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  1. Addressing climate change and biodiversity loss will be the defining ecological, political, and humanitarian challenge of our time. Alarmingly, policymakers face a narrowing window of opportunity to prevent the worst impacts, necessitating complex decisions about which land to set aside for biodiversity preservation. Yet, our ability to make these decisions is hindered by our limited capacity to predict how species will respond to synergistic drivers of extinction risk. We argue that a rapid integration of biogeography and behavioral ecology can meet these challenges because of the distinct, yet complementary levels of biological organization they address, scaling from individuals to populations, and from species and communities to continental biotas. This union of disciplines will advance efforts to predict biodiversity’s responses to climate change and habitat loss through a deeper understanding of how biotic interactions and other behaviors modulate extinction risk, and how responses of individuals and populations impact the communities in which they are embedded. Fostering a rapid mobilization of expertise across behavioral ecology and biogeography is a critical step toward slowing biodiversity loss. 
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    Free, publicly-accessible full text available April 11, 2024
  2. Global amphibian populations are declining rapidly, due largely to infectious diseases such as chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). The Herpetology Department at the Sam Noble Museum has screened for Bd prevalence among amphibian communities across Oklahoma for over five years, providing ongoing data about the disease’s prevalence and distribution. Recently, the museum partnered with other Oklahomans through a citizen science project allowing participants to sample their local amphibian communities for Bd. Our project targeted K–12 students in Oklahoma to promote curiosity in science and to foster an interest in pursuing career paths in science, technology, engineering, and mathematics (STEM). The multi-year baseline citizen science dataset we obtained shows a lower Bd prevalence compared to samples collected from trained researchers. In this study, we juxtapose the two datasets and make observations on the feasibility of the citizen science program. Results from the program suggest that kit return rates were average for a project of this scale, and many participants could correctly identify amphibian species. Our findings indicate that the citizen science initiative is successful in increasing statewide amphibian disease sampling range and heightening the public’s awareness of this global amphibian epidemic. 
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    Free, publicly-accessible full text available January 6, 2024
  3. Abstract

    Given the rapidly changing landscapes of habitats across the globe, a sound understanding of host-associated microbial communities and the ecoevolutionary forces that shape them is needed to assess general organismal adaptability. Knowledge of the symbiotic endogenous microbiomes of most reptilian species worldwide remains limited. We sampled gut microbiomes of geckos spanning nine species and four genera in the Philippines to (i) provide baseline data on gut microbiota in these host species, (ii) test for significant associations between host phylogenetic relationships and observed microbial assemblages, potentially indicative of phylosymbiosis, and (iii) identify correlations between multiple ecoevolutionary factors (e.g. species identity, habitat tendencies, range extents, and maximum body sizes) and gut microbiomes in Philippine gekkonids. We recovered no significant association between interspecific host genetic distances and observed gut microbiomes, providing limited evidence for phylosymbiosis in this group. Philippine gekkonid microbiomes were associated most heavily with host species identity, though marked variation among conspecifics at distinct sampling sites indicates that host locality influences gut microbiomes as well. Interestingly, individuals grouped as widespread and microendemic regardless of host species identity displayed significant differences in alpha and beta diversity metrics examined, likely driven by differences in rare OTU presence between groups. These results provide much needed insight in host-associated microbiomes in wild reptiles and the ecoevolutionary forces that structure such communities.

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  4. Abstract

    Injectable hydrogels are increasingly explored for the delivery of cells to tissue. These materials exhibit both liquid‐like properties, protecting cells from mechanical stress during injection, and solid‐like properties, providing a stable 3D engraftment niche. Many strategies for modulating injectable hydrogels tune liquid‐ and solid‐like material properties simultaneously, such that formulation changes designed to improve injectability can reduce stability at the delivery site. The ability to independently tune liquid‐ and solid‐like properties would greatly facilitate formulation development. Here, such a strategy is presented in which cells are ensconced in the pores between microscopic granular hyaluronic acid (HA) hydrogels (microgels), where elasticity is tuned with static covalent intra‐microgel crosslinks and flowability with mechanosensitive adamantane‐cyclodextrin (AC) inter‐microgel crosslinks. Using the same AC‐free microgels as a 3D printing support bath, the location of each cell is preserved as it exits the needle, allowing identification of the mechanism driving mechanical trauma‐induced cell death. The microgel AC concentration is varied to find the threshold from microgel yielding‐ to AC interaction‐dominated injectability, and this threshold is exploited to fabricate a microgel with better injection‐protecting performance. This delivery strategy, and the balance between intra‐ and inter‐microgel properties it reveals, may facilitate the development of new cell injection formulations.

