase, b-glucosidase, acid phosphomonoesterase, acid phosphodiesterase [APD], laccase) from EM roots of Pseudotsuga menzesii across a soil podzolization gradient of coastal British Columbia. We found APD activity increased 4-fold in a curvilinear association with declining inorganic P. Exoenzyme activity was not related to organic P content, but at a finer resolution using 31P-NMR, there was a strong positive relationship between APD activity and the ratio of phosphodiesters to orthophosphate of organic horizons (forest floors). Substantial increases (2 to 5-fold) in most exoenzymes were aligned with declining foliar P concentrations of P. menzesii, but responses were statistically better in relation to foliar nitrogen (N):P ratios. EM fungal species with consistently high production of key exoenzymes were exclusive to Podzol plots. Phosphorus deficiencies in relation to N limitations may provide the best predictor of exoenzyme investment, reflecting an optimal allocation strategy for EM fungi. Resource constraints contribute to species turnover and the assembly of distinct, well-adapted EM fungal communities.
DOI: 10.5683/sp2/hqmpkc
title: 2D and 3D coral models imaged in Curaçao: George, Mullinix, et al PeerJ 2021

description: AbstractAbstract from the article associated with the dataset: George, Mullinix, et al PeerJ 2021. Reef-building corals are ecosystem engineers that compete with other benthic or- ganisms for space and resources. Corals harvest energy through their surface by photosynthesis and heterotrophic feeding, and they divert part of this energy to defend their outer colony perimeter against competitors. Here, we hypothesized that corals with a larger space-filling surface and smaller perimeters increase energy gain while reducing the exposure to competitors. This predicted an association between these two geometric properties of corals and the competitive outcome against other benthic organisms. To test the prediction, fifty coral colonies from the Caribbean island of Curac ̧ao were rendered using digital 3D and 2D reconstructions. The surface areas, perimeters, box-counting dimensions (as a proxy of space-filling property), and other geometric properties were extracted and analyzed with respect to the percentage of the perimeter losing or winning against competitors based on the coral tissue apparent growth or damage. The increase in surface space-filling dimension was the only significant single indicator of coral winning outcomes, but the combination of surface space-filling dimension with perimeter length increased the statistical prediction of coral competition outcomes. Corals with larger surface space-filling dimensions (Ds &gt; 2) and smaller perimeters displayed more winning outcomes, confirming the initial hypothesis. We propose that the space-filling property of coral surfaces complemented with other proxies of coral competitiveness, such as life history traits, will provide a more accurate quantitative characterization of coral competition outcomes on coral reefs. This framework also applies to other organisms or ecological systems that rely on complex surfaces to obtain energy for competition.
DOI: 10.5683/sp2/j016lt
title: Atmospheric pressure influencing ebullition and turbidity

description: AbstractMethane ebullition from lake sediment is an important source of atmospheric methane. Previous studies have suggested that temperature variations, water level changes, atmospheric pressure fluctuations and wind-induced current can affect ebullition. However, most of those studies were conducted during open-water season. There is a lack of observations during ice-cover, despite of the abundance of seasonally ice-covered lakes. In this dataset, we present high-frequency ebullition intensity data, atmospheric pressure data, bottom-water temperature data, and turbidite data from Base Mine Lake (57° 1' N, 111° 37' W in Alberta, Canada) during ice cover. During the study period, the water level in the lake is stable. Also, due to the ice cover, the impact of wind-induced current is negligible. The dataset shows that ebullition during ice cover is regulated by atmospheric pressure variations; the stable bottom-water temperature has on correlation with the ebullition. The dataset also shows that turbidity at depth in the lake increases during ebullition events.
DOI: 10.5683/sp2/8btwke
title: Food availability and long-term predation risk interactively affect antipredator response

