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AbstractOrganismal divergence can be driven by differential resource use and adaptation to different trophic niches. Variation in diet is a major factor shaping the gut microbiota, which is crucial for many aspects of their hosts' biology. However, it remains largely unknown how host diet diversity affects the gut microbiota, and it could be hypothesized that trophic niche width is positively associated with gut microbiota diversity. To test this idea, we sequenced the 16S ribosomal RNA gene from intestinal tissue of 14 threespine stickleback populations from lakes of varying size on Vancouver Island, Canada, that have been shown to differ in trophic niche width. Using lake size as a proxy for trophic ecology, we found evidence for higher gut microbiota uniqueness among individuals from populations with broader trophic niches. While these results suggest that diet diversity might promote gut microbiota diversity, additional work investigating diet and gut microbiota variation of the same host organisms will be necessary. Yet our results motivate the question of how host population diversity (e.g., ecological, morphological, genetic) might interact with the gut microbiota during the adaptation to ecological niches.

Here, we describe "obelisks," a class of heritable RNA elements sharing several properties: (1) apparently circular RNA ∼1 kb genome assemblies, (2) predicted rod-like genome-wide secondary structures, and (3) open reading frames encoding a novel "Oblin" protein superfamily. A subset of obelisks includes a variant hammerhead self-cleaving ribozyme. Obelisks form their own phylogenetic group without detectable similarity to known biological agents. Surveying globally, we identified 29,959 distinct obelisks (clustered at 90% sequence identity) from diverse ecological niches. Obelisks are prevalent in human microbiomes, with detection in ∼7% (29/440) and ∼50% (17/32) of queried stool and oral metatranscriptomes, respectively. We establish Streptococcus sanguinis as a cellular host of a specific obelisk and find that this obelisk's maintenance is not essential for bacterial growth. Our observations identify obelisks as a class of diverse RNAs of yet-to-be-determined impact that have colonized and gone unnoticed in human and global microbiomes. [Display omitted] • Obelisks are a phylogenetically distinct group of microbiome-associated, viroid-like RNAs • Found globally in diverse niches, obelisks also occur in human stool and oral microbiomes • The human oral bacterium Streptococcus sanguinis SK36 harbors a distinct "obelisk- S.s " • Under replete growth conditions, obelisk- S.s appears to be disposable for SK36 growth Obelisks are widespread RNA-based agents found in diverse environmental and human-associated microbiomes. These apparently unbranched and circular RNAs represent a previously uncharacterized class of genetic elements. [ABSTRACT FROM AUTHOR]

This study aimed to explore the interrelationships among plant species, their ecological niches, and community stability by establishing and investigating long-term biodiversity monitoring plots. Understanding the succession patterns of these communities can provide a foundation for biodiversity conservation, forest resource management, and vegetation restoration in forest parks. A 1 hm² plot was selected within the broad-leaved forest in the Xin’anjiang Forest Park for dynamic monitoring. Based on their importance values, the study focused on the top 13 dominant woody species. Ecological niche widths (BS, BL) and niche overlap indices(Oik) were calculated. Statistical methods including variance ratio, Chi-square test χ2, Pearson’s coefficient of correlation, and Spearman’s rank-order correlation coefficient were used to analyze the relationship between species niche overlap indices and species associations. The study found no significant correlation between the ranking of importance values and niche breadths. Schima superba presented the highest importance value, followed by Quercus glauca, Castanopsis sclerophylla, and Lithocarpus glabra. These four species demonstrated a competitive edge in the community’ s resource dynamics, displaying a high degree of niche convergence among the dominant species. The collective linkage of the 13 dominant species demonstrated a marked positive correlation. The χ2 test results indicated strong relative independence among species, with only one species pair showing significant linkage, indicating loose connectivity. The Pearson correlation coefficient presented a significant level of 24. 4%, while the Spearman rank correlation coefficient showed that only 28. 2% of species pairs had significant linkage. The niche overlap index was positively correlated with species connectivity. In summary, the overall community was determined to be in a stable state and is currently progressing toward the mid-to-late stage of positive succession. It is recommended that appropriate thinning of denser stands, particularly of Castanopsis sclerophylla and Cunninghamia lanceolata, be conducted to promote the formation of a high-quality forest community while strictly protecting the current forest. [ABSTRACT FROM AUTHOR]

We experimentally tested whether the presence of a free benthic predator (Odonata naiads) alters the displacement time, the position occupied in the water column, and the proportion of food consumed by benthic and nektonic tadpoles. The presence of predators did not influence the displacement time or the proportion of food consumed by any of the two species. In the presence of predators, benthic tadpoles avoided the benthic microhabitat, increasing their time in the middle of the water column. This behavior was unexpected since the previous studies indicate that the morphology of benthic tadpoles restricts them to the bottom of water bodies. We, thus, hypothesize that such a drastic behavior change was a consequence of the real risk of predation to which the tadpoles were exposed. Our results are in accordance with the threat-sensitivity hypothesis, in which prey behave flexibly when exposed to different degrees of predation threats. Nektonic tadpoles, however, slightly increased their permanence in the water column in the presence of the same benthic predators. Therefore, we provide support for the hypothesis that predators induce greater behavioral changes in prey that exhibit patterns of microhabitat use similar to theirs. [ABSTRACT FROM AUTHOR]

Ecological niche models (ENMs) are an essential modelling technique in biodiversity prediction and conservation and are frequently used to forecast species responses to global changes. Classic species‐level models may show limitations as they assume species homogeneity, neglecting intraspecific variation. Composite ENMs allow the integration of intraspecific variation by combining intraspecific‐level ENMs, capturing individual environmental responses over the species' geographic range. While recent studies suggest that accounting for intraspecific variation improves model predictions, we currently lack methods to test the significance of the improvement. Here, we propose a null model approach that randomises observed intraspecific structures as an appropriate baseline for comparison. We illustrate this approach by comparing predictive performance of a species‐level ENM to composite ENMs for European beech Fagus sylvatica. To investigate the influence of spatial lineage structure, we tested all models against the same withheld data to allow comparison across models based on five common performance metrics. We found that the species‐level ENM expressed higher overall performance (i.e. AUC, TSS, and Boyce index) and specificity (ability to predict absences), while the composite ENMs achieved higher sensitivity (ability to predict presences). In line with this, the composite ENMs also showed increased sensitivity and decreased specificity compared to the null models that randomised lineage structure. We showed that the assessment of model performance strongly varies based on the used measures, emphasising a careful investigation of multiple measures for evaluation. The application of null models allowed us to disentangle the effect of observed patterns of intraspecific variation in ENMs. Further, we highlight the validation and use of well‐founded subgroups for modelling. Although intraspecific variation improves the prediction of occurrences of European beech, it did not fully outcompete the classic species‐level model and should be used with care and rather to improve understanding and to supplement, not replace, species‐level models. [ABSTRACT FROM AUTHOR]

