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Isolation and limited migration among populations and differences in the environments they inhabit set up conditions for population differentiation of life‐history traits, even across a regional spatial scale, such as a statewide landscape of lakes and reservoirs. Our objective was to understand how largemouth bass (Micropterus nigricans) life histories differ across a regional spatial scale (Ohio, USA) and whether environmental differences are influencing this variation. To address this, we (1) described spatial variation in largemouth bass life‐history traits, with a specific interest in potential correlations between early‐life growth and later‐life traits and (2) tested whether life‐history traits can be predicted by reservoir characteristics. We found two groups of correlated population traits: the inverse relationship of early‐life growth rate with population density and asymptotic length and the positive relationship between adult size and asymptotic length. Early‐life growth had a positive relationship (and population density and asymptotic length had a negative relationship) with littoral habitat availability and other environmental conditions expected to enhance early growth. Despite the strong influence of reservoir characteristics on life‐history traits in our analysis, the most plausible model could not give precise predictions of these life‐history traits, suggesting that the availability of data on other aspects of the populations and environments may improve our ability to understand life‐history differences. Overall, our results suggest that, even among recently separated populations, we should expect differences in growth patterns and that we cannot understand drivers of these differences without considering possible correlations in growth patterns across the lifespan. [ABSTRACT FROM AUTHOR]

Reef-building corals live in close mutualism with dinoflagellate algae (family Symbiodiniaceae), which play key roles in coral physiological performance and survival. Association patterns between host species and endosymbiont algae and their significance are still not fully understood, but they seem to affect the ability of hosts to inhabit different environments and their resilience to climate change. In this work, we used next-generation sequencing of the Internal Transcribed Spacer 2 region of ribosomal DNA to determine the diversity and composition of the Symbiodiniaceae community in Pocillopora corals from Colombia, in the Eastern Tropical Pacific (ETP). We sampled 243 colonies from four localities characterized by distinct sea surface temperature, turbidity, and proximity to the coast. Two genera of Symbiodiniaceae, Durusdinium and Cladocopium were found associated with Pocillopora mitochondrial Open Reading Frame (mtORF) types. Cladocopium latusorum was highly specific to Pocillopora mtORF type 1, while C. pacificum was found exclusively associated with Pocillopora mtORF type 3. In contrast, Durusdinium glynnii was found in both Pocillopora mtORF types. Furthermore, a Cladocopium-dominated symbiont community occurred in cooler and less turbid localities, while a Durusdinium- dominated community was found in localities with high sea surface temperature and high water turbidity, irrespective of mtORF type. These results suggest that Pocillopora mtORF lineages associate with different Symbiodiniaceae genera in response to local environmental conditions. The ability to associate with a different partner under particular environmental conditions (Pocillopora-Durusdinium combination), and also maintain a specific partnership (Cladocopium species and Pocillopora mtORF types) may be key to understanding the resilience of the genus Pocillopora on ETP coral reefs. [ABSTRACT FROM AUTHOR]

Better understanding of the responses of algal biodiversity to multiple pressures, such as climate warming and eutrophication, is a key issue in aquatic ecology. Alpha and beta diversity may have various patterns over temporal scales, especially in the Anthropocene, when external pressures became more multifaceted. However, the limited availability of historical data hampers the exploration of algal biodiversity through time.Recently, sediment DNA has emerged as a potential tool for elucidating temporal patterns in algal communities. Here, we used sediment DNA to reconstruct temporal turnover and diversity of algal communities in four remote lakes in northern China over the past 200 years. Furthermore, to distinguish the contributions of possible influencing environmental factors, we conducted structural equation modelling.Our results revealed that algal communities have experienced rapid shifts since the Anthropocene, characterized by increased alpha diversity and decreased temporal beta diversity. Warmer climate and eutrophication were associated with changes in alpha diversity, while temporal environmental variation was associated with temporal beta diversity.This study revealed opposing patterns in alpha and beta diversity for algal communities, possibly caused by warming, eutrophication and lower temporal environmental variation, respectively. While climatic factors played a major role in remote lakes with a natural environment, lakes that are more human impacted may be more structured by nutrient‐related factors.Under climate warming and intensified human activities, remote lakes may encounter complex pressures in the near future. Our findings offer valuable insights into patterns in aquatic biodiversity and possible factors underlying multiple pressures. [ABSTRACT FROM AUTHOR]

Ecosystems worldwide are increasingly being invaded by multiple species, and the rate of biological invasion is accelerating, leading to more interactions among invasive species. One such interaction that has received little attention is the phenomenon of 'serial replacement' or 'over-invasion', where an established invasive species is supplanted by a second invasive species. Understanding this interaction is important as controlling the second species could inadvertently lead to an increase in the abundance of the first species. We used a hierarchical state-space model to analyse changes in annual abundances (commercial catch-per-unit-effort) of three invasive fish species, tench (Tinca tinca), common carp (Cyprinus carpio) and redfin perch (Perca fluviatilis), in the Murray-Darling River system (MDRS), Australia between 1954–2002. Tench were present at low abundances until the mid-1970 s, before declining to the point of no commercial catch post-1989. This rapid decline coincided with a significant increase in carp abundance, suggesting that carp may have driven the tench decline through habitat modification (particularly the destruction of aquatic plants), consistent with findings from European studies that show the disappearance of tench from ponds with intensive carp farming. Redfin perch populations, were inferred to be much less impacted by the invading carp population. While carp were present in the MDRS for the duration of the study, the rapid increase in carp abundance in the early 1970 s coincided with the introduction of a specific genetic lineage—the "Boolarra strain". Our analysis provides compelling evidence of serial replacement of long-established tench by invading common carp triggered by the introduction of a novel carp strain. [ABSTRACT FROM AUTHOR]

Lizard species of wide distribution can show differences in morphology and many other characteristics, in particular in the scutelation. In this study, we analyzed the variation of 22 meristic characters between sexes and among populations of Sceloporus variabilis from the state of Hidalgo in central Mexico. The variables such as dorsal scales, scales around the body, ventral scales, femoral pores, interfemoral scales, and lamellae of the fourth digit of the hindlimbs were different among populations; the population of San Pablo Tetlapayac presented the highest average values in these variables. A positive and significant relationship between snout–vent length and the number of ventral scales was found only in the females of San Pablo Tetlapayac and Santa Catarina. The variations recorded in the present study indicate an effect of environmental variation in the pattern of the number of scales, and suggest that both environmental conditions, such as precipitation and temperature, and ecological conditions, such as substrate or microhabitats, may be influencing differences in the number and size of scales among populations. Further studies on physiology and ecomorphology are necessary to determine the direction of variations in scutelation between sexes and populations. [ABSTRACT FROM AUTHOR]

Science is as dynamic as the world around us. Our ideas continually change, as do the approaches we use to study science. Few things remain invariant in this changing landscape, but a fascination with pattern and process is one that has endured throughout the history of science. Paying homage to this long-held tradition, the 2023 Vice Presidential Symposium of the American Society of Naturalists focused on the role of pattern and process in ecology and evolution. It brought together a group of early-career researchers working on topics ranging from genetic diversity in microbes to changing patterns of species interactions in the geological record. Their work spanned the taxonomic spectrum from microbes to mammals, the temporal dimension from the Cenozoic to the present, and approaches ranging from manipulative experiments to comparative approaches. In this introductory article, I discuss how these diverse topics are linked by the common thread of elucidating processes underlying patterns and how they collectively generate novel insights into diversity maintenance at different levels of organization. [ABSTRACT FROM AUTHOR]

