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Abstract The assembly of host‐associated microbial communities is influenced by multiple factors, but the effect of microbiomes on host phenotypes is often not well understood. To address questions of food‐web effects on host microbiome assembly, we manipulated the resource environment (grass only [G] vs. grass + nutrients [GN]), competition type (intra‐ vs. inter‐specific) and density (high vs. low) forCulex restuans mosquito larvae. We predicted the microbial communities in fourth‐instar larvae would differ between these environmental treatments and that these treatments would translate into differences in the adult phenotype.Resource environment and density influenced the larval microbiome. In addition, the larval microbiome exhibited notable differences compared to the free‐living microbial communities.Resource‐driven differences in the larval samples can be attributed to Arcobacteraceae being more abundant in larvae reared in the GN treatments relative to those reared in the G treatments and Comamonadaceae being more abundant in the G treatment. Although significant, the difference in community structure between density treatments was difficult to discern. This appears to be driven by Weeksellaceae only being abundant in the high‐density, interspecific, GN treatment.Rearing larvae to adulthood under severe food limitation resulted in low survival (<25%) in both resource environments. Approximately 60% of survivors to adulthood were male. Larvae reared in the intraspecific, G treatment had the shortest development time to adulthood and emerged as the smallest adults.These results demonstrate how environmental variation can significantly alter the alpha and beta diversity of free‐living microbes, which in turn can significantly affect host phenotype and critical life history traits, such as development time, size at adulthood, and survival. These findings highlight the importance of considering environmental influences on microbiome diversity to understand and predict host outcomes, offering valuable insights for diverse applications in fields such as ecology, public health, and agriculture. 

Summary Stomatal closure during drought inhibits carbon uptake and may reduce a tree's defensive capacity. Limited carbon availability during drought may increase a tree's mortality risk, particularly if drought constrains trees' capacity to rapidly produce defenses during biotic attack.We parameterized a new model of conifer defense using physiological data on carbon reserves and chemical defenses before and after a simulated bark beetle attack in maturePinus edulisunder experimental drought. Attack was simulated using inoculations with a consistent bluestain fungus (Ophiostomasp.) ofIps confusus, the main bark beetle colonizing this tree, to induce a defensive response.Trees with more carbon reserves produced more defenses but measured phloem carbon reserves only accounted forc.23% of the induced defensive response. Our model predicted universal mortality if local reserves alone supported defense production, suggesting substantial remobilization and transport of stored resin or carbon reserves to the inoculation site.Our results show thatde novoterpene synthesis represents only a fraction of the total measured phloem terpenes inP. edulisfollowing fungal inoculation. Without direct attribution of phloem terpene concentrations to available carbon, many studies may be overestimating the scale and importance ofde novoterpene synthesis in a tree's induced defense response. 

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. 

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. 

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. 

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. 

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. 

Abstract Pinus edulis Engelm. is a short-stature, drought-tolerant tree species that is abundant in piñon-juniper woodlands throughout semiarid ecosystems of the American Southwest. P. edulis is a model species among ecophysiological disciplines, with considerable research focus given to hydraulic functioning and carbon partitioning relating to mechanisms of tree mortality. Many ecological studies require robust estimates of tree structural traits such as biomass, active sapwood area, and leaf area. We harvested twenty trees from Central New Mexico ranging in size from 1.3 to 22.7 cm root crown diameter (RCD) to derive allometric relationships from measurements of RCD, maximum height, canopy area (CA), aboveground biomass (AGB), sapwood area (AS), and leaf area (AL). Total foliar mass was measured from a subset of individuals and scaled to AL from estimates of leaf mass per area. We report a strong nonlinear relationship to AGB as a function of both RCD and height, whereas CA scaled linearly. Total AS expressed a power relationship with RCD. Both AS and CA exhibited strong linear relationships with AL (R2 = 0.99), whereas RCD increased nonlinearly with AL. We improve on current models by expanding the size range of sampled trees and supplement the existing literature for this species. Study Implications: Land managers need to better understand carbon and water dynamics in changing ecosystems to understand how those ecosystems can be sustainably used now and in the future. This study of two-needle pinon (Pinus edulis Engelm.) trees in New Mexico, USA, uses observations from unoccupied aerial vehicles, field measurements, and harvesting followed by laboratory analysis to develop allometric models for this widespread species. These models can be used to understand plant traits such biomass partitioning and sap flow, which in turn will help scientists and land managers better understand the ecosystem services provided by pinon pine across North America. 

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.