This evolutionary developmental study employed an experimental recursive narrative ecological niche, comparing scaffolded mother–child (5-year-old) pairs to unassisted controls as they independently viewed and discussed a realistic fictional family video depicting a father–daughter emotional conflict over the girl's risky behavior, which violated harm/care and fairness/justice moral foundation norms. A microgenetic analysis was conducted on a selected variant pair that demonstrated high adaptive fitness in the niche by employing developmentally advanced cooperative scaffolding tools. The conversational ecosystem phase was characterized by repeated maternal theory-oriented "why" questions and coordinated child causal responses, forming a joint epistemic investigation that facilitated the child's moral understanding of the characters' responsibilities and motives. The pair used quasi-justice procedures to gather evidence, judge, and construct moral attributes for the characters. Their conversational mechanism was supported by mutual mindreading, mental time travel, and empathic communications, as they interacted simultaneously with each other and the story characters. A narrative ecological scaffolding theory emerged, establishing a standard for cooperative epistemic scaffolding between the mother and the child. Future training programs should utilize the Zone of Proximal Development method to instruct similar parent–child pairs. [ABSTRACT FROM AUTHOR]

Magnetotactic bacteria (MTB) combine passive alignment with the Earth magnetic field with a chemotactic response (magneto-chemotaxis) to reach their optimal living depth in chemically stratified environments. Current magneto-aerotaxis models fail to explain the occurrence of MTB far below the oxic-anoxic interface and the coexistence of MTB cells with opposite magnetotactic polarity at depths that are unrelated with the redox gradient. Here we propose a modified model of polar magnetotaxis which explains these observations, as well as the distinct concentration profiles and magnetotactic advantages of two types of MTB inhabiting a freshwater sediment: a group of unidentified cocci (MC), and a giant rod-shaped bacterium (MB) apparently identical to M. bavaricum (MB). This model assumed that magnetotactic polarity is set by a threshold mechanism in counter gradients of oxygen and a second group of repellents, with, in case of MB, includes H+ ions. MTB possessing this type of polar magnetotaxis can shuttle between two limit depths across the redox gradient (redox taxis), as previously postulated for M. bavaricum and other members of the Nitrospirota group. The magnetotaxis of MB and MC is predominantly dipolar whenever the presence of a magnetic field ensures a magnetotactic advantage. In addition, MB can overcome unfavorable magnetic field configurations through a temporal sensing mechanism. The availability of threshold and temporal sensing mechanisms of different substances can generate a rich variety of responses by different types of MTB, enabling them to exploit multiple ecological niches. [ABSTRACT FROM AUTHOR]

There are 11 species of triatomines in the USA, with seven reported in the American Southwest. These species are capable of transmitting Trypanosoma cruzi, the etiological agent of Chagas disease, but are generally sylvatic and rarely infect humans in the USA. iNaturalist is one of the most popular citizen science data portals, where users record encounters with any individual organism. As of November 2023, iNaturalist reported 722 confirmed triatomine observations in the American Southwest. Maximum entropy ecological niche modelling and bioclimatic environmental variables were used to predict zones of highest human-triatomine interaction. Models fit well for Triatoma protracta (0.85), T. rubida (0.94), and T. recurva (0.96). Precipitation in the warmest quarter was most predictive of T. protracta presence, while precipitation in the driest quarter was most predictive of T. rubida and T. recurva. Locations identified in the American Southwest with highest potential for human-triatomine interaction, and potential T. cruzi transmission, were coastal California, the Sierra Nevada foothills, southern Arizona and border areas of northern Mexico. Study findings can be used for targeted surveillance efforts to address the paucity of contemporary information regarding triatomine species diversity and geographical and ecological associations in the American Southwest. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are invaluable for delineating ecological niches and assessing habitat suitability, facilitating the projection of species distributions across spatial and temporal dimensions. This capability is crucial for conservation planning, habitat management and understanding the impacts of climate change. Remote sensing has emerged as a superior alternative to traditional field surveys in developing SDMs, offering cost-effective, repetitive data collection over comprehensive spatial and temporal scales. Despite the rapid advancements in remote sensing technologies and analytical methods, the specific contributions of remote sensing to SDMs historically, and the potential pathways for its integration with SDMs remain ambiguous. Therefore, our study has set forth two objectives: firstly, to conduct a thorough review of remote sensing’s role in SDMs, focusing on environmental predictors, response variables, scalability and validation; secondly, to outline prospective research trajectories for remote sensing within SDMs. Our findings reveal that remote sensing offers a plethora of environmental predictors for SDMs, encompassing climate, topography, land cover and use, spectral metrics and biogeochemical cycles. A variety of remote sensing techniques, including random forest, deep learning and linear unmixing, facilitate the derivation of SDM response variables and the development of species distribution models across diverse scales. Furthermore, remote sensing enables the validation of SDMs through its mapping outputs. [ABSTRACT FROM AUTHOR]

This study examines the population structure, ecological niche, and vulnerability to climate change of the woolly dormouse Dryomys laniger in Türkiye. Integrating genetic data with species distribution modeling, the research predicts suitable habitats for D. laniger under current and future climate change scenarios until the year 2100. Using an ensemble of two machine learning models, this study finds that by 2040, the range of D. laniger will be reduced significantly, particularly in southern populations. Eastern areas emerge as a potential refuge, showing slight expansion and colonization. The low genetic diversity in this eastern population indicates the need for long-term adaptability of D. laniger. Due to the unique adaptive potential of each population, this research highlights the importance of region-specific management plans to ensure the long-term survival of this species, which appears to be vulnerable to habitat fragmentation. [ABSTRACT FROM AUTHOR]

Many phytopathogens' gene products that contribute to plant–pathogen interactions remain unexplored. In one of the most harmful phytopathogenic bacterium Pectobacterium atrosepticum (Pba), phosphonate-related genes have been previously shown to be among the most upregulated following host plant colonization. However, phosphonates, compounds characterized by a carbon–phosphorus bond in their composition, have not been described in Pectobacterium species and other phytopathogenic bacteria, with the exception of Pseudomonas syringae and Pantoea ananatis. Our study aimed to determine whether Pba synthesizes extracellular phosphonates and, if so, to analyze their physiological functions. We demonstrated that Pba produces two types of extracellular phosphonates: 2-diethoxyphosphorylethanamine and phenylphosphonic acid. Notably, such structures have not been previously described among natural phosphonates. The production of Pba phosphonates was shown to be positively regulated by quorum sensing and in the presence of pectic compounds. Pba phosphonates were found to have a positive effect on Pba stress resistance and a negative effect on Pba virulence. The discovered Pba phosphonates are discussed as metabolites that enable Pba to control its "harmful properties", thereby maintaining its ecological niche (the host plant) in a relatively functional state for an extended period. [ABSTRACT FROM AUTHOR]