Despite enthusiasm for big data in the life sciences, challenges arise because of biases and incomplete data. Demographic studies often overlook dormant life stages, which can skew inferences. They also tend to focus on few populations and short time spans. We assessed omissions of seed banks in demographic studies, exploring trends across life forms, climates, and taxonomic groups. We compared 172 species (192 cases) with independent seed bank and demographic studies. Approximately 25% of the demographic studies excluded known seed bank stages. The probability of omissions was lower for annuals and shrubs and higher for perennial herbs. We found no evidence that ecoregion or phylogeny explained these omissions. Modeling choices and study designs may explain patterns of seed bank omissions. Considering more populations reduced the chance of omissions. Omissions raise concerns for ecological analyses using databases. Leveraging large data is important, but we must be careful to understand their biases and limitations. [ABSTRACT FROM AUTHOR]

Environmental variation can shape the gut microbiome, but broad/large‐scale data on among and within‐population heterogeneity in the gut microbiome and the associated environmental factors of wild populations is lacking. Furthermore, previous studies have limited taxonomical coverage, and knowledge about wild avian gut microbiomes is still scarce.We investigated large‐scale environmental variation in the gut microbiome of wild adult great tits across the species' European distribution range. We collected fecal samples to represent the gut microbiome and used the 16S rRNA gene sequencing to characterize the bacterial gut microbiome.Our results show that gut microbiome diversity is higher during winter and that there are compositional differences between winter and summer gut microbiomes. During winter, individuals inhabiting mixed forest habitat show higher gut microbiome diversity, whereas there was no similar association during summer. Also, temperature was found to be a small contributor to compositional differences in the gut microbiome. We did not find significant differences in the gut microbiome among populations, nor any association between latitude, rainfall and the gut microbiome.The results suggest that there is a seasonal change in wild avian gut microbiomes, but that there are still many unknown factors that shape the gut microbiome of wild bird populations. [ABSTRACT FROM AUTHOR]

In many species, a few individuals produce most of the next generation. How much of this reproductive skew is driven by variation among individuals in fixed traits, how much by external factors, and how much by random chance? And what does it take to have truly exceptional lifetime reproductive output (LRO)? In the past, we and others have partitioned the variance of LRO as a proxy for reproductive skew. Here we explain how to partition LRO skewness itself into contributions from fixed trait variation, four forms of "demographic luck" (birth state, fecundity luck, survival trajectory luck, and growth trajectory luck), and two kinds of "environmental luck" (birth environment and environment trajectory). Each of these is further partitioned into contributions at different ages. We also determine what we can infer about individuals with exceptional LRO. We find that reproductive skew is largely driven by random variation in lifespan, and exceptional LRO generally results from exceptional lifespan. Other kinds of luck frequently bring skewness down rather than increasing it. In populations where fecundity varies greatly with environmental conditions, getting a good year at the right time can be an alternate route to exceptional LRO, so that LRO is less predictive of lifespan. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the dynamics of early potato yield formation at 40 days depending on the weather conditions of the research years and the adaptive potential of early potato cultivars. During 2018-2024, 10 cultivars of early potatoes common in the Forest-Steppe zone were investigated in the field (Uman, 48°46′N, 30°14′E). To analyse the results obtained, the study employed generally accepted methods of field and genetic-statistical research. During the study, the number and weight of marketable tubers in the bush, the dynamics of crop formation on the 40th day after germination, and the strength of the correlation between yield and rainfall were investigated. As a result of the data obtained, the most promising cultivars were identified for early potato harvest in the Forest-Steppe region of Ukraine. It was found that this climatic zone is best suited to the cultivars Bazaliia, Tornado and Madison with a yield of 11.0-11.7 t/ha and a large weight of marketable tubers - 58-60 g. In the full ripeness phase, the most productive cultivars were Madison - 37.2 t/ha (+18.6 t/ha of control), Tornado - 34.7 t/ha (+16.1 t/ha of control), Duma and Bazaliia - 31.4 and 32.2 t/ha, respectively (+12.8 t/ha 13.6 t/ha of control, respectively). The study found that the Tornado and Madison cultivars form the largest number of marketable tubers in the bush. Analysis of the semi-ratio of plasticity and stability parameters contributed to the grouping of cultivars into intensive ones (Sanibel, Radomysl, Duma, Bazaliia and Madison had indicators bi > 1, σ2d > 0 and plastic (Povin, Vzirets, Skrabnytsia, Bernina and Tornado). As a result of the study, the most productive potato cultivars for early production were identified, which will ensure the stable development of the vegetable growing industry in the Forest-Steppe zone of Ukraine, and the calculated statistical models will allow predicting and directing the programming of potato yields. [ABSTRACT FROM AUTHOR]

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Animals migrate to access seasonally variable resources or to escape unfavorable local conditions. Partial (flexible) migration strategies offer animals a fitness trade-off in which individuals may choose whether to incur the energetic costs of migration depending on the potential benefits associated with avoiding adverse conditions. Partial migration patterns may shift because of anthropogenic land use and climate change, possibly reducing the benefits of migration and resulting in unpredictable migration cues. We examined causes, consequences, and changes in individuallevel partial migration of white-tailed deer Odocoileus virginianus by analyzing archival telemetry data (1986-2014) across four distinct populations in the Great Lakes region, North America. We hypothesized that if the costs of migration outweigh benefits, we would see migratory behavior decline. Migratory behavior declined from 75% in 1987 to 11% in 2014 independent of population identity. Annual mortality was higher for migratory white-tailed deer, whereas increasing minimum temperatures positively impacted survival but did not influence migration. Our results suggest that migratory behavior in white-tailed deer is declining over time and may be associated with declining winter severity. The loss of migratory behavior in large mammals may have ecosystem-level impacts and our study emphasizes the need to better understand and conserve these migratory traditions. [ABSTRACT FROM AUTHOR]

Background: Biological traits are mainly determined by genotype and are also influenced by environmental factors, especially in the process of adapting to different environments, corresponding phenotypic variations may occur. Even for the same animal, there may be some morphological differences due to its long-term adaptation to different habitat environments. Molar teeth are the direct contact point between animals and the environment, which are of great significance in the study of animal adaptability to different environments. Methods: To explore the relationship between the morphology of the molars (upper molars and lower molars) of tree shrews (Tupaia belangeri) and environmental variations in different regions, we applied geometric morphometric methods to measure the morphological characteristics of the molars of T. belangeri in 12 different regions of China (Hainan, Daxin, Leye, Xingyi, Xichang, Hekou, Kunming, Mengla, Dali, Tengchong, Pianma, Laboratory bred F1 generation). Result: The results showed that the morphological variations of the lower molars of T. belangeri in 12 different regions were larger, which was more suitable and reference valuable for studying the morphological differences among different geographical populations. The Principal component analysis showed that T. belangeri from 12 regions were clustered into 4 branches: Hainan was clustered into one branch, Daxin was clustered into one branch, Pianma and Tengchong were clustered into one branch and Leye, Xingyi, Hekou, Kunming, Xichang, Mengla, Dali and laboratory bred F1 generation were clustered into one branch. The thin plate spline analysis showed that deformations in the upper molars were mostly concentrated in the alveolar and dental margins. The deformations of the lower molars were mainly concentrated in the alveolar, marginal and occlusal surfaces. Multidimensional scaling showed that there were differences in molars morphology among the 12 locations, with significant variations in Hainan, Daxin, Pianma and Tengchong regions, reflecting the adaptive variation of T. belangeri to different ecological environments. The present results can provide a certain basis for the study of phenotypic adaptation in T. belangeri. [ABSTRACT FROM AUTHOR]

