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AviList: a unified global bird checklist
No full textUniversally recognized scientific names for organisms are necessary for accurate and efficient communication. Incongruence in taxonomic treatments results in situations where one name is used for different entities or one entity is known by different names, with negative consequences for conservation, science, trade, legislation, law enforcement, and education, leading to discord among stakeholders and confusion among users. Within the ornithological community taxonomic incongruence among four widely adopted global bird checklists has led to calls for the development of a single unified global avian taxonomy or checklist. Here we introduce AviList, a comprehensive, collaborative and evolving effort towards developing a unified global avian taxonomy, spearheaded by representatives of most current global checklists and many major regional authorities, and supported by the International Ornithologists’ Union (IOU), BirdLife International and the Cornell Lab of Ornithology. AviList version 2025, the first version, was officially launched on 11 June 2025 and is available online as a comprehensive, searchable public-access database. It recognizes 11,131 bird species in 2376 genera, 252 families and 46 orders. This global effort has resolved over 1000 species-level taxonomic incongruences among existing checklists. With AviList’s launch, the IOC World Bird List and the Clements Checklist of Birds of the World have ceased any independent taxonomic updates, while BirdLife International is in the process of total alignment, leading to a harmonization in the classification underpinning a number of major bird projects, including eBird, Macaulay Library, Merlin Bird ID and the IUCN Red List. Adoption of AviList will improve inter-operability across global biodiversity, molecular, ecological and spatial databases (e.g. GBIF). Strong governance of AviList will ensure it is a “living” document that is regularly updated by a global community of bird taxonomists as new scientific advances are made, with positive impacts for conservation, academia and human society. It is hoped that AviList will support and encourage taxonomic science by identifying areas where further research is most needed, and that it will provide a blueprint for taxonomic authorities in other organismic groups endeavoring to achieve taxonomic harmonization
Leucocytozoon Prevalence Differs by Sex in Louisiana Wild Turkeys (Meleagris gallopavo)
No full textEastern wild turkeys (Meleagris gallapovo silvestris) in Louisiana have not fully recovered since their decline in the mid-20th century, despite multiple conservation management efforts. Wild turkeys are susceptible to Leucocytozoon infection and also serve as reservoirs of Leucocytozoon parasites. In this study, we tested for Haemosporidian infections (Haemoproteus, Plasmodium, and Leucocytozoon) in 106 different blood samples collected from hunted and live-trapped turkeys in Louisiana using PCR and sequencing of amplicons. Haemoproteus was the most prevalent genus (92%) and had the highest species diversity among the three genera. One-third of our samples were positive for Leucocytozoon infection, significantly less than Haemoproteus but similar to Plasmodium. Male turkeys were more likely to be infected by Leucocytozoon parasites than females. We detected two Leucocytozoon species, Leucocytozoon schoutedeni and Leucocytozoon sabrazesi, the latter possibly being the first detection in North America. There were four times as many turkeys infected with all three genera of Haemosporidia than uninfected turkeys. Last, we present a case study of an emaciated wild turkey in Louisiana; its death was attributed to Leucocytozoon infection. Future research into the pathology of Leucocytozoon infections will clarify whether Leucocytozoon parasites may contribute to population declines in turkeys through mortality or negative reproduction impacts, and whether one sex is more tolerant to Leucocytozoon infection than the other
Nanoparticles alter the nature and strength of intraploidy and interploidy interactions in plants
No full textEngineered nanoparticles have profound impacts on organisms, yet there is limited understanding of how nanoparticle exposure shapes species interactions that are key to natural community dynamics. By growing plants of the same (intraploidy) and different ploidy levels (interploidy) of Fragaria in axenic microcosms, we examined the influence of nanoparticles on species interactions in polyploid and diploid plants. Under copper oxide (CuO) nanoparticle exposure, polyploids experienced reduced competition and a shift towards facilitation, when growing with both polyploids (the effect of polyploids on polyploids measured by the relative interaction index, RII8x,8x) and diploids (the effect of diploids on polyploids, RII8x,2x). This reduction in competitive interactions in polyploids, in line with the stress gradient hypothesis, was primarily driven by nanoscale effects. In contrast, the strength of competitive interactions (RII8x,8× and RII8x,2x) increased under CuO bulk particles compared to control conditions. Different from polyploids, diploids experienced neutral interactions (RII2x,2x and RII2x,8x) under both nanoparticles and bulk particles. These findings highlight ploidy-specific interaction dynamics and the need to consider species interactions when predicting organismal responses to nanoparticle pollution in ecological communities, providing critical insights for conservation strategies and sustainable nanotechnology applications
Thiol-Acrylate Gel Systems For Frontal Polymerization