Niche segregation is a mechanism by which competition between coexisting species is reduced. The ecological niche is a multidimensional space shaped by the conditions and resources that enable the existence of species.We conducted comprehensive univariate and multidimensional analyses of phenotypic traits encompassing morphology, functional performance and ecophysiology, to investigate which phenotypic traits contribute to niche segregation and overlap in two coexisting green lizard species.Our analyses revealed that the main driver of niche segregation was body size. However, when considering size‐corrected phenotypic spaces, ecophysiological traits were still distinct, with little overlap between co‐occurring species. Such differentiation was linked mainly to preferred temperature variance and water loss, highlighting the importance of thermal and hydric niche segregation.Some particular traits such as limb length also contributed to niche segregation being maintained in the morphological space, even when the effect of size was accounted for. Instead, the phenotypic space of functional performance traits (i.e. bite force, locomotor performance) showed the greatest overlap between the two species, thus, less niche segregation was observed, once size effects were removed. Therefore, functional performance traits contribute in a minor proportion to the effective niche segregation between the two species. In light of our results, the most adequate perspective to understand niche segregation in coexisting species is through a multidimensional approach in differentiated phenotypic spaces. Our dismantling of phenotypic traits allowed us to identify niche areas in which trait overlap occurs and others that promote niche segregation, considering or not size effects.Our results suggest that differential use of structural and functional niche space promotes effective niche segregation, potentially reducing direct competition between species. We highlight the importance of studies that include the combination of several phenotypic traits that, as a whole, provide insights to better understand the mechanisms by which coexisting organisms exploit differentiated resources in multidimensional spaces. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The article discusses the thermal adaptation strategies of desert locusts in the Sahara Desert, focusing on mate-guarding behavior that helps ovipositing females avoid overheating in extremely hot conditions. Male locusts act as parasols for females by mounting them during daytime oviposition, reducing their body temperatures significantly. This mate-guarding behavior may serve as a defensive strategy to cool females and expand their ecological niches. The study suggests that understanding these thermoregulatory strategies could aid in environmentally conscious pest control and help desert locusts adapt to future climate change. [Extracted from the article]

By 1985, approximately 400,000 ha of the keystone species Shinnery oak's (Quercus havardii) historic distribution had been eliminated for agricultural purposes across the southwestern United States. These trends indicate a need for targeted conservation and restoration efforts, especially considering the increased attention received for its role in providing habitat for endangered fauna. Setting spatially explicit conservation targets can be challenging for species with limited distributions, as the change in climate conditions over time may disconnect the relationship between environmental suitability and static, topo‐edaphic factors. Our objective was to identify areas for Shinnery oak restoration and conservation and explore the role climate plays in determining these areas while considering topo‐edaphic relationships. We constructed ecological niche models to estimate Shinnery oak's distribution under current climate conditions and temporally transferred our model using an ensemble‐mean of general circulation models to identify areas predicted to retain environmental suitability for Shinnery oak through 2100. The current distribution model was best informed by one climate and two topo‐edaphic variables. We created a second distribution model excluding topo‐edaphic variables to estimate future plant–climate relationships. Incorporating insights from models informed by both static (e.g. soil) and dynamic (e.g. climate) variables, we identified areas for conservation characterized by persistent climate suitability and high soil type suitability. Lastly, we incorporated data on land use and ownership to explore socio‐ecological influences on management decisions. By identifying areas of agreement between our modeled distributions and considering social context, we prioritized conservation areas where environmental suitability persists under changing conditions to facilitate restoration success. [ABSTRACT FROM AUTHOR]

Ecological niche differentiation is a process that accompanies lineage diversification and community assembly. Traditionally, the degree of niche differentiation is estimated by contrasting niche hypervolumes of two taxa, reconstructed using ecologically relevant variables. These methods disregard the fact that niches can shift in different ways and directions. Without means of discriminating between different types of niche differentiation, important evolutionary and ecological patterns may go unrecognized. Herein, we introduce a new conceptual and methodological framework that allows quantification and classification of niche differentiation and divergence between taxa along single niche axis. This new method, the Niche Divergence Plane, is based on species' responses to an underlying environmental gradient, from which we derive a two‐dimensional plane defined by two indices, niche exclusivity and niche dissimilarity. These two indices identify the proportion of the environmental gradient that is unique to each species, that is, how much of the environmental gradient species do not share (niche breadth exclusivity) and how different the species' responses are along the environmental gradient (niche dissimilarity). Thus, the latter can also be seen as a measure of the differences in niche preference or importance, even when there is significant overlap in niche breadth (i.e., low niche exclusivity). Based on the position of the two indices on the divergence plane, we can distinguish niche conservatism from four other general types of niche divergence: hard, soft, weighted, and nested. We demonstrate that the Niche Divergence Plane complements traditional measures of niche similarity (e.g., Schoener's D or Hellinger's I). Additionally, we show an empirical comparison using the Niche Divergence Plane framework on two Ambystoma salamanders. Overall, we demonstrate that the Niche Divergence Plane is a versatile tool that can be used to complement and expand previous methods of ecological niche comparisons and the study of ecological niche divergence. [ABSTRACT FROM AUTHOR]

The widespread bacterial genus Sulfurimonas is metabolically versatile and occupies a key ecological niche in different habitats, but its interaction with bacteriophages remains unexplored. Here we systematically investigated the genetic diversity, taxonomy and interaction patterns of Sulfurimonas-associated phages based on sequenced microbial genomes and metagenomes. High-confidence phage contigs related to Sulfurimonas were retrieved from various ecosystems, clustered into 61 viral operational taxonomic units across three viral realms, including Duplodnaviria, Monodnaviria and Varidnaviria. Head-tail phages of Caudoviricetes were assigned to 19 genus-level viral clusters, the majority of which were distantly related to known viruses. Notably, diverse double jelly-roll viruses and inoviruses were also linked to Sulfurimonas, representing two commonly overlooked phage groups. Historical and current phage infections were revealed, implying viral impact on the evolution of host adaptive immunity. Additionally, phages carrying auxiliary metabolic genes might benefit hosts by compensating or augmenting sulfur metabolism. This study highlights the diversity and novelty of Sulfurimonas-associated phages with divergent tailless lineages, providing basis for further investigation of phage-host interactions within this genus. A catalog of phages associated with Sulfurimonas reveals unexplored diversity and potential viral impacts, providing new insight into the phage-host coevolution. [ABSTRACT FROM AUTHOR]