Temporal changes in environmental conditions may play a major role in the year-to-year variation in fitness consequences of behaviours. Identifying environmental drivers of such variation is crucial to understand the evolutionary trajectories of behaviours in natural contexts. However, our understanding of how environmental variation influences behaviours in the wild remains limited. Using data collected over 14 breeding seasons from a collared flycatcher (Ficedula albicollis) population, we examined the effect of environmental variation on the relationship between survival and risk-taking behaviour, a highly variable behavioural trait with great evolutionary and ecological significance. Specifically, using annual recapture probability as a proxy of survival, we evaluated the specific effect of predation pressure, food availability, and mean temperature on the relationship between annual recapture probability and risk-taking behaviour (measured as flight initiation distance [FID]). We found a negative trend, as the relationship between annual recapture probability and FID decreased over the study years and changed from positive to negative. Specifically, in the early years of the study, risk-avoiding individuals exhibited a higher annual recapture probability, whereas in the later years, risk-avoiders had a lower annual recapture probability. However, we did not find evidence that any of the considered environmental factors mediated the variation in the relationship between survival and risk-taking behaviour. [ABSTRACT FROM AUTHOR]

Across animal systems, abiotic environmental features, including timing of seasonal events and weather patterns, affect fitness. An individual's degree of social integration also has fitness consequences, but we lack an understanding of how abiotic features relate to patterns of individual sociality. A deeper understanding of this relationship could be developed from studying systems where these two links with fitness have already been identified. We explored the relationship between individual social behavior and seasonal timing, seasonal length, and weather patterns. We used social network analysis on a sixteen-year dataset of a wild population of hibernating yellow-bellied marmots (Marmota flaviventer). We fit a series of generalized linear mixed models and found that longer growing seasons before winter hibernation and longer winters were associated with increased individual sociality in the following spring. However, later snowmelt was associated with decreased sociality that spring. We found no relationship between individual sociality and various measures of precipitation and temperature. This suggests that seasonal timing and length may be a more important driver of sociality than weather patterns in this system, both as a lag and contemporary effect. Seasonal timing and length may mediate the opportunity or intensity of social interactions. The entwined relationships between the seasonal schedule and weather, and the seemingly contradictory role of winter length and snowmelt, suggests the timing of seasons and its relationship with sociality is complex and further exploration of environment-sociality relationships is required across taxa. Significance statement: While the adaptive benefits of social behavior are well studied, less is known about how features of the abiotic environment drive variation in individual social behavior. Given increasing stochasticity in the timing of seasonal events and weather patterns, mapping the environment-sociality relationship will provide important insights to the drivers of sociality in the wild. This is particularly salient for species most vulnerable to climate and environmental change, such as seasonal hibernators, like yellow-bellied marmots (Marmota flaviventer). We found that features of seasonal duration were positively associated with increased sociality, whereas the timing of seasonal onset was negatively associated. This work provides empirical evidence towards an important gap in the behavioral ecology literature. [ABSTRACT FROM AUTHOR]

Carotenoid-dependent ornaments can reflect animals' diet and foraging behaviors. However, this association should be spatially flexible and variable among populations to account for geographic variation in optimal foraging behaviors. We tested this hypothesis using populations of a marine predator (the brown booby, Sula leucogaster) that forage across a gradient in ocean depth in and near the Gulf of California. Specifically, we quantified green chroma for two skin traits (foot and gular color) and their relationship to foraging location and diet of males, as measured via global positioning system tracking and stable carbon isotope analysis of blood plasma. Our three focal colonies varied in which foraging attributes were linked to carotenoid-rich ornaments. For gular skin, our data showed a shift from a benthic prey-green skin association in the shallow waters in the north to a pelagic prey-green skin association in the deepest waters to the south. Mean foraging trip duration and distance of foraging site from coast also predicted skin coloration in some colonies. Finally, brown booby colonies varied in which trait (foot versus gular skin color) was associated with foraging metrics. Overall, our results indicate that male ornaments reflect quality of diet and foraging–information that may help females select mates who are adapted to local foraging conditions and therefore, are likely to provide better parental care. More broadly, our results stress that diet-dependent ornaments are closely linked to animals' environments and that we cannot assume ornaments or ornament signal content are ubiquitous within species, even when ornaments appear similar among populations. [ABSTRACT FROM AUTHOR]

In recent years considerable interest has been generated in a new approach known as resist–accept–direct, or RAD, for managing ecosystems in the face of climate change. Under RAD, strategic responses to climate change are described in terms of three broad categories: resisting climate transformation, accepting the transformation and continuing to manage as best one can, and directing the transformed system toward novel ecological conditions. In particular, the potential for integrating RAD and adaptive management has been broadly considered, though absent a decision‐making framework needed for implementation.We propose a hierarchical decision scheme for RAD that accounts for strategy selection among the three RAD options, as well as adaptive decision making within each option. We use stochastic models and uncertainties about ecosystem processes to account for the dynamics of climate‐transformed ecosystems, and show how these features can be used to inform RAD strategies. Operationally, the approach involves decisions at two levels: one level involves choosing a policy for each strategy, and the second level involves deciding which strategy has the greatest policy value.The structure described here extends recent work in climate change adaptation, by including Markovian decisions under climate change, strategy‐specific policies, and value functions for assessing and selecting RAD strategies. We provide a hierarchical accounting of decisions and responses, and develop rules for the timing of those decisions.Combining RAD and adaptive management can help to organize thinking about ecological conservation under climate change, and focus attention on mechanisms for making decisions. We believe the structure presented here can facilitate conservation efforts under the non‐stationary climate conditions we are sure to face for the foreseeable future. [ABSTRACT FROM AUTHOR]

Plant responses to multiple environmental conditions in the habitat are characterized by intra-species variety. Ferula assa-foetida L. is a native medical plant in Iran, which has a wide range of therapeutic and pharmacological properties. The objective of the current study was to identify changes in phenolic content, antioxidant capacity and essential oil (EO) composition in different tissues (leaf, flower and fruit) of three populations of F. assa-foetida L. (Sarbisheh, Nehbandan, located in South Khorasan province of Iran). The results showed that total phenolic content (TPC), total flavonoid content (TFC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity in the leaves of Sarbisheh were higher than in other treatments. The amount of TPC, TFC and DPPH scavenging activity in leaves was higher than in other tissues in the Sarbisheh population, increasing by 31 and 70%, 41 and 20%, 8 and 13%, respectively, over that of flowers and fruits. The main EO compounds of leaves were α -pinene (11.86–13.56%), β -pinene (6.80–7.99%), bornyl acetate (15.80–17.33%). The main EO constitutes of flowers were Z-propenyl-sec-butyldisulfide (10.12–12.4%), eco-fenchyl acetate (10.87–12.4%), myrcisticin (13.43–15.87%) and α -bisabolol (11.23–13.76%). The primary compounds of fruit EO were β -pinene (9.32–11.26%), (Z)-1-propenyl sec butyldisulf (17.54–18.87%) and (E)-1-propenyl sec butyldisulf (28.32–30.02%). The agglomerative hierarchical clustering showed that three distinguished clusters were identified for population, where Nehbandan and Qaen had the higher similarity and Sarbisheh completely differed from the two ones. Different plant tissues contain varying types of chemicals, with leaves exhibiting higher levels of phenolic content and antioxidant capacity. This characteristic can be beneficial for industries such as food and pharmaceuticals. [ABSTRACT FROM AUTHOR]

As wildlife is increasingly affected by environmental change, identifying how vital rates vary with ecological factors is essential to predict the consequences of environmental perturbations on wild population dynamics. We explored the effects of habitat constraints on the demographic and life history patterns of two Barbary macaque (Macaca sylvanus) populations living in two contrasted habitats in Algeria. Using 11 years of field data, we estimated age‐specific survival rates of females and of infants of both sexes, as well as female reproduction rates. We investigated how these vital rates were influenced by both intra‐ and inter‐habitat environmental variations. We parameterized age‐structured female‐only transition matrices and conducted a prospective analysis to estimate the contribution of each vital rate to the populations' asymptotic growth rates (λ). A retrospective analysis (LTRE, Life Table Response Experiment) was also conducted to determine how each vital rate contributed to the observed differences in λ between populations. The macaques exhibited common patterns of survival and reproduction (low rates at young ages, and then high and stable until a decrease at old ages), with first evidence of both actuarial and reproductive senescence. Both populations were growing. In both populations, adult and immature survival had the highest elasticities, and remained stable in changing environmental conditions. By contrast, infant survival and female reproduction had low elasticities, and varied more with environmental variations. As Barbary macaque habitats are increasingly degrading, we provide robust estimates of their vital rates with conservation implications, in particular to predict population responses to anthropogenic perturbations. [ABSTRACT FROM AUTHOR]