No full textA trithiol-triacrylate gel system for frontal polymerization was explored to establish the gelation time, shelf life, and frontal kinetics. The free-standing gels were created by triethylamine-catalyzed Michael addition of trimethylolpropane tris(3-mercaptopropionate) to trimethylolpropane triacrylate such that sufficient acrylate functional groups were left unreacted to allow free-radical frontal polymerization with the initiator 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane (Luperox 231). Systems with gelation times between 30 and 60 min that support frontal polymerization after up to 28 days of storage were achieved. The front velocity was found to depend on the 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane concentration. However, the amount of triethylamine, which was used to catalyze gel formation, did not significantly affect front velocity. The gel diameter and addition of milled carbon fiber (Zoltek px35) affected the front velocity. Cracks during frontal polymerization were reduced when Zoltek px35 was added to the formulation, which also increased the mechanical strength. Complex geometries of free-standing gels were successfully polymerized. This system is potentially useful in situations where molding and reshaping gels are required prior to frontal polymerization, as well as enabling the ability to examine how mechanical forces like stretching and compression can affect front kinetics
The quest for habitats in the outer Solar System and how to protect exotic pristine environments
No full textThe search for life within our Solar System and beyond has been a key motivation for space exploration since its inception. These efforts have focused on specific celestial bodies located within the habitable zone . Mars has long been a primary target for exploration, but the large moons of the gas giants Jupiter and Saturn have also emerged as fascinating astrobiological candidates, offering promising conditions for habitability and the potential for life to emerge and persist. To ensure safe and sustainable exploration of these bodies, the 114 countries that signed the Outer Space Treaty in 1967 assigned the Committee on Space Research (COSPAR) the task of creating planetary protection guidelines. These guidelines are designed to align with the Treaty and prevent the harmful effects of both forward and backward contamination. While the planetary protection policy established by the COSPAR Panel on Planetary Protection (PPP) is not legally binding, it is internationally recognized and accompanied by implementation guidelines for all stakeholders. The PPP focuses on the biological exchange that occurs during solar system exploration, including the chemical evolution and the origin and development of life forms. It examines the potential impacts of contamination from Earth-based organisms on the environments of planets other than Earth and natural satellites, and also considers the risk of contaminating Earth with materials returned from space that may carry extraterrestrial life (cosparhq.cnes.fr/scienti_c-structure/panels/panel-on-planetary-protection-ppp/). The COSPAR Policy is grounded in the latest scientific understanding and adheres to the principle that COSPAR\u27s planetary protection guidelines should facilitate, not hinder, Solar System exploration by being regularly reviewed and updated in line with new scientific discoveries and the evolving demands of space exploration. In this paper, we review our current knowledge of the possible habitats in the outer Solar System and their current and future safe and sustainable exploration (for example, with missions like Juice, Europa Clipper and Dragonfly) to secure access to unique and primordial information on the origin and evolution of life on our own planet
Dynamics of Meandering River Cutoffs and Post-Cutoff Sedimentation
No full textMeander cutoffs are pivotal events in the life cycle of rivers, abruptly adjusting flow fields and reshaping riparian environments. The consequences of cutoffs extend beyond geomorphology, influencing aquatic ecosystems, sediment storage within the floodplain, nutrient and contaminant cycling, and risks to human infrastructure. Yet, research of cutoffs has not produced a clear conceptual understanding of the persistence of oxbow lakes, and the dynamics of post-cutoff planform change that aligns with the observations of cutoff events on a global scale. This research aims to use satellite imagery to further clarify our understanding of the post-cutoff morphometrics and processes that constrain the persistence of oxbow lakes, the migration of neck cutoff bends, and the terrestrialization of the post-neck cutoff channels.
A global dataset of 218 cutoff events documented within four decades of Landsat imagery was used to study the terrestrialization of abandoned channels and track active channels following cutoff. Results show that in the first 10 years after cutoff, chute cutoffs infill with sediment and terrestrialize at twice the rate of neck cutoffs, and the distance of the active channel from the abandoned channel was greater for neck cutoffs. The difference between the two styles of cutoff is novel and suggests for the first time that migration of the active channel following cutoff is a key control on oxbow sedimentation. From that larger dataset, 137 neck cutoffs were further analyzed for migration of their post-cutoff bends. Results show that most neck cutoffs result in high curvature bends, migration of the post-cutoff bend is over six times greater than the average migration of the reach, and the style of migration is influenced by the maximum curvature of the cutoff bend. A detailed analysis of six neck cutoffs using high resolution Planet-imagery showed sedimentation locations are influenced by inherited flow, and the length ratio and curvature of the cutoff bend influence the cutoff bar shape.