Studies have found that biotic information can play an important role in shaping the distribution of species even at large scales. However, results from species distribution models are not always consistent among studies and the underlying factors that influence the importance of biotic information to distribution models, are unclear. We studied wild bees and plants, and cleptoparasite bees and their hosts in the Netherlands to evaluate how the inclusion of their biotic interactions affects the performance of species distribution models. We assessed model performance through spatial block cross‐validation and by comparing models with interactions to models where the interacting species was randomized. Finally, we evaluated how, 1) spatial resolution, 2) taxonomic rank (genus or species), 3) degree of specialization, 4) distribution of the biotic factor, 5) bee body size and 6) type of biotic interaction, affect the importance of biotic interactions in shaping the distribution of wild bee species using generalized linear models (GLMs). We found that the models of wild bees improved when the biotic factor was included. The model performance improved the most for parasitic bees. Spatial resolution, taxonomic rank, distribution range of the biotic factor and degree of specialization of the modelled species all influenced the importance of the biotic interaction to the models. We encourage researchers to include biotic interactions in species distribution models, especially for specialized species and when the biotic factor has a limited distribution range. However, before adding the biotic factor we suggest considering different spatial resolutions and taxonomic ranks of the biotic factor. We recommend using single species or genus data as a biotic factor in the models of specialist species and for the generalist species, we recommend using an approximate measure of interactions, such as flower richness. [ABSTRACT FROM AUTHOR]

ABSTRACT Vulnerable marine ecosystems (VMEs) are typically fragile and slow to recover, thereby making them susceptible to disturbance, including fishing. In the high seas, the United Nations General Assembly (UNGA) requested regional fishery management organisations (RFMOs) to implement measures to prevent significant adverse impacts on VMEs. Here, we predict spatial abundances of 15 taxa, 13 VME indicator taxa, in the South Pacific RFMO (SPRFMO) area. Models used seafloor imagery data, an important advance on previously developed presence‐only predictions, to provide information on spatial variation in taxa abundance that is crucial for better inferring likely location of VMEs, rather than just distribution of VME indicator taxa. Abundance models varied in predictive power (mean R2 ranged 0.02–0.40). Uncertainty estimates of model predictions were developed to inform future spatial planning processes for conservation and management of VMEs. Using the VME index concept, abundance model outputs and previously published presence‐only model predictions were weighted using vulnerability scores, to explore how modelled outputs could provide spatial estimates of likely VME distribution. Spatial predictions of abundance improved on previous modelling to provide an almost complete suite of abundance models for VME indicator taxa in the western portion of the SPRFMO Convention area. Nevertheless, to improve utility of modelled outputs, we recommend more high‐quality seafloor imagery data be gathered within the SPRFMO Convention area to (1) validate abundance models developed here with independent data from the model area, (2) update models, if necessary, (3) link abundance information to ecosystem function and (4) explore validity of the adapted VME index approach used here. [ABSTRACT FROM AUTHOR]

Previous studies have emphasised the positive role of digital technologies in gaining competitive advantage, but the differences between technologies and the role of environmental matching have been overlooked. In this paper, we explore the relative positions and competitive landscape formed by digital technology firms. First, the study uses an NLP approach to measure corporate ecological niche based on digital business, which includes two indicators of width and overlap, and the original corpus comes from the annual reports of 409 listed companies. Then, based on the ecological niche separation theory, we analyse the competitive effects. The results show that the competitive effect formed by the representative digital technology enterprises can be divided into complementary, independent and substitution. Among them, cloud computing and big data enterprises are at the stage of complementary effect, blockchain enterprises form a unique independent competitive pattern, while the substitution effect of artificial intelligence and Internet of Things enterprises is more obvious. This paper implements an ecological niche measure that embodies digital features, which delivers fresh and useful insights into the application of the ecological niche theory in the digital environments and further reveals the unique competitive dynamics in the digital environment. [ABSTRACT FROM AUTHOR]

Aim: To provide an assessment of climate change impacts on a set of wild pollinators restricted to one of the regions with the greatest diversity of bees in the world. Also, we aimed to test whether functional groups responded differently to climate projections. Location: South‐eastern South America (SES). Taxon: Bees (Hymenoptera: Apidae sensu lato). Methods: We selected 18 species of bees mostly restricted to the SES region, modelled their distributions and assessed the possible impacts of near future (2050) climate change in species richness and shifts in range centroids. Potential impacts related to different functional groups were evaluated through t‐tests. Results: SES species richness was projected to decrease in the northernmost regions and increase southward. Most bee species were predicted to shift their range centroids towards the south‐west and south, while suitable stable areas were found in southern Brazil. We also found higher proportional losses in suitable areas for eusocial species compared to solitary ones, while generalists showed slightly lower gains than specialists. Main Conclusion: SES bees are likely to undergo changes in the near future, with projected losses of species at northern portions and southward increases. The identified stable areas in southern Brazil underscore the importance of conservation efforts in the region, particularly in natural grasslands – an endangered habitat with high bee diversity. Although our results suggest higher vulnerability for functional groups traditionally considered more resilient, it is essential to acknowledge that other factors, including habitat and mutualists availability, behavioural particularities, phenology and range size, must be determinants for the vulnerability of species to ongoing climate change. [ABSTRACT FROM AUTHOR]

Aim: To date a vicariant event through the mutualistic relationship of a hylid frog and its bromeliad host found across two isolated mountain ranges as part of an island–continental split and to use this information to calibrate a molecular dating analysis of hylids. Location: South America. Time Period: Pliocene. Major Taxa Studied: Treefrogs, Arboranae. Methods: Pliocene tectonic movements sank a portion of a mountain range that connected present‐day Trinidad (island) and northern Venezuela, eventually isolating populations of the golden tree frog Phytotriades auratus and its host bromeliad Glomeropitcairnia erectiflora on both sides of a saltwater barrier. We estimated the submersion rate timing of the vicariant event, then employed ecological niche modelling to establish the distribution of the frog and its host to the Pliocene. We generated nucleotide sequence data for the hylid on each side of the marine barrier and proposed a biogeographic calibration for the split between populations. Using Bayesian phylogenetic analysis, we evaluated the impact of incorporating this biogeographic calibration on estimates of treefrog divergence times. Results: A relatively continuous, high‐elevation mountain range existed before the Pliocene and the opening of the Gulf of Paria (4.45 ± 0.85 Ma). Phytotriades auratus and G. erectiflora would have been distributed across the Paria and Northern Range mountains as a single population since the Pliocene. Divergence times among treefrogs (Arboranae) were older than those inferred using fossil calibrations alone, with mean age estimates for subfamilies and genera being ~2 and ~1.2 million years older, respectively. Main Conclusions: Our study presents a biogeographic calibration based on a vicariant model that connects the evolution of the populations of a hylid through geology and ecological data. The implementation of this date as a molecular clock calibration reduces the uncertainty in date estimates for the shallower nodes in the phylogeny of Arboranae. [ABSTRACT FROM AUTHOR]