Introgression is pervasive across the tree of life but varies across taxa, geography, and genomic regions. However, the factors modulating this variation and how they may be affected by global change are not well understood. Here, we used 200 genomes and a 15-y site-specific environmental dataset to investigate the effects of environmental variation and mating system divergence on the magnitude of introgression between a recently diverged outcrosser-selfer pair of annual plants in the genus Clarkia. These sister taxa diverged very recently and subsequently came into secondary sympatry where they form replicated contact zones. Consistent with observations of other outcrosser-selfer pairs, we found that introgression was asymmetric between taxa, with substantially more introgression from the selfer to the outcrosser. This asymmetry was caused by a bias in the direction of initial F1 hybrid formation and subsequent backcrossing. We also found extensive variation in the outcrosser's admixture proportion among contact zones, which was predicted nearly entirely by interannual variance in spring precipitation. Greater fluctuations in spring precipitation resulted in higher admixture proportions, likely mediated by the effects of spring precipitation on the expression of traits that determine premating reproductive isolation. Climate-driven hybridization dynamics may be particularly affected by global change, potentially reshaping species boundaries and adaptation to novel environments. [ABSTRACT FROM AUTHOR]

The spatiotemporal allocation of activity is fundamental to how organisms balance energetic intake and predation risk. Activity patterns fluctuate daily and seasonally, and they are proximately affected by exogenous and endogenous conditions. For birds, flight activity is often necessary for relocating between foraging patches but is energetically expensive and can increase mortality risk. Hunted species may have to adjust their behavior and activity patterns to minimize anthropogenic mortality risk. We used hourly locations from 336 GPS-marked mallards Anas platyrhynchos to examine how hunting pressure affected flight activity in response to weather conditions and habitat availability during winter in western Tennessee, USA. Mallards were more likely to fly during crepuscular times, particularly dusk, across winter months. Mallards conducted more flights after shooting hours when habitat availability increased during open hunting season; conversely, mallard flights decreased with increasing habitat availability when hunters were present on the landscape. Mallards were least active during periods open to hunting. However, indicators of approaching inclement weather (i.e. increased wind speed, precipitation, and decreasing barometric pressure) increased flights during periods open to hunting. Mallard flights decreased at lower temperatures except when hunting season was closed, wherein mallards increased nighttime flights. Flight activity was directly influenced by hunting disturbance which constrained when and how mallards reacted to environmental and habitat conditions. An understanding of the temporal shifts in waterfowl flight patterns can be used by natural resource managers to better manage stakeholder satisfaction and expectations. [ABSTRACT FROM AUTHOR]

Objective: To determine the phenotypic plasticity between fertilized (F) and unfertilized (UF) Q. variabilis seedlings developed in a nursery using small, medium, and large seeds. Design/methodology/approach: By analyzing the phenotypic traits of growth (height and diameter at root collar) and root and stem dry biomass, plasticity indices and allocation patterns were assessed, and phenotypic traits in which the interaction effect of the seedling fertilization and seed size was observed. Results: The results showed significant differences (p-value≥0.05) in the growth and biomass traits except for the root dry biomass, and significant differences were found both in the fertilization and seed size factors and in the fertilization and seed size interaction in phenotypic traits. For plasticity, all traits showed marked changes in response to the nutrient application, and small seeds had the highest plasticity indices. With respect to phenotypic change indices, medium seeds reached the highest values (0.94 for height and 0.92 for diameter). Large seeds recorded the highest index for root dry biomass (1.01), and medium seeds had the highest values of plasticity for stem dry biomass (0.81). Allometric differences were observed (intercepts were 1.8374 and 3.4956, and slopes were 4.0943 and 1.7038 for UF and F seedlings, respectively), and variations in the study factors (fertilization and seed size). Limitations on study/implications: In order to improve the survival of plants in the field it is necessary to use seeds with high quality. Findings/conclusions: Fertilization of Q. variabilis seedlings increases their biomass production, which allows for greater growth and survival compared to unfertilized ones. [ABSTRACT FROM AUTHOR]

The genes ECERIFERUM1 (CER1) and ECERIFERUM3 (CER3) encode the biosynthesis of alkane waxes, a key component of the plant cuticle. To study the evolution of CER1 and CER3 in a highly diverse group of eucalypts, we performed a genome-wide survey using recently released genome assemblies of 28 Myrtaceae species, with 22 species from the main eucalypt lineage and 6 non-eucalypt Myrtaceae tree species. We manually annotated 250 genes and pseudogenes, identifying a near-ubiquitous single copy of CER3 and 2 to 10 CER1 gene copies per Myrtaceae species. Phylogenetic analysis suggested that copy number variation in eucalypts is due to multiple tandem duplication events, both ancient (shared by all Myrtaceae species studied) and relatively recent (present only in eucalypts). Inter-chromosomal translocations were discovered for both CER1 and CER3, along with recurrent loss of often the same CER1 introns in the WAX2 domain, the domain that is essential for wax production. Despite the varied environments occupied by the eucalypt species in this study, we did not find statistically significant associations between intra-genic structural changes or CER1 copy number and aspects of the environment they occupy (including aridity). The challenge is now to explain the species-specific evolutionary histories that contributed to the observed variation in CER1 and the extent to which it may contribute to the adaptability of eucalypts. [ABSTRACT FROM AUTHOR]

The Amazon forests are under threat from multiple human land uses, but the effect of the different types of land uses on environmental heterogeneity and the α- and β-diversity of aquatic insects remains unclear. We studied how habitat features of streams and aquatic insect diversity in the orders Ephemeroptera, Plecoptera, and Trichoptera (hereafter, EPT) responded to different land uses in the Brazilian Amazon. By sampling and analyzing EPT community data from 83 streams distributed in multiple land uses and land covers, we found that the impact of forest conversion was mixed. Despite contiguous and fragmented forest streams presenting similar environmental conditions, they differed in insect diversity metrics. α-diversity was highest in contiguous forest streams and EPT β-diversity was higher in streams surrounded by livestock farming and primary oil palm plantations. The association between land use and habitat degradation may not be so direct, mainly when streams are inserted into or surrounded by forest fragments. This has important implications because politicians and policymakers often regard forest fragments as degraded landscapes, to justify their conversion to other land uses. Our study shows that forest fragments must be protected and restored to reduce the risks of degrading the ecological condition of Amazonian streams. [ABSTRACT FROM AUTHOR]

Environmental perturbations are encountered by microorganisms regularly and will require metabolic adaptations to ensure an organism can survive in the newly presenting conditions. In order to study the mechanisms of metabolic adaptation in such conditions, various experimental and computational approaches have been used. Genome-scale metabolic models (GEMs) are one of the most powerful approaches to study metabolism, providing a platform to study the systems level adaptations of an organism to different environments which could otherwise be infeasible experimentally. In this review, we are describing the application of GEMs in understanding how microbes reprogram their metabolic system as a result of environmental variation. In particular, we provide the details of metabolic model reconstruction approaches, various algorithms and tools for model simulation, consequences of genetic perturbations, integration of '-omics' datasets for creating context-specific models and their application in studying metabolic adaptation due to the change in environmental conditions. [ABSTRACT FROM AUTHOR]

