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In Situ Evidence for Quantitative Nitrogen Fixation in a Temperate Perennial Grass EcosystemNARA Subscribed
Biological nitrogen (N) fixation is an important terrestrial ecosystem N input that occurs in both symbiotic and non-symbiotic associations with plants. Non-symbiotic nitrogen fixation (NSNF) has been documented in many places, including soils, but the magnitude of its inputs, along with drivers of NSNF rates, remains uncertain due to methodological challenges. We measured NSNF by applying a 15 N 2 tracer to field mesocosms th...
Impacts of Quaternary Climate History on the Biogeography of Specialized Butterflies in the Great Basin of North AmericaNARA Subscribed
Aim Dramatic Quaternary climate fluctuations impacted the evolutionary history and contemporary biogeography of many residents of the Great Basin Desert of western North America. This study investigates the historical biogeographic processes that shaped the contemporary distribution of genetic variation in a polytypic group of specialized butterflies that are residents of unique dune and playa habitats. Many of the subspecies...
Mating systems shape the population dynamics of species, influencing attributes such as effective population size and population persistence. Traditionally, genetic analysis of mating systems includes the genotyping of putative parents to determine parentage. However, for cryptic or migratory species, and those with large populations, comprehensive sampling of adults is often not feasible. One underutilised alternative is to r...
Bottom‐tow gear fisheries (trawls and dredges) produce ~24 million mt of harvest annually, representing a globally important animal‐sourced food system. While many are currently sustainably managed, growing concern over the potential for ecosystem impacts from bottom‐tow gears has increased pressure to improve these fisheries. We assembled an international working group of > 30 contributors, including fishing industry particip...
The Integration of Fire Ecology and Freshwater Ecosystems in North America: Knowledge Gaps and Research NeedsNARA Subscribed
Wildfires, unplanned fires that start and spread under the influence of weather and fuel composition, are increasing in frequency, duration, and severity across North America. While wildfires are one component of wildland fire, a broader natural process in many ecosystems, their changing behavior poses growing ecological and management challenges. Although wildfire is widely recognized as an important disturbance, empirical re...
Top‐Down and Bottom‐Up Effects on Insect Herbivores Under Global Change—A Meta‐AnalysisNARA Subscribed
Global environmental change is driving widespread insect declines, yet underlying mechanisms remain poorly understood, particularly when mediated by trophic interactions. Many studies purportedly test global change stressors on insect herbivores mediated via their host plants (bottom‐up) and natural enemies (top‐down), but we lack a comprehensive understanding of overall effects. Here, we performed a meta‐analysis of 246 paper...
Diversity and functional group composition drive biogeographic patterns in marine biogenic structural complexityNARA Subscribed
Biogenic structural complexity is a key driver of biodiversity and ecosystem functioning, yet its ecological and environmental determinants remain poorly understood across broad biogeographic scales. Here, we conducted standardized 90‐day field experiments at 16 coastal sites, spanning a 41‐degree latitudinal gradient, using naturally assembled marine fouling communities on settlement panels. We measured rugosity as our metric...
Interpretable deep learning reveals spatiotemporal MRI features of brain aging that align with neurodegenerationNARA Subscribed
Cortical thinning and atrophy are hallmarks of brain aging that have been characterized using magnetic resonance imaging (MRI). Brain aging involves many neuroanatomic features whose effects on brain structure remain unexplored. To address this challenge, we trained interpretable deep neural networks (DNNs) to estimate brain age (BA) from T 1 -weighted ( T 1 w) MRI. By identifying MRI features unapparent to humans, DNNs can fi...
SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...
Alzheimer’s disease (AD) disproportionately affects women and carriers of the apolipoprotein E ε4 allele (APOE4), yet little is known about how sex and APOE interact to influence white matter (WM) integrity during disease progression. We integrated diffusion MRI and matched blood transcriptomic data to investigate these interactions and their underlying biological mechanisms. WM microstructure was quantified using diffusion te...