Aegerolysin proteins are involved in various interactions by recognising a molecular receptor in the target organism. The formation of pores in combination with larger, non‐aegerolysin‐like protein partners (such as membrane attack complex/perforin proteins [MACPFs]) is one of the possible responses in the presumed competitive exclusion of other organisms from the ecological niche. Bicomponent pairs are already observed at the gene level. Fungi growing under extreme conditions can be divided into ubiquitous and extremotolerant generalists which can compete with mesophilic species and rare, isolated extremophilic and extremotolerant specialists with narrow ecological amplitude that cannot compete. Under extreme conditions, there are fewer competitors, so fungal specialists generally produce less diverse and complicated profiles of specialised molecules. Since extremotolerant and extremophilic fungi have evolved in numerous branches of the fungal tree of life and aegerolysins are unevenly distributed across fungal genomes, we investigated whether aegerolysins, together with their partner proteins, contribute to the extreme survival ecology of generalists and specialists. We compiled a list of 109 thermo‐, psihro‐, acido‐, alkali‐, halo‐, metallo‐ and polyextremo‐tolerant/‐philic fungal species. Several challenges were identified that affected the outcome: renaming fungal species, defining extremotolerant/extremophilic traits, identifying extremotolerant/extremophilic traits as metadata in databases and linking fungal isolates to fungal genomes. The yield of genomes coding aegerolysins or MACPFs appears to be lower in extremotolerant/extremophilic fungi compared to all fungal genomes. No candidates for pore‐forming gene pairs were identified in the genomes of extremophilic fungi. Aegerolysin and MACPFs partner pairs were identified in only two of 69 species with sequenced genomes, namely in the ubiquitous metallotolerant generalists Aspergillus niger and A. foetidus. These results support the hypothesised role of these pore‐forming proteins in competitive exclusion. [ABSTRACT FROM AUTHOR]

Cliff ecology has been studied for decades, providing information about its high biodiversity values and their vulnerability to climate change. Also, insular ecosystems present biodiversity hotspots with high endemicity, but they are also severely affected by anthropogenic effects. Together, insular cliff communities combine both biodiversity uniqueness and high vulnerability to global change, but few studies have evaluated these particular ecosystems. Our aim was to provide information on the spatial distribution of insular cliff-specific vegetation assessing which environmental and climatic variables contribute to the definition of cliff habitat conditions. Ecological niche modelling for cliff populations in Balearic Islands has been calculated with presences of 20 plant species and climatic and geographical variables using a Random Forest model. The most important climatic variables for the model generation were mean temperature of the driest quarter and precipitation of the coldest quarter. The map obtained showed that mountain ranges from all islands provide highly suitable conditions for rupicolous species. Both the pessimistic and optimistic models showed that the habitat suitability of cliff vegetation in the mountain ranges would decrease, while they are close to zero in lowlands for the period 2021–2040. This study emphasizes the vulnerability of cliff habitats to climate change due to their limited dispersal capacity and distribution and the strict requirements for habitat suitability. From this work, future studies can focus on single-species analysis to evaluate if any cliff specialist species can be at risk of extinction due to climate change. [ABSTRACT FROM AUTHOR]

Blastomycosis is a disease of potentially varied presentations caused by thermally dimorphic fungi that appear as mold at ambient temperatures and transform to yeast at body temperature. Inhalation of aerosolized fungal spores represents the primary mode of transmission. Exposure may follow outdoor activities that disturb soil, which is warm, moist, acidic and rich in organic debris, particularly within forested areas and in proximity to waterways. Blastomycosis is endemic to several parts of Canada, but is only reportable in Ontario and Manitoba, with Northwestern Ontario being considered a hyperendemic area with average annual incidence rates of over 25 cases per 100,000 population. Delays in diagnosis and treatment are frequently observed as the symptoms and imaging findings of blastomycosis may initially be mistaken for community-acquired pneumonia, tuberculosis or malignancy, which can result in interim disease progression and worsening clinical outcomes. Risks from fungal infections such as blastomycosis are likely to increase with climate change-associated shifts in temperature and rainfall, and this may contribute to the geographic expansion of cases, a phenomenon that appears to be already underway. Further research investigating the ecological niche of Blastomyces and its climate sensitivity could help facilitate better modelling of the potential impacts of climate change on risks to Canadians and inform more effective methods of exposure prevention. Early clinical recognition and treatment of blastomycosis remain the key to minimizing morbidity and mortality. [ABSTRACT FROM AUTHOR]

Introduction: Plants are inherently connected with the microbiome, which plays a crucial role in regulating various host plant biological processes, including immunity, nutrient acquisition, and resistance against abiotic and biotic stresses. Many factors affect the interaction between plants and microbiome. Methods and results: In this study, microbiome samples were collected from five niches (bulk soil, rhizoplane, root endosphere, phylloplane, and leaf endosphere) across four developmental stages (seedling, flowering, podding, and maturity) of various soybean varieties. Composition and structure of bacterial and fungal communities were analyzed using 16S rRNA gene and ITS (Internally Transcribed Spacer) region amplicon sequencing. It was observed that both niches and developmental stages significantly impact on the assembly and composition of soybean microbiome. However, variety, presence of a transgene, and glyphosate application had minimal effects on microbial communities. The dominant microbiome varied across the five niches, with most containing beneficial microbial communities capable of promoting plant growth or increasing disease resistance. Types and abundance of the dominant microbes affected network stability, potentially resulting in functional changes in different ecological niches. Conclusion: This study provides theoretical evidence for microbial protection of plants against diseases and demonstrates that systematic analysis of the composition and diversity of soybean microbiomes can contribute to the development of biological control technologies. [ABSTRACT FROM AUTHOR]

The intrusion of the Pearl River plume into the Taiwan Strait provides a unique case study that challenges traditional assumptions about the impacts of nutrient-rich river plumes on coastal phytoplankton communities. In this study, we conducted a detailed analysis of nutrient dynamics and phytoplankton composition within the Taiwan Strait, focusing on the effects of the Pearl River plume. Our findings reveal significant nutrient depletion, particularly of nitrogen, in the surface waters as the plume extends seaward, resulting in nitrogen limitation and a marked reduction in phytoplankton biomass. Vertical stratification within the Taiwan Strait creates distinct ecological niches, with the mid-layer supporting a deep chlorophyll maximum and the surface layer becoming dominated by the picophytoplankton Synechococcus. This shift from diatom-dominated communities to Synechococcus dominance has far-reaching implications for carbon cycling and food web dynamics in the region. Our results suggest that the Pearl River plume's influence on the Taiwan Strait represents a departure from the typical nutrient enrichment associated with river plumes, highlighting the complexity of coastal biogeochemical processes. [ABSTRACT FROM AUTHOR]