Clinopodium nepeta subsp. spruneri is an aromatic herb with a mint-oregano flavor, used in Mediterranean regions in traditional medicine. The aerial parts of the plant are rich in essential oil that has antioxidant, antimicrobial and anti-inflammatory properties as well as insecticidal activity. The aim of our work was to determine the yield and composition of the essential oil of the plant, in relation to the harvest season and cultivation method, i.e., outdoor, greenhouse and in vitro culture, using gas chromatography-mass spectrometry (GC-MS) as an analytical tool. Essential oil yield fluctuated similarly in outdoor and greenhouse plants during the year (0.9–2.6%), with higher percentages (2.1–2.6%) in the hottest periods June–October (flowering stage) and April (vegetative stage), and was similar to the yield in in vitro plants (1.7%). More compounds were identified in the oil of outdoor and greenhouse plants (35) compared to that of in vitro plants (21), while the main compounds were the same, i.e., pulegone (13.0–32.0%, highest in February–April, 15.0% in vitro), piperitenone oxide (3.8–31.8%, lowest in February, 34.2% in vitro), piperitone epoxide (4.6–16.4%, highest in February, 15.5% in vitro), D-limonene (2.1–8.8%, lowest in February, 10.0% in vitro), isomenthone (2.3–23.0%, highest in February, 4.6% in vitro), germacrene D (1.9–6.5% highest in December-April, 2.9% in vitro) and dicyclogermacrene (2.1–5.3%, highest in December–April, 5.2% in vitro). Therefore, greenhouse and in vitro cultures were equally efficient in yielding essential oil and its constituents as outdoor cultivation, while in outdoor and greenhouse cultivations, the harvest season, mainly due to the prevailing ambient temperatures, affected the essential oil yield and its percentage composition. [ABSTRACT FROM AUTHOR]

This document provides a comprehensive overview of the role of mosquito microbiota in the transmission of vector-borne diseases. It emphasizes the influence of environmental factors and human activities on disease risk and vector competence. The document includes a literature review and original research articles that explore the factors affecting mosquito microbiota composition and its implications for public health. It discusses the interplay between seasonality and land cover on mosquito abundance and microbial communities, as well as the effects of competition and Wolbachia infection on host fitness and vector competence. The document also highlights the role of the mycobiome in providing temporary niches for bacterial survival and alternative transmission routes. It explores regulatory mechanisms in mosquito host selection behavior and the potential of disrupting bacterial communication for control purposes. Additionally, it discusses the presence of bacteria in mosquito saliva and their potential to colonize mammalian hosts, suggesting the possibility of mosquitoes serving as vectors of bacterial infection. Overall, this document contributes to our understanding of the interactions between vectors, their microbiota, and the transmission of pathogens. [Extracted from the article]

Ziziphus lotus is an underappreciated natural genetic resource widespread in Algeria. This study aimed to compare the fruit phytochemical composition of nine populations of Z. lotus from different areas to highlight its diversity. Fruits were harvested from the semiarid, dry steppe and Saharan stages. Primary and secondary metabolites and minerals contents were determined. Significant variations in the fruit phytochemical composition between populations of Z. lotus and between pulp and seeds were recorded. Z. lotus is dry fruit with 8.768 ± 0.449 to 13.468 ± 1.303% water in pulp and 6.7 to 12.12% in seeds. Significantly higher values were recorded in the fruit pulp for sugar (35.25 to 48.87%), phosphorus (63.114 to 155.269 mg 100−1g), sodium (34.8 to 56.91 ppm), calcium (91.78 to 382.69 ppm), β-carotene (36.4 to 46 μg g−1), lycopene (59.15 to 100.25 μg g−1) and chlorophyll a (3.6 to 7.2 μg g−1) contents. Seeds had much higher protein (8.37 to 27.75%), lipid (35.39 to 48.01%), potassium (125.874 to 325.408 mg. 100−1 g), polyphenol (439.465 to 1349.46 mg.GAE.100 g−1), flavonoid (83.908 to 98.259 mg.QE.100 g−1), tannins (55.268 to 277.94 mg.GAE.100 g−1) and chlorophyll b (11.2 to 30.4 μg g−1) contents. Bougtob, Boghar and Mougheul populations had higher primary metabolites and mineral values. Oued Nougued, Maarif and Mougheul populations were the richest in phenolic compounds. Oued Nougued, Maarif and Mougheul populations had more liposoluble pigments. This research is the beginning of investigating the variety of Z. lotus as phylogenetic sources. Further comparative investigations over a larger distribution region and further study of variations in the composition in fruit composition using GC-MS are needed. [ABSTRACT FROM AUTHOR]

While researchers have investigated mating decisions for decades, gaps remain in our understanding of how behaviour influences social mate choice. We compared spatial cognitive performance and food caching propensity within social pairs of mountain chickadees inhabiting differentially harsh winter climates to understand how these measures contribute to social mate choice. Chickadees rely on specialized spatial cognitive abilities to recover food stores and survive harsh winters, and females can discriminate among males with varying spatial cognition. Because spatial cognition and caching propensity are critical for survival and likely heritable, pairing with a mate with such enhanced traits may provide indirect benefits to offspring. Comparing the behaviour of social mates, we found that spatial cognitive performance approached a significant correlation within pairs at low, but not at high elevation. We found no correlation within pairs in spatial reversal cognitive performance at either elevation; however, females at high elevation tended to perform better than their social mates. Finally, we found that caching propensity correlated within pairs at low, while males cached significantly more food than their social mates at high elevations. These results suggest that cognition and caching propensity may influence social mating decisions, but only in certain environments and for some aspects of cognition. [ABSTRACT FROM AUTHOR]

Tidal rivers are peculiar, yet vastly unknown. These rivers are characterized by dynamic tides without saline intrusion. This unusual environmental configuration should affect the biological communities present in these habitats. Therefore, our main goal was to identify the temporal patterns of the zooplankton communities in tidal rivers and the influence of the environment on these patterns. We applied an approach that investigates the local diversity and turnover of species (i.e., alpha and temporal beta diversities, respectively) to disentangle the temporal dynamics of individual taxonomic groups at tidal rivers. Our findings evidenced that periods of high diversity are always followed by periods of low diversity. We suggest that the temporal variation in the resources exploited by zooplankton, specifically algal biomass, is the major factor driving this temporal pattern. Periods of high rainfall led to species homogenization, whereas periods of high insolation and wind speed (i.e., dry periods) led to heterogenization. Moreover, we evidenced that protozoa was the group with the highest alpha diversity, and its species turnover was constrained by seasonality in a similar way to that of rotifers, with both groups undergoing homogenization during rainy periods. Here, we describe the zooplankton community dynamics in tidal rivers over time, which is a scale often disregarded in ecological studies, and suggest that future research should consider temporal variation associated with extensive spatial replication to disentangle ecological patterns. [ABSTRACT FROM AUTHOR]

The occurrence of within-population variation in germination behavior and associated traits such as seed size has long fascinated evolutionary ecologists. In annuals, unpredictable environments are known to select for bet-hedging strategies causing variation in dormancy duration and germination strategies. Variation in germination timing and associated traits is also commonly observed in perennials and often tracks gradients of environmental predictability. Although bet-hedging is thought to occur less frequently in long-lived organisms, these observations suggest a role of bet-hedging strategies in perennials occupying unpredictable environments. We use complementary analytical and evolutionary simulation models of within-individual variation in germination behavior in seasonal environments to show how bet-hedging interacts with fluctuating selection, life-history traits, and competitive asymmetries among germination strategies. We reveal substantial scope for bet-hedging to produce variation in germination behavior in long-lived plants, when "false starts" to the growing season results in either competitive advantages or increased mortality risk for alternative germination strategies. Additionally, we find that lowering adult survival may, in contrast to classic bet-hedging theory, result in less spreading of germination by decreasing density-dependent competition. These models extend insights from bet-hedging theory to perennials and explore how competitive communities may be affected by ongoing changes in climate and seasonality patterns. [ABSTRACT FROM AUTHOR]