description: AbstractFood availability and temporal variation in predation risk are both important determinants of the magnitude of antipredator responses, but their effects have rarely been examined simultaneously, particularly in wild prey. Here, we determine how food availability and long-term predation risk affect antipredator responses to acute predation risk by monitoring the foraging response of free-ranging snowshoe hares (Lepus americanus) to an encounter with a Canada lynx Lynx canadensis) in Yukon, Canada, over 4 winters (from 2015-2016 to 2018-2019). We examined how this response was influenced by natural variation in long-term predation risk (two-month mortality rate of hares) while providing some individuals with supplemental food. On average, snowshoe hares reduced foraging time up to 10 hours after coming into close proximity (≤ 75 m) with lynx, and reduced foraging time an average of 15.28 ± 7.08 minutes per lynx encounter. Hares tended to respond more strongly when the distance to lynx was shorter. More importantly, the magnitude of hares’ antipredator response to a lynx encounter was affected by the interaction between food-supplementation and long-term predation risk. Food-supplemented hares reduced foraging time more than control hares after a lynx encounter under low long-term risk, but decreased the magnitude of the response as long-term risk increased. In contrast, control hares increased the magnitude of their response as long-term risk increased. Our findings show that food availability and long-term predation risk interactively drive the magnitude of reactive antipredator response to acute predation risk. Determining the factors driving the magnitude of antipredator responses would contribute to a better understanding of the indirect effects of predators on prey populations.
DOI: 10.5683/sp2/etk2fk
title: Protecting the global ocean for biodiversity, food and climate

description: AbstractThe ocean contains unique biodiversity, provides valuable food resources, and is a major sink for anthropogenic carbon. Marine protected areas (MPAs) are an effective tool for restoring ocean biodiversity and ecosystem services but at present only 2.7% of the ocean is highly protected. This low level of ocean protection is due largely to conflicts with fisheries and other extractive uses. To address this issue, here we developed a conservation planning framework to prioritize highly protected MPAs in places that would result in multiple benefits today and in the future. We find that a substantial increase in ocean protection could have triple benefits, by protecting biodiversity, boosting the yield of fisheries, and securing marine carbon stocks that are at risk from human activities. Our results show that most coastal nations contain priority areas that can contribute substantially to achieving these three objectives of biodiversity protection, food provision, and carbon storage. A globally coordinated effort could be nearly twice as efficient as uncoordinated, national-level conservation planning. Our flexible prioritization framework could help to inform both national marine spatial plans and global targets for marine conservation, food security, and climate action.
DOI: 10.5683/sp2/fryyri
title: Enabling conditions for an equitable and sustainable blue economy

description: AbstractThe future of the global ocean economy is currently envisioned as an advancement towards a ‘Blue Economy’—socially equitable, environmentally sustainable, and economically viable ocean industries. However, there are current tensions between development discourses from perspectives of natural capital versus social equity and environmental justice. Here we show there are stark differences in Blue Economy outlooks when social conditions and governance capacity beyond resource availability are considered, and highlight limits to establishing multiple overlapping industries. The key differences in regional capacities to achieve a Blue Economy are not due to available natural resources, but include factors such as national stability, corruption, and infrastructure, that can be improved through targeted investments and cross-scale cooperation. Knowledge gaps can be addressed by integrating historical natural and social science information on the drivers and outcomes of resource use and management, thus identifying equitable pathways to establishing or transforming ocean sectors. Policy-makers must engage researchers and stakeholders to promote evidence-based, collaborative planning that ensures that sectors are chosen carefully, local benefits are prioritized, and the Blue Economy delivers on its social, environmental, and economic goals.
DOI: 10.5683/sp2/veszxt
title: Progressive neurochemical abnormalities in cognitive and motor subgroups of ALS: a prospective multicentre study