Marine plastic pollution poses a growing environmental threat, with microplastics accumulating in the global oceans. This study profiles the seasonal dynamics and taxonomic composition of the plastisphere, the microplastic ecosystem, in the Eastern Mediterranean Sea. Using long-read 16 S and 18 S metabarcoding, we analyzed offshore microplastic and whole seawater samples across each season over a two-year period. The analysis revealed a higher richness of prokaryotic communities on microplastics compared to seawater, which was predominantly composed of Proteobacteria and Bacteroidota and exhibited notable seasonal variability. Benthic eukaryotes were enriched on microplastics compared to the surrounding seawater. Diatoms (Bacillariophyceae), in particular, showed significant enrichment within the microplastic eukaryotic community with primarily pennate diatoms of Amphora, Navicula, and Nitzschia genera, whereas the seawater included mostly centric diatoms. Seasonal fluctuations were less pronounced in the microplastic communities than in seawater, highlighting the relative stability of this new human-made ecosystem. These findings underscore the unique ecological niche of microplastic-associated communities in marine environments. [ABSTRACT FROM AUTHOR]

The soybean pod borer, Leguminivora glycinivorella (Matsumura), is an important tortricid pest species widely distributed in most parts of China and its adjacent regions. Here, we analyzed the genetic diversity and population differentiation of L. glycinivorella using diverse genetic information including the standard cox1 barcode sequences, mitochondrial genomes (mitogenomes), and single‐nucleotide polymorphisms (SNPs) from genotyping‐by‐sequencing. Based on a comprehensive sampling (including adults or larvae of L. glycinivorella newly collected at 22 of the total 30 localities examined) that covers most of the known distribution range of this pest, analyses of 543 cox1 barcode sequences and 60 mitogenomes revealed that the traditionally recognized and widely distributed L. glycinivorella contains two sympatric and widely distributed genetic lineages (A and B) that were estimated to have diverged ∼1.14 million years ago during the middle Pleistocene. Moreover, low but statistically significant correlations were recognized between genetic differentiation and geographic or environmental distances, indicating the existence of local adaptation to some extent. Based on SNPs, phylogenetic inference, principal component analysis, fixation index, and admixture analysis all confirm the two divergent sympatric lineages. Compared with the stable demographic history of Lineage B, the expansion of Lineage A had possibly made the secondary contact of the two lineages probable, and this process may be driven by the climate fluctuation during the late Pleistocene as revealed by ecological niche modeling. [ABSTRACT FROM AUTHOR]

Background: In China, decline disease with unknown etiology appeared as an epidemic among bayberry trees in the southern area of the Yangtze River. Furthermore, the use of beneficial microbes has been reported to be able to reduce the incidence of this disease, emphasizing the association of this disease with microorganisms. Therefore, it has become critical to uncover the microbiome's function and related metabolites in remodeling the immunity of bayberry trees under biotic or abiotic stresses. Results: The amplicon sequencing data revealed that decline disease significantly altered bacterial and fungal communities, and their metabolites in the four distinct niches, especially in the rhizosphere soils and roots. Furthermore, the microbial communities in the four niches correlated with the metabolites of the corresponding niches of bayberry plants, and the fungal and bacterial networks of healthy trees were shown to be more complex than those of diseased trees. In addition, the role of microbiome in the resistance of bayberry trees to the occurrence of decline disease was justified by the isolation, identification, and characterization of important microorganisms such as significantly enriched Bacillus ASV804, Pseudomonas ASV815 in healthy plants, and significantly enriched Stenotrophomonas ASV719 in diseased plants. Conclusion: Overall, our study revealed that the occurrence of decline disease altered the microbiome and its metabolites in four ecological niches in particular rhizosphere soils and roots of bayberry, which provides new insight into the control of bayberry decline disease. [ABSTRACT FROM AUTHOR]

Background: The snake genera Atropoides, Cerrophidion, and Metlapilcoatlus form a clade of neotropical pit vipers distributed across Mexico and Central America. This study evaluated the myotoxic and neurotoxic effects of nine species of Atropoides, Cerrophidion, and Metlapilcoatlus, and the neutralising efficacy of the ICP antivenom from Costa Rica against these effects, in the chick biventer cervicis nerve-muscle preparation. Given the prominence of PLA2s within the venom proteomes of these species, we also aimed to determine the neutralising potency of the PLA2 inhibitor, varespladib. Results: All venoms showed myotoxic and potential neurotoxic effects, with differential intra-genera and inter-genera potency. This variation was also seen in the antivenom ability to neutralise the muscle damaging pathophysiological effects observed. Variation was also seen in the relative response to the PLA2 inhibitor varespladib. While the myotoxic effects of M. mexicanus and M. nummifer venoms were effectively neutralised by varespladib, indicating myotoxicity is PLA2 mediated, those of C. godmani and M. olmec venoms were not, revealing that the myotoxicity is driven by non-PLA2 toxin types. Conclusions: This study characterises the myotoxic and neurotoxic venom activity, as well as neutralisation of venom effects from the Atropoides, Cerrophidion, and Metlapilcoatlus clade of American crotalids. Our findings contribute significant clinical and evolutionary knowledge to a clade of poorly researched snakes. In addition, these results provide a platform for future research into the reciprocal interaction between ecological niche specialisation and venom evolution, as well as highlighting the need to test purified toxins to accurately evaluate the potential effects observed in these venoms. [ABSTRACT FROM AUTHOR]

Recent phylogenetic analyses of anchored‐hybrid, transcriptomic and morphological data have consistently recovered a clade comprising the three previously recognized families of treehoppers (Hemiptera), Aetalionidae, Melizoderidae and Membracidae, as well as two groups traditionally included in the leafhopper family Cicadellidae as subfamilies Megophthalminae and Ulopinae. To reconstruct the phylogeny of these two groups of treehopper‐like leafhoppers, maximum likelihood and multi‐species coalescent analyses were performed on a molecular DNA dataset consisting of ~700 anchored hybrid loci representing 84 terminal taxa. Analyses based on different dataset subsets and approaches yielded largely congruent topologies, although the relationships among Megophthalminae, Ulopinae and treehoppers are still unstable. The monophyly of both subfamilies is strongly supported, but several tribes, including Agalliini, Cephalelini, Megophthalmini and Ulopini, are recovered as non‐monophyletic. The origin of Megophthalminae and Ulopinae was estimated as early Cretaceous (~140 million years ago), and the divergence within each subfamily began in the mid‐Cretaceous. Continental‐scale biogeographic structure is evident in these two groups, with genera occurring on the same continent tending to group together regardless of tribal placement, suggesting that extensive morphological convergence occurred among faunas inhabiting different regions. Ancestral microhabitat reconstruction suggested that megophthalmine and ulopine leafhoppers originally lived on trees or shrubs and later several groups evolved independently to inhabit leaf litter and soil. Convergent modifications of the ocelli, forewings and hindwings accompanied changes in microhabitat preference. [ABSTRACT FROM AUTHOR]