The gut microbiota have important consequences for host biological processes and there is some evidence that they also affect fitness. However, the complex, interactive nature of ecological factors that influence the gut microbiota has scarcely been investigated in natural populations. We sampled the gut microbiota of wild great tits (Parus major) at different life stages allowing us to evaluate how microbiota varied with respect to a diverse range of key ecological factors of two broad types: (1) host state, namely age and sex, and the life history variables, timing of breeding, fecundity and reproductive success; and (2) the environment, including habitat type, the distance of the nest to the woodland edge, and the general nest and woodland site environments. The gut microbiota varied with life history and the environment in many ways that were largely dependent on age. Nestlings were far more sensitive to environmental variation than adults, pointing to a high degree of flexibility at an important time in development. As nestlings developed their microbiota from one to two weeks of life, they retained consistent (i.e., repeatable) among‐individual differences. However these apparent individual differences were driven entirely by the effect of sharing the same nest. Our findings point to important early windows during development in which the gut microbiota are most sensitive to a variety of environmental drivers at multiple scales, and suggest reproductive timing, and hence potentially parental quality or food availability, are linked with the microbiota. Identifying and explicating the various ecological sources that shape an individual's gut bacteria is of vital importance for understanding the gut microbiota's role in animal fitness. [ABSTRACT FROM AUTHOR]

Ecologists have put forward many explanations for coexistence, but these are only partial explanations; nature is complex, so it is reasonable to assume that in any given ecological community, multiple mechanisms of coexistence are operating at the same time. Here, we present a methodology for quantifying the relative importance of different explanations for coexistence, based on an extension of the Modern Coexistence Theory. Current versions of Modern Coexistence Theory only allow for the analysis of communities that are affected by spatial or temporal environmental variation, but not both. We show how to analyze communities with spatiotemporal fluctuations, how to parse the importance of spatial variation and temporal variation, and how to measure everything with either mathematical expressions or simulation experiments. Our extension of Modern Coexistence Theory shows that many more species can coexist than originally thought. More importantly, it allows empiricists to use realistic models and more data to better infer the mechanisms of coexistence in real communities. [ABSTRACT FROM AUTHOR]

Conservation and management of biological systems involves decision‐making over time, with a generic goal of sustaining systems and their capacity to function in the future. We address four persistent and difficult conservation challenges: (1) prediction of future consequences of management, (2) uncertainty about the system's structure, (3) inability to observe ecological systems fully, and (4) nonstationary system dynamics. We describe these challenges in terms of dynamic systems subject to different sources of uncertainty, and we present a basic Markovian framework that can encompass approaches to all four challenges. Finding optimal conservation strategies for each challenge requires issue‐specific structural features, including adaptations of state transition models, uncertainty metrics, valuation of accumulated returns, and solution methods. Strategy valuation exhibits not only some remarkable similarities among approaches but also some important operational differences. Technical linkages among the models highlight synergies in solution approaches, as well as possibilities for combining them in particular conservation problems. As methodology and computing software advance, such an integrated conservation framework offers the potential to improve conservation outcomes with strategies to allocate management resources efficiently and avoid negative consequences. [ABSTRACT FROM AUTHOR]

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Background: Grafting is a horticultural practice used widely across woody perennial crop species to fuse together the root and shoot system of two distinct genotypes, the rootstock and the scion, combining beneficial traits from both. In grapevine, grafting is used in nearly 80% of all commercial vines to optimize fruit quality, regulate vine vigor, and enhance biotic and abiotic stress-tolerance. Rootstocks have been shown to modulate elemental composition, metabolomic profiles, and the shape of leaves in the scion, among other traits. However, it is currently unclear how rootstock genotypes influence shoot system gene expression as previous work has reported complex and often contradictory findings. Results: In the present study, we examine the influence of grafting on scion gene expression in leaves and reproductive tissues of grapevines growing under field conditions for three years. We show that the influence from the rootstock genotype is highly tissue and time dependent, manifesting only in leaves, primarily during a single year of our three-year study. Further, the degree of rootstock influence on scion gene expression is driven by interactions with the local environment. Conclusions: Our results demonstrate that the role of rootstock genotype in modulating scion gene expression is not a consistent, unchanging effect, but rather an effect that varies over time in relation to local environmental conditions. [ABSTRACT FROM AUTHOR]

Populations and chromosomal races of a species often show variation in life-history characteristics due to phylogeny and environmental factors. We analysed variation in snout–vent length (SVL) and reproductive variables, such as minimum SVL at sexual maturity, litter size and embryo volume in females of the Sceloporus grammicus lizard complex, which includes seven chromosomal races as well as hybrid zones among different combinations of races (F5, F5 + 6, potential but unverified F5 + 6, F6, FM1, FM2, FM2 × F5 hybrid zone, FM3, LS and unverified SGG). The SGG, F5 and LS females were larger than F6 and FM3 females. Females with non-vitellogenic follicles and vitellogenic follicles were smaller than females with embryos. The SVL of females containing embryos varied among chromosomal races, the largest being the same as indicated above, but the smallest was the FM2 × F5 hybrid zone. Litter size was similar among chromosomal races (5.8 embryos), while embryo volumes varied among them. Two patterns of reproductive activity were found: seasonal and continuous reproduction. Our results showed the influence of environmental factors of each locality, which supports the ecological hypothesis. The use of chromosomal races did not reveal a significant phylogenetic effect, because allozyme and molecular data show only small pairwise genetic distances among the S. grammicus populations on the Mexican Plateau. [ABSTRACT FROM AUTHOR]

Lonicera caeruleabrix is a perennial shrub native to North America, Europe and Asia. It produces dark blue berries known as honeyberries or haskap berries which are produced commercially in several territories including Canada, Japan, Russia and Poland. Plants are suited to UK environments, but it is yet to be widely commercially developed in the UK. In the present work, quality and nutritional traits of six honeyberry cultivars grown in Scotland were compared with other commonly grown berry fruits (strawberry, raspberry, blueberry, blackberry, blackcurrant) to aid the identification of environmentally stable, high‐quality honeyberry cultivars suitable for UK cultivation. Differences were observed in fruit quality variables (soluble solids, titratable acidity and Brix/acid ratios) between honeyberry cultivars. Three of six cultivars examined exhibited notable variation in soluble solids dependent on harvest year with 'Aurora' and 'Strawberry Sensation' having consistently high oBrix values. Titratable acidity exhibited cultivar differences and there was limited variation over harvest years. 'Aurora' exhibited consistently high oBrix/titratable acidity ratio reflected by high glucose and fructose content. Honeyberry fruit had good nutritional profile relative to other soft fruits with higher polyphenol and anthocyanin content than strawberry, blueberry, blackberry and raspberry, manifested in greater antioxidant capacity. The major anthocyanins in aqueous honeyberry fruit extracts were cyanidin, pelargonidin and peonidin glycosides. These findings indicate that L. caerulea represents a crop suitable for UK cultivation capable of producing high quality fruit with a valuable nutritional profile relative to other soft fruits. Cultivars exhibit significant differences in fruit quality and nutritional profile as well as harvest consistency and growers should consider this when establishing new plantations. [ABSTRACT FROM AUTHOR]