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  5. Tennessen, J (Ed.)
    Abstract Non-mammalian model organisms have been essential for our understanding of the mechanisms that control development, disease, and physiology, but they are underutilized in pharmacological and toxicological phenotypic screening assays due to their low throughput in comparison with cell-based screens. To increase the utility of using Drosophila melanogaster in screening, we designed the Whole Animal Feeding FLat (WAFFL), a novel, flexible, and complete system for feeding, monitoring, and assaying flies in a high-throughput format. Our 3D printed system is compatible with inexpensive and readily available, commercial 96-well plate consumables and equipment. Experimenters can change the diet at will during the experiment and video record for behavior analysis, enabling precise dosing, measurement of feeding, and analysis of behavior in a 96-well plate format. 
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    Free, publicly-accessible full text available January 18, 2024
  6. Abstract

    Dormant propagules can provide a rapid colonization source for temporary aquatic habitats and set the trajectory for community dynamics, yet the egg banks of stormwater management systems have received little attention. We asked which species hatched from the sediment of drainage ditches in Champaign County, IL, and found bdelloid rotifers and ostracods (Heterocypris incongruens) to be the most common taxa. These sites also are colonized by mosquitoes, and we established laboratory experiments to examine interspecific interactions between common co‐occurring taxa.Culex restuanslarvae were reared in the presence or absence ofH. incongruensat two intra‐ and interspecific densities (20 or 40 total individuals) and their survivorship to adulthood, development time to adulthood, adult body size, and sex ratio were determined. Survival forCx. restuanswas significantly lower at high larval density than at low larval density in both treatments.Culex restuanslarvae reared in the presence ofH. incongruenshad a shorter development time to adulthood and emerged as larger adults compared to those reared in the absence ofH. incongruens. The sex ratios in theH. incongruenstreatments were female‐biased whereas those in theCulex‐only treatments were male‐biased. These differences may have epidemiological implications, as only female mosquitoes serve as disease vectors. Our results emphasize the importance of understanding interspecific interactions in influencing larval mosquito development traits.

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  7. Many processes of biological diversification can simultaneously affect multiple evolutionary lineages. Examples include multiple members of a gene family diverging when a region of a chromosome is duplicated, multiple viral strains diverging at a “super-spreading” event, and a geological event fragmenting whole communities of species. It is difficult to test for patterns of shared divergences predicted by such processes because all phylogenetic methods assume that lineages diverge independently. We introduce a Bayesian phylogenetic approach to relax the assumption of independent, bifurcating divergences by expanding the space of topologies to include trees with shared and multifurcating divergences. This allows us to jointly infer phylogenetic relationships, divergence times, and patterns of divergences predicted by processes of diversification that affect multiple evolutionary lineages simultaneously or lead to more than two descendant lineages. Using simulations, we find that the method accurately infers shared and multifurcating divergence events when they occur and performs as well as current phylogenetic methods when divergences are independent and bifurcating. We apply our approach to genomic data from two genera of geckos from across the Philippines to test if past changes to the islands’ landscape caused bursts of speciation. Unlike previous analyses restricted to only pairs of gecko populations, we find evidence for patterns of shared divergences. By generalizing the space of phylogenetic trees in a way that is independent from the likelihood model, our approach opens many avenues for future research into processes of diversification across the life sciences. 
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  8. Despite multiple recent field studies, herpetological species diversity of the Romblon Island Group in the central Philippines—particularly Sibuyan Island—has remained underestimated. Recently, we investigated the diversity of the herpetofauna of Mount Guiting-Guiting Natural Park, based on an elevational transect (10–1557 m a.s.l.). Our surveys resulted in a total of 47 species of amphibians and reptiles, including 14 new island records and one atypical occurrence of a snake species recorded for the first time from a high elevation (939 m a.s.l). These new records constitute a notable increase (21%) in Sibuyan’s herpetological species diversity as compared to surveys from a decade ago. We also provide updates of the taxonomy and identification of species endemic to this island (e.g., members of the genera Platymantis Günther, 1858, Brachymeles Duméril & Gibron, 1839, and Pseudogekko Taylor, 1922), and discuss the importance of continued surveys and field-derived data to inform conservation status assessments of Sibuyan’s unique assemblage of amphibians and reptiles. 
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  9. The study of animal personality is a growing field that has applications for welfare of animals living in captive settings. We measured personality traits (activity, exploration, and neophobia) in Texas horned lizards (Phrynosoma cornutum) living in human care before they were released to their natal habitat as part of a headstart program. We found evidence of consistent inter-individual differences in activity and exploration, but not neophobia. We also identified a positive correlation between activity and exploration, such that more active lizards were also more likely to explore a novel environment. These results suggest that Texas horned lizards have individual differences in response to their environment, which can inform husbandry decisions. Extensions of this work could also have implications for conservation of Texas horned lizards and for headstart programs focused on reptiles. 
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