ABSTRACT Studying niche evolution becomes central to understanding the processes driving species diversification along latitudinal gradients. Octodontoidea rodents serve as a model group for understanding how the colonisation of extratropical regions has shaped the climatic niche evolution of species. We analyse the time and mode of climatic niche evolution among different Octodontoidea lineages to understand how niche evolutionary processes operate across the spatial gradient of the Neotropical region. We constructed ecological niche models for living Octodontoidea species to assess the timing and mode of climatic niche evolution across tropical and extratropical lineages. We estimated niche similarity and correlated it with species divergence times, and estimated the rate of climatic niche diversification across lineages. Our results show a trend of greater niche overlap in more recent lineages and lower niche overlap in older lineages. However, extratropical lineages exhibit lower climatic niche overlaps. From diversification analysis, we detected that the Ctenomyidae group shows higher rates of niche diversification, whereas the tropical Echimyidae group exhibits the lowest rates of climatic niche diversification. Our results support the idea that the lineages restricted to tropical regions tend towards niche conservatism. However, some tropical lineages have successfully colonised extratropical regions, and this colonisation has been accompanied by strong selective pressures, leading to higher rates of niche diversification and lower climatic niche overlap among species. [ABSTRACT FROM AUTHOR]

Electroreception is the capacity of living organisms to detect the presence of electricity, usually studied in the aquatic environment. Electroreception in air, however, has received much less attention until relatively recently. Understanding how and why aerial electroreception may work requires a multidisciplinary framework, anchored in both the physics of static electricity and the ecology of sensory biology. In essence, the novel challenge arises from the fact that air is a much less conductive medium than water. Yet, recent research on terrestrial arthropods, including bees, flies, spiders, worms and caterpillars, has unveiled sensitivity to electric fields in different sensory ecological contexts. For each aerial organism considered thus far, filiform hairs and/or the antennae have been proposed to be the specialised sensory structures enabling detection based on both empirical and theoretical evidence. This newfound sensory modality reveals a previously unrecognised source of information, a new informational ecological niche integral to diverse life histories and navigational abilities, which remarkably involves animals, plants and atmospheric electricity (Figure 1). Understanding aerial electroreception in arthropods opens avenues for exploring their behaviour and ecology in diverse environments and sheds light on the evolution of sensory adaptations in terrestrial organisms. Because, as is known today, humans are not sensitive to weak electric fields, challenges arise in our comprehension of the elusive and discrete nature of aerial electric fields, and how they could be detected and used by terrestrial organisms. Daniel Robert introduces aerial electroreception, a sensory modality documented in terrestrial arthropods, such as bees and spiders, that is based on electrostatic charging, and operates in the contexts of plant–pollinator and predator–prey interactions, as well as in dispersal and phoretic behaviours. [ABSTRACT FROM AUTHOR]

The bioavailable nitrogen fixed by diazotrophs is critical for sustaining productivity in the oligotrophic ocean. Despite this, understanding how diazotroph-derived nitrogen integrates into the nitrogen cycle within the euphotic zone remains unknown. Here, we investigated nitrogen fixation rates in the particulate and dissolved fractions within the euphotic zone of the North Pacific Subtropical Gyre. Our findings reveal the proportion of nitrogen fixation rates in the dissolved fraction increases with depth. Light manipulation experiments uncover that reduced light levels can stimulate the net release of diazotroph-derived nitrogen, aligning with our depth-related observations. Furthermore, we identify two distinct transfer pathways vertically associated with light-driven ecological niches. Specifically, the released diazotroph-derived nitrogen is transferred to non-diazotrophic plankton in the upper layers. Meanwhile, in the lower layers, it contributes to the nitrification process. Our results underscore the high bioavailability of diazotroph-derived nitrogen and its rapid integration into the nitrogen cycle through multiple pathways within the well-lit ocean. New study finds diazotroph-derived nitrogen is utilized by phytoplankton in upper euphotic zone, while below, it is used by nitrifiers. The newly identified pathways reveal the marine nitrogen cycle may be more interconnected than previously recognized. [ABSTRACT FROM AUTHOR]

Throughout the world, the exceptional biodiversity and endemism of spring ecosystems are threatened by the expansion of invasive species. However, mechanisms affecting the distribution and impact of invasive species on spring macroinvertebrate communities remain poorly understood. We investigated the impact of the invasive New Zealand mud snail Potamopyrgus antipodarum on the native gastropod assemblages of 43 karstic springs in Bosnia and Herzegovina. Firstly, we showed that P. antipodarum invaded only human‐modified low‐altitude springs with lower dissolved oxygen concentrations (7.61 mg/L), where it co‐occurred only with four other gastropod species (out of the 17 recorded in our dataset), two of which are endemic Dinaric karst spring specialists. Then, by comparing the n‐dimensional ecological space of the springs invaded and uninvaded by the mud snail, we showed that low‐altitude springs have a higher risk of invasion. Finally, we characterized the shift in the niche optimum exhibited by native endemic gastropods in invaded springs using Huisman–Olff–Fresco models. Overall, we showed that human alterations of low‐altitude springs might facilitate the invasion of P. antipodarum, which possibly out‐competes endemic crenic species by displacing them to suboptimal niches. The use of Huisman–Olff–Fresco models and n‐dimensional hypervolumes together provided a useful framework for quantifying the response of endemic and endangered species to the spread of invaders in globally endangered spring habitats. [ABSTRACT FROM AUTHOR]

Theropithecus gelada, the last surviving species of this genus, occupy a unique and highly specialised ecological niche in the Ethiopian highlands. A subdivision into three geographically defined populations (Northern, Central and Southern) has been tentatively proposed for this species on the basis of genetic analyses, but genomic data have been investigated only for two of these groups (Northern and Central). Here we combined newly generated whole genome sequences of individuals sampled from the population living south of the East Africa Great Rift Valley with available data from the other two gelada populations to reconstruct the evolutionary history of the species. Integrating genomic and paleoclimatic data we found that gene‐flow across populations and with Papio species tracked past climate changes. The isolation and climatic conditions experienced by Southern geladas during the Holocene shaped local diversity and generated diet‐related genomic signatures. [ABSTRACT FROM AUTHOR]