Intraspecific variability (IV) has been proposed to explain species coexistence in diverse communities. Assuming, sometimes implicitly, that conspecific individuals can perform differently in the same environment and that IV increases niche overlap, previous studies have found contrasting results regarding the effect of IV on species coexistence. We aim at showing that the large IV observed in data does not mean that conspecific individuals are necessarily different in their response to the environment and that the role of high‐dimensional environmental variation in determining IV has largely remained unexplored in forest plant communities. We first used a simulation experiment where an individual attribute is derived from a high‐dimensional model, representing "perfect knowledge" of individual response to the environment, to illustrate how large observed IV can result from "imperfect knowledge" of the environment. Second, using growth data from clonal Eucalyptus plantations in Brazil, we estimated a major contribution of the environment in determining individual growth. Third, using tree growth data from long‐term tropical forest inventories in French Guiana, Panama and India, we showed that tree growth in tropical forests is structured spatially and that despite a large observed IV at the population level, conspecific individuals perform more similarly locally than compared with heterospecific individuals. As the number of environmental dimensions that are well quantified at fine scale is generally lower than the actual number of dimensions influencing individual attributes, a great part of observed IV might be represented as random variation across individuals when in fact it is environmentally driven. This mis‐representation has important consequences for inference about community dynamics. We emphasize that observed IV does not necessarily impact species coexistence per se but can reveal species response to high‐dimensional environment, which is consistent with niche theory and the observation of the many differences between species in nature. [ABSTRACT FROM AUTHOR]

When investigating metacommunity dynamics, functional differences among species are often assumed to be as important as environmental differences between sites in determining β‐diversity. However, few studies have examined the influence of functional diversity on β‐diversity. We examine the relative importance of regional functional diversity partitioned by niche dimensions and environmental variation in structuring taxonomic β‐diversity of stream fishes using a large dataset of stream fish assemblages (hereafter, simply β‐diversity). We predicted that both functional diversity and environmental variation play a role in determining β‐diversity.We tested this prediction by modelling the patterns of stream fish β‐diversity as a function of environmental variation, functional diversity and γ‐richness across 10,220 sites for 329 fish species using a series of conceptual path models.Environmental variation consistently affected β‐diversity across all models, whereas functional diversity and γ‐richness influenced β‐diversity only in some models. We show that including relevant trait differences among species in path models can improve their ability to explain β‐diversity, suggesting that functional traits influence β‐diversity.The ability of path models to explain β‐diversity varied depending on the trait grouping included in the model, demonstrating that specific path models representing different niche dimensions can improve the ability of a model to explain β‐diversity. In addition, parsing traits into different niche dimensions revealed alternative patterns of functional diversity–β‐diversity relationships that otherwise would have been missed.The selection of relevant traits and linked niche dimensions is critical for detecting relationships between functional diversity and β‐diversity. Using traits associated with different niche dimensions allows for the identification of niche dimensions most strongly associated with species sorting and the detection of patterns missed by focusing on a single niche dimension. Determining the niche dimensions that influence β‐diversity could provide insights into the processes driving biodiversity and metacommunity dynamics, improving our ability to conserve or restore aquatic communities. [ABSTRACT FROM AUTHOR]

Thermal variability is a key driver of ecological processes, affecting organisms and populations across multiple temporal scales. Despite the ubiquity of variation, biologists lack a quantitative synthesis of the observed ecological consequences of thermal variability across a wide range of taxa, phenotypic traits and experimental designs. Here, we conduct a meta-analysis to investigate how properties of organisms, their experienced thermal regime and whether thermal variability is experienced in either the past (prior to an assay) or present (during the assay) affect performance relative to the performance of organisms experiencing constant thermal environments. Our results—which draw upon 1712 effect sizes from 75 studies—indicate that the effects of thermal variability are not unidirectional and become more negative as mean temperature and fluctuation range increase. Exposure to variation in the past decreases performance to a greater extent than variation experienced in the present and increases the costs to performance more than diminishing benefits across a broad set of empirical studies. Further, we identify life-history attributes that predictably modify the ecological response to variation. Our findings demonstrate that effects of thermal variability on performance are context-dependent, yet negative outcomes may be heightened in warmer, more variable climates. [ABSTRACT FROM AUTHOR]

Thermal variability is a key driver of ecological processes, affecting organisms and populations across multiple temporal scales. Despite the ubiquity of variation, biologists lack a quantitative synthesis of the observed ecological consequences of thermal variability across a wide range of taxa, phenotypic traits and experimental designs. Here, we conduct a meta-analysis to investigate how properties of organisms, their experienced thermal regime and whether thermal variability is experienced in either the past (prior to an assay) or present (during the assay) affect performance relative to the performance of organisms experiencing constant thermal environments. Our results—which draw upon 1712 effect sizes from 75 studies—indicate that the effects of thermal variability are not unidirectional and become more negative as mean temperature and fluctuation range increase. Exposure to variation in the past decreases performance to a greater extent than variation experienced in the present and increases the costs to performance more than diminishing benefits across a broad set of empirical studies. Further, we identify life-history attributes that predictably modify the ecological response to variation. Our findings demonstrate that effects of thermal variability on performance are context-dependent, yet negative outcomes may be heightened in warmer, more variable climates. [ABSTRACT FROM AUTHOR]

Pacific sardine (Sardinops sagax) is a commercially important species and supports important fisheries in the Northwest Pacific Ocean (NPO). Understanding the habitat distribution patterns of Pacific sardine is of great significance for fishing ground prediction and stock management. In this study, both single-algorithm and ensemble distribution models were established through the Biomod2 package for Pacific sardine by combining the species occurrence data, sea surface temperature (SST), sea surface height (SSH), sea surface salinity (SSS) and chlorophyll-a concentration (Chla) in the NPO during the main fishing season (June–November) from 2015 to 2020. The results indicated that the key environmental variables affecting the habitat distribution of Pacific sardine were the SSH and SST. The suitable habitat area for Pacific sardine showed significant monthly changes: the suitable habitat range in June was larger than that in July and August, while the suitable habitat range gradually increased from September to November. Furthermore, the monthly geometric centers of habitat suitability index (HSI) for Pacific sardine presented a counterclockwise pattern, gradually moving to the northeast from June, and then turning back to the southwest from August. Compared with single-algorithm models, the ensemble model had higher evaluation metric values and better spatial correspondence between habitat prediction and occurrence records data, which indicated that the ensemble model can provide more accurate prediction and is a promising tool for potential habitat forecasting and resource management. [ABSTRACT FROM AUTHOR]

Substantial variation in the environment directly causes remodeling of the colonized gut microbiota, controlling community diversity, and functions in the host to tune-up their adaptive states. However, the mechanisms of microbial community assembly in response to environmental changes remain unclear, especially in endangered ruminants. In this study, we analyzed the microbial communities of 37 fecal samples collected from captive and wild Alpine musk deer (Moschus chrysogaster) to characterize the complexity and assembly processes using 16S rRNA gene sequencing. We found significantly di erent diversities and compositions of gut microbiota among both groups associated with di erent living environments. Heterogeneous selection was the predominant factor regulating the gut microbiota community under similar climatic conditions, indicating that microbial community assemblywas largely driven by deterministicmechanisms. The species co-occurrence network showed complex and tight connections with a higher positive correlation in the wild environment. Moreover, the captive group exhibited significant differences in chemoheterotrophy and fermentation compared with the wild group, but the opposite was observed in animal parasites or symbionts, which might be closely related to diet, energy supply, and healthcare of animals. This study provides a framework basis and new insights into understanding gut microbiota in different environments. [ABSTRACT FROM AUTHOR]