The results of this study serve to adjust and refine the classical models used to describe post-cutoff sedimentation and planform morphology, highlighting cutoffs as dynamic, fundamental processes that reshape meandering rivers, govern oxbow lifespans, and influence floodplain evolution
Unveiling the Interfacial Reconstruction Mechanism Enabling Stable Growth of the Delafossite PdCoO2 on Al2O3 and LaAlO3
No full textDelafossites, composed of noble metal (A+) and strongly correlated sublayers (BO2-), form natural superlattices with highly anisotropic properties. These properties hold significant promise for various applications, but their exploitation hinges on the successful growth of high-quality thin films on suitable substrates. Unfortunately, the unique lattice geometry of delafossites presents a significant challenge to thin-film fabrication. Different delafossites grow differently, even when deposited on the same substrate, ranging from successful epitaxy to complete growth suppression. These variations often lack a clear correlation to obvious causes like lattice mismatch. Unidentified stabilization mechanisms appear to enable growth in certain cases, allowing these materials to form stable thin films or act as buffer layers for subsequent delafossite growth. This study employs advanced scanning transmission electron microscopy techniques to investigate the nucleation mechanism underlying the stable growth of PdCoO2 films on Al2O3 and LaAlO3 substrates grown via molecular-beam epitaxy. Our findings reveal the presence of a secondary phase within the substrate surface that stabilizes the films. This mechanism deviates from the conventional understanding of strain relief mechanisms at oxide heterostructure interfaces and differs significantly from those observed for Cu-based delafossites
Layer-dependent spin-resolved electronic structure of ferromagnetic triple-layered ruthenate Sr4Ru3 O10
No full textHigh-resolution angle- and spin-resolved photoemission spectroscopy (ARPES) of the triple-layered ruthenate Sr4Ru3O10 reveals features of the electronic structure that extend our understanding of the layered strontium ruthenates. The spectra near the Fermi energy are very different from the nonmagnetic analogues Sr2RuO4 and Sr3Ru2O7 with distinct Fermi surfaces for wide electronlike minority spin bands around the zone center and narrow holelike majority spin Fermi surface contours around the zone corners. The most dramatic results are two narrow spectral peaks ∼30 meV below the Fermi level, a spin-minority holelike band at the Brillouin zone center, and a spin-majority saddle-band van Hove singularity at the zone edge, which exhibits almost 100% spin polarization at low temperature, and a strong temperature dependent coherence-incoherence crossover attributed to Hund metal correlations. Quantitative comparison of the ARPES to spin-polarized density functional theory (DFT) calculations identify the specific antibonding and nonbonding orbital origins of the narrow bands, with a prediction of different spatial localization in the central and outer layers. This is shown to be consistent with experimental ARPES multizone matrix element intensity variations, and implicates outer-layer-specific control of the in-plane metamagnetism. The renormalization of the bands relative to the mean-field DFT, the demonstration of spin-polarized oxygen bands, and of spin-minority and spin-majority band-crossing hybridization provide a more complete picture of the magnetism which displays aspects of both delocalized and local moment behavior
Using Food as a Fun and Effective Teaching Tool in Preschool
No full textFood is one of the most engaging, hands-on materials for preschool classrooms. This article highlights research from the Food FAN Academy (Furr, 2023), which demonstrates how food can be used as a teaching tool across early childhood learning environments. Practical strategies are provided for preschool teachers, including detailed lesson plans that connect to early math, science, literacy, and social development. The article emphasizes the importance of using everyday materials, cultural inclusivity, and active learning methods to promote curiosity, health awareness, and foundational skills in young learners
From Storage Closet to Creative Oasis: How to Set Up an Atelier and Outdoor Space for Young Children
No full textCreating meaningful learning spaces doesn\u27t always require a big budget or new construction—sometimes, all it takes is a storage closet, a bit of imagination, and a deep respect for children’s ideas. In this article, I’ll share how we transformed underutilized spaces at our school into a vibrant atelier and outdoor classroom and offer tips to help you do the same