Coral microbiomes play crucial roles in holobiont homeostasis and adaptation. The host's ability to populate broad ecological niches and to cope with environmental changes seems to be related to the flexibility of the coral microbiome. By means of high-throughput DNA sequencing we characterized simultaneously both bacterial (16S rRNA) and Symbiodiniaceae (ITS2) communities of four reef-building coral species (Mussismilia braziliensis, Mussismilia harttii, Montastraea cavernosa, and Favia gravida) that differ in geographic distribution and niche specificity. Samples were collected in a marginal reef system (Abrolhos, Brazil) in four sites of contrasting irradiance and turbidity. Biological filters governed by the host are important in shaping corals' microbiome structure. More structured associated microbial communities by reef site tend to occur in coral species with broader geographic and depth ranges, especially for Symbiodiniaceae, whereas the endemic and habitat-specialist host, M. braziliensis, has relatively more homogenous bacterial communities with more exclusive members. Our findings lend credence to the hypothesis that higher microbiome flexibility renders corals more adaptable to diverse environments, a trend that should be investigated in more hosts and reef areas. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) underpin a wide range of decisions concerning biodiversity. Although SDMs can be built using presence‐only data, rigorous evaluation of these models remains challenging. One evaluation method is the Boyce index (BI), which uses the relative frequencies between presence sites and background sites within a series of bins or moving windows spanning the entire range of predicted values from the SDM. Obtaining accurate estimates of the BI using these methods relies upon having a large number of presences, which is often not feasible, particularly for rare or restricted species that are often the focus of modelling. Wider application of the BI requires a method that can accurately and reliably estimate the BI using small numbers of presence records. In this study, we investigated the effectiveness of five statistical smoothing methods (i.e. thin plate regression splines, cubic regression splines, B‐splines, P‐splines and adaptive smoothers) and the mean of these five methods (denoted as ‘mean') to estimate the BI. We simulated 600 species with varying prevalence and built distribution models using random forest and Maxent methods. For training data, we used two levels for the number of presences (NPtrain: 20 and 500), along with 2 × NPtrain and 10000 random points (i.e. random background sites) for each modelling method. We used the number of presences at four levels (NPbi: 1000, 200, 50 and 10) to investigate its effect, together with 5000 random points to calculate the BI. Our results indicate that the BI estimates from the binning and moving window methods are severely affected by the decrease of NPbi, but all the estimates of the BI from smoothing‐based methods were almost always unbiased for realistic situations. Hence, we recommend these methods for estimating the BI for evaluating SDMs when verified absence data are unavailable. [ABSTRACT FROM AUTHOR]

Over the past 3 million years, humans have expanded their ecological niche and adapted to more diverse environments. The temporal evolution and underlying drivers behind this niche expansion remain largely unknown. By combining archeological findings with landscape topographic data and model simulations of the climate and biomes, we show that human sites clustered in areas with increased terrain roughness, corresponding to higher levels of biodiversity. We find a gradual increase in human habitat preferences toward rough terrains until about 1.1 million years ago (Ma), followed by a 300 thousand-year-long contraction of the ecological niche. This period coincided with the Mid-Pleistocene Transition and previously hypothesized ancestral population bottlenecks. Our statistical analysis further reveals that from 0.8 Ma onward, the human niche expanded again, with human species (e.g., H. heidelbergensis, H. neanderthalensis, and H. sapiens) adapting to rougher terrain, colder and drier conditions, and toward regions of higher ecological diversity. [ABSTRACT FROM AUTHOR]

Shorebirds play a crucial role in assessing the health of coastal ecosystems due to their life history, behaviour, migratory patterns, and feeding preferences. Many shorebird species are experiencing population declines worldwide, driven by habitat loss and climate change. Understanding these challenges requires extensive data on their distribution and breeding ecology. The Kentish Plover (Anarhynchus alexandrinus) is a small shorebird that constructs its nests on sandy beaches. However, there is a scarcity of data regarding the reproductive ecology of this species in many areas, including the Molise region of Southern Italy. This study aimed at assessing the potential role of environmental variables derived from remote sensing to model current and future Kentish Plover nesting habitat suitability accounting for future scenarios of coastal dynamics in 2040. Data on Kentish Plover nests were collected along the Molise coast over several years and used to calibrate ecological niche models (ENMs) relying on environmental variables derived from coastal images. Kentish Plover nesting habitat suitability was mostly affected by distance from open sand, artificial surfaces, shoreline, and herbaceous vegetation and forested areas. The study predicts an average decline of more than 22% in suitable nesting environments for the Kentish Plover within the next two decades. Results indicated that our modelling approach can offer valuable insights for the conservation strategy of Kentish Plover in the region. In conclusion, we assert that preserving the nesting habitat of the Kentish Plover will not only safeguard this species, but also other species that inhabit similar environments, along with providing protection for coastal landscapes and associated ecosystem services. [ABSTRACT FROM AUTHOR]

Quantifying the degree of ecological specialization of animals is essential for understanding the evolution of resource use in changing environments. Stable isotope analysis (SIA) is a powerful tool for investigating the ecological niches of animals and providing insights into their diet. This study focused on the ecological role of two coastal species of ants, Camponotus morosus and Dorymyrmex goetschi, in Chile. Their seasonal isotopic niches were characterised using carbon (δ13C) and nitrogen (δ15N) analysis. This was done on El Tabito Beach, a coastal area with a pronounced seasonality. The results indicated unique niches for each species and variation between them across seasons. While C. morosus maintained a consistent niche breadth throughout the year, D. goetschi displayed a narrower niche in summer. Our analyses showed that terrestrial-derived carbon constituted the primary food resource for both species of ants, with a slight increase in the marine component in summer. Overall, the results highlight seasonal variations in isotopic signatures, niche breadth, and diet composition and underscore the importance of considering temporal dynamics in ant ecology and, in particular, in trophic interactions. [ABSTRACT FROM AUTHOR]

Movement is a key means by which animals cope with variable environments. As they move, animals construct individual niches composed of the environmental conditions they experience. Niche axes may vary over time and covary with one another as animals make tradeoffs between competing needs. Seasonal migration is expected to produce substantial niche variation as animals move to keep pace with major life history phases and fluctuations in environmental conditions. Here, we apply a time-ordered principal component analysis to examine dynamic niche variance and covariance across the annual cycle for four species of migratory crane: common crane (Grus grus, n = 20), demoiselle crane (Anthropoides virgo, n = 66), black-necked crane (Grus nigricollis, n = 9), and white-naped crane (Grus vipio, n = 9). We consider four key niche components known to be important to aspects of crane natural history: enhanced vegetation index (resources availability), temperature (thermoregulation), crop proportion (preferred foraging habitat), and proximity to water (predator avoidance). All species showed a primary seasonal niche "rhythm" that dominated variance in niche components across the annual cycle. Secondary rhythms were linked to major species-specific life history phases (migration, breeding, and nonbreeding) as well as seasonal environmental patterns. Furthermore, we found that cranes' experiences of the environment emerge from time-dynamic tradeoffs among niche components. We suggest that our approach to estimating the environmental niche as a multidimensional and time