Introduced social insects can be highly invasive outside of their native range. Around the world, the introduction and establishment of the eusocial bumblebee Bombus terrestris (L. 1758) (Hymenoptera: Apidae) has negatively impacted native pollinators and ecosystems. Understanding how morphological variation is linked to environmental variation across invasive ranges can indicate how rapidly species may be diverging or adapting across novel ranges and may assist with predicting future establishment and spread. Here we investigate whether B. terrestris shows morphological variation related to environmental variation across the island of Tasmania (Australia) where it was introduced three decades ago. We collected 169 workers from 16 sites across Tasmania and related relative abundance and morphology to landscape-wide climate, land use, and vegetation structure. We found weak morphological divergence related to environmental conditions across Tasmania. Body size of B. terrestris was positively associated with the percentage of urban land cover, a relationship largely driven by a single site, possibly reflecting high resource availability in urban areas. Proboscis length showed a significant negative relationship with the percentage of pasture. Wing loading and local abundance were not related to the environmental conditions within sites. Our results reflect the highly adaptable nature of B. terrestris and its ability to thrive in different environments, which may have facilitated the bumblebee's successful invasion across Tasmania. [ABSTRACT FROM AUTHOR]

Population genetic analysis of variation at five neutral microsatellite loci for Mediterranean mussels (Mytilus galloprovincialis) from 18 sites along the eastern Adriatic Sea revealed little or no spatial variation. In contrast, seascape genetics analysis revealed a pronounced locus‐specific gradient in allelic and genotypic frequencies across the study region. At a sixth locus, MGE7, the frequencies of two alleles, MGE7243 and MGE7249, were strongly associated, negatively and positively, respectively, with a single environmental variable – minimum salinity (minSAL). The frequency of the MGE7243/243 homozygous genotype was strongly negatively associated with minSAL, whereas the frequencies of the MGE7246/249 and the MGE7249/249 genotypes were strongly positively correlated with minSAL. Interpretation of these pronounced gradients is confounded by the fact that minSAL and another environmental variable, maximum sea surface temperature (maxSST), are highly correlated (R = −.911) and are therefore not necessarily acting independently. BLAST searches of the MGE7 locus against M. galloprovincialis whole genome shotgun sequence returned an alignment with contig mg10_S01094 (accession UYJE01010330.1) and 7 predicted M. galloprovincialis proteins VDI82194.1 ‐ VDI82200.1. Conserved domain searches revealed a similar structure to the transcriptional regulator Msx2‐interacting protein. The BLASTp search also returned significant alignments to Msx2‐interacting proteins in Mytilus coruscus, Crassostrea virginica, and Haliotis rubra. The existence of the MGE7 gradient highlights the role that environmental variation may play in retarding gene flow among wild M. galloprovincialis populations, and also how the success of collection of young mussels (spat) from one site and their transfer to another site (the farm) may be influenced by a single factor such as minSAL or maxSST on a localized scale. [ABSTRACT FROM AUTHOR]

Habitat quality can have far‐reaching effects on organismal fitness, an issue of concern given the current scale of habitat degradation. Many temperate upland streams have reduced nutrient levels due to human activity. Nutrient restoration confers benefits in terms of invertebrate food availability and subsequent fish growth rates. Here we test whether these mitigation measures also affect the rate of cellular ageing of the fish, measured in terms of the telomeres that cap the ends of eukaryotic chromosomes. We equally distributed Atlantic salmon eggs from the same 30 focal families into 10 human‐impacted oligotrophic streams in northern Scotland. Nutrient levels in five of the streams were restored by simulating the deposition of a small number of adult Atlantic salmon Salmo salar carcasses at the end of the spawning period, while five reference streams were left as controls. Telomere lengths and expression of the telomerase reverse transcriptase (TERT) gene that may act to lengthen telomeres were then measured in the young fish when 15 months old. While TERT expression was unrelated to any of the measured variables, telomere lengths were shorter in salmon living at higher densities and in areas with a lower availability of the preferred substrate (cobbles and boulders). However, the adverse effects of these habitat features were much reduced in the streams receiving nutrients. These results suggest that adverse environmental pressures are weakened when nutrients are restored, presumably because the resulting increase in food supply reduces levels of both competition and stress. [ABSTRACT FROM AUTHOR]

Avoiding inbreeding is considered a key driver of dispersal evolution, and dispersal distances should be especially important in mediating inbreeding risk because the likelihood of mating with relatives decreases with dispersal distance. However, a lack of direct data on dispersal distances has limited empirical tests of this prediction, particularly in the context of the multiple selective forces that can influence dispersal. Using the headwater stream salamander Gyrinophilus porphyriticus , we tested whether spatial variation in environmental conditions leads to differences in dispersal distances, resulting in spatial variation in the effect of dispersal on inbreeding risk. Using capture-recapture and population genomic data from five streams, we found that dispersal distances were greater in downstream reaches than upstream reaches. Inbreeding risk trended lower for dispersers than nondispersers in downstream reaches but not in upstream reaches. Furthermore, stream reaches did not differ in spatial patterns of individual relatedness, indicating that variation in inbreeding risk was in fact due to differences in dispersal distances. These results demonstrate that environmentally associated variation in dispersal distances can cause the inbreeding consequences of dispersal to vary at fine spatial scales. They also show that selective pressures other than inbreeding avoidance maintain phenotypic variation in dispersal, underscoring the importance of addressing alternative hypotheses in dispersal research. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding variations in the morphology and age of animals along a geographical gradient may aid in our comprehension of the evolution of these animals. In this view, we studied variation in the age and body size of Andrew's toad (Bufo andrewsi) across 31 populations along a geographical gradient. The results revealed that along with a decrease in the annual mean temperature, the age structure increased, whereas body size did not indicate an increasing trend, showing no support for Bergmann's rule. Precipitation seasonality negatively correlated with longevity and mean age, whereas precipitation of the driest month positively correlated with body size. Moreover, we also found that UV-B seasonality positively correlated with age structure traits and body size. The present study provided critical cues that explain the considerable variability observed in the ecogeographic patterns among Andrew's toads. Environmental variation likely modifies the life-history traits of vertebrates. As ectothermic vertebrates, it is possible that the body size of amphibians is impacted by environmental conditions. Here, we firstly quantified age and body size variation in the Andrew's toad (Bufo andrewsi) across the Hengduan Mountains. Then, we examined the environmental correlates of this variation based on the literature and our unpublished data on the age and body size of the Andrew's toad from 31 populations distributed in southwestern China. Although our analysis revealed significant variations in age and body size across B. andrewsi populations, neither latitude nor altitude correlated with this variability in age and body size. We found that age at sexual maturity, mean age, and longevity increased with decreasing annual mean temperature, whereas age at sexual maturity increased with decreasing temperature seasonality, implying that temperature was a crucial habitat characteristic that modulated age structure traits. Moreover, we revealed positive associations between age structure and UV-B seasonality, and negative relationships between both mean age and longevity and precipitation seasonality. We also found that body size increased with increasing precipitation in the driest month and UV-B seasonality. However, body size did not covary with temperature, signifying no support for Bergmann's rule. These findings help us to understand amphibians' abilities to adapt to environmental variation, which is particularly important in order to provide a theorical basis for their conservation. [ABSTRACT FROM AUTHOR]

Wind speed can have multifaceted effects on organisms including altering thermoregulation, locomotion, and sensory reception. While forest cover can substantially reduce wind speed at ground level, it is not known if animals living in forests show any behavioural responses to changes in wind speed. Here, we explored how three boreal forest mammals, a predator and two prey, altered their behaviour in response to average daily wind speeds during winter. We collected accelerometer data to determine wind speed effects on activity patterns and kill rates of free-ranging red squirrels (n = 144), snowshoe hares (n = 101), and Canada lynx (n = 27) in Kluane, Yukon from 2015 to 2018. All 3 species responded to increasing wind speeds by changing the time they were active, but effects were strongest in hares, which reduced daily activity by 25%, and lynx, which increased daily activity by 25%. Lynx also increased the number of feeding events by 40% on windy days. These results highlight that wind speed is an important abiotic variable that can affect behaviour, even in forested environments. [ABSTRACT FROM AUTHOR]