description: AbstractObjective: To evaluate progressive cerebral degeneration in amyotrophic lateral sclerosis (ALS) by assessing alterations in N-acetylaspartate (NAA) ratios in the motor and prefrontal cortex within clinical subgroups of ALS. Methods: Seventy-six ALS patients and 59 healthy controls were enrolled a prospective, longitudinal, multicenter study in the Canadian ALS Neuroimaging Consortium (CALSNIC). Participants underwent serial clinical evaluations and MRS at baseline, 4 and 8 months using a harmonized protocol across 5 centers. NAA ratios were quantified in the motor cortex and prefrontal cortex. Patients were stratified into subgroups based on disease progression rate, upper motor neuron (UMN) signs, and cognitive status. Linear mixed models were used for baseline and longitudinal comparisons of NAA metabolite ratios. Results: Patients with ALS had reduced NAA ratios in the motor cortex at baseline (P &lt; 0.001). Ratios were lower in those with more rapid disease progression and greater UMN signs (P &lt; 0.05). A longitudinal decline in NAA ratios was observed in the motor cortex in the rapid progressing (P &lt; 0.01) and high UMN burden (P &lt; 0.01) cohorts. The severity of UMN signs did not change significantly over time. NAA ratios were reduced in the prefrontal cortex only in cognitively impaired patients (P &lt; 0.05); prefrontal cortex metabolites did not change over time. Conclusions: Progressive degeneration of the motor cortex in ALS is associated with more aggressive clinical presentations These findings provide biological evidence of variable spatial and temporal cerebral degeneration linked to the disease heterogeneity of ALS. The use of standardized imaging protocols may have a role to play in clinical trials for patient selection or subgrouping. Classification of Evidence: This study provides Class II evidence that MRS NAA metabolite ratios of the motor cortex are associated with more rapid disease progression and greater UMN signs in patients with ALS.
DOI: 10.5683/sp2/sjuddo
title: Species interactions limit the predictability of community responses to environmental change

description: AbstractPredicting how ecological communities respond to environmental change is challenging, but highly relevant in this global change era. Ecologists commonly use current spatial relationships between species and environmental conditions to make predictions about the future. This assumes that species will track conditions by shifting their distributions. However, theory and experimental evidence suggest that species interactions prevent communities from predictably tracking temporal changes in environmental conditions, based on current spatial relationships between species and environmental gradients. We tested this hypothesis by assessing the dynamics of protist species in replicated two-patch microcosm landscapes that experienced different regimes of spatial and temporal environmental heterogeneity (light vs. dark). Populations were kept in monoculture or polyculture to assess the effect of species interactions. In monoculture, abundances were predictable based on current environmental conditions, regardless of whether they had experienced temporal environmental change. But, in polyculture, abundances depended also on the history of environmental conditions experienced. This suggests that, because of species interactions, communities should respond differently to spatial versus temporal environmental change. Thus, species interactions likely reduce the accuracy of predictions of future communities that are based on current spatial relationships between species and the environment.
DOI: 10.5683/sp2/npdhic
title: Data from: Examining the dynamics of Epstein-Barr virus shedding in the tonsils and the impact of HIV-1 coinfection on daily saliva viral loads

description: AbstractEpstein-Barr virus (EBV) is transmitted by saliva and is a major cause of cancer, particularly in people living with HIV/AIDS. Here, we describe the frequency and quantity of EBV detection in the saliva of Ugandan adults with and without HIV-1 infection and use these data to develop a novel mathematical model of EBV infection in the tonsils. Eligible cohort participants were not taking antiviral medications, and those with HIV-1 infection had a CD4 count &gt;200 cells/mm^3. Over a 4-week period, participants provided daily oral swabs that we analysed for the presence and quantity of EBV. Compared with HIV-1 uninfected participants, HIV-1 coinfected participants had an increased risk of EBV detection in their saliva (IRR=1.27, 95% CI=1.10-1.47) and higher viral loads in positive samples. We used these data to develop a stochastic, mechanistic mathematical model that describes the dynamics of EBV, infected cells, and immune response within the tonsillar epithelium to analyse potential factors that may cause EBV infection to be more severe in HIV-1 coinfected participants. The model, fit using Approximate Bayesian Computation, showed high fidelity to daily oral shedding data and matched key summary statistics. When evaluating how model parameters differed among participants with and without HIV-1 coinfection, results suggest HIV-1 coinfected individuals have higher rates of B cell reactivation, which can seed new infection in the tonsils and lower rates of an EBV-specific immune response. Subsequently, both these traits may explain higher and more frequent EBV detection in the saliva of HIV-1 coinfected individuals.
DOI: 10.5683/sp2/nmevqa
title: Ongoing production of low-fitness hybrids limits range overlap between divergent cryptic species

description: AbstractContact zones between recently-diverged taxa provide opportunities to examine the causes of reproductive isolation and the processes that determine whether two species can coexist over a broad region. The Pacific Wren (Troglodytes pacificus) and Winter Wren (Troglodytes hiemalis) are two morphologically similar songbirds that started diverging about 4 million years ago, older than most sister species pairs of temperate songbirds. The ranges of these species come into narrow contact in western Canada, where the two species remain distinct. To assess evidence for differentiation, hybridization, and introgression in this system, we examined variation in over 250,000 single nucleotide polymorphism markers distributed across the genome. The two species formed highly divergent genetic clusters, consistent with long-term differentiation. In a set of 75 individuals, two first-generation hybrids (i.e., F1’s) were detected, indicating only moderate levels of assortative mating between these taxa. We found no recent backcrosses or other evidence of recent breeding success of F1’s, indicating very low or zero fitness of F1 hybrids. Examination of genomic variation shows evidence for only a single backcrossing event many generations ago. The moderate rate of hybridization combined with very low F1 hybrid fitness is expected to result in a population sink in the contact zone, largely explaining the narrow overlap of the two species. If such dynamics are common in nature, they could explain the narrow range overlap often observed between pairs of closely related species.
DOI: 10.5683/sp2/zn6ycm
title: Signatures of mito-nuclear climate adaptation in a warbler species complex

description: AbstractMitochondrial (mtDNA) and nuclear (nDNA) genes interact to govern metabolic pathways of mitochondria. When differentiated populations interbreed at secondary contact, incompatibilities between mtDNA of one population and nDNA of the other could result in low fitness of hybrids. Hermit Warblers (S. occidentalis) and Townsend’s Warblers (Setophaga townsendi) exhibit distinct mtDNA haplotypes and a few nDNA regions of high differentiation, whereas coastal S. townsendi displays a mix of these genetic patterns consistent with ancient hybridization of S. occidentalis and inland S. townsendi. Of the few highly-differentiated nDNA regions between inland S. townsendi and S. occidentalis, two of these regions (on chromosome 5 and Z, respectively) are also differentiated between coastal and inland S. townsendi, similar to the mtDNA pattern. These two nDNA regions are associated with mitochondrial fatty acid metabolism. Moreover, these nDNA regions are correlated with mtDNA ancestries among sites, a pattern consistent with mito-nuclear co-adaptation. Such mito-nuclear coevolution might be driven by climate-related selection, because the mito-nuclear ancestry is correlated with climatic conditions among sampling sites. These results suggest that cryptic differentiation in this species complex has been shaped by climate-correlated adaptation associated with mito-nuclear fatty acid metabolism.
DOI: 10.5683/sp2/fr6h9s
title: Morphologic and metabolic data of Philaenus spumarius froghoppers

description: AbstractThe xylem sap of vascular plants is an unlikely source of nutrition, being both nutrient poor and held under tensions (negative pressures) that can exceed 1 MPa. But some insects feed on xylem sap exclusively, extracting copious quantities using a muscular cibarial pump. However, neither the strength of the insect’s suction, nor the direct energetic cost of xylem ingestion, have ever been quantified. Philaenus spumarius froghoppers were used to address these gaps in our knowledge. Micro-CT scans of its cibarium and measurements of cibarial muscle sarcomere length revealed that P. spumarius can generate a maximum tension of 1.3 ± 0.2 MPa within its cibarium. The energetic cost of xylem extraction was quantified using respirometry to measure the metabolic rate (MR) of P. spumarius while they fed on hydroponically-grown legumes, while xylem sap excretion rate and cibarial pumping frequency were simultaneously recorded. Increasing the plants’ xylem tensions up to 1.1 MPa by exposing their roots to polyethylene glycol did not reduce the insects’ rate of xylem excretion, but significantly increased both MR and pumping frequency. We conclude that P. spumarius can gain energy feeding on xylem sap containing previously reported energy densities and at xylem tensions up to their maximum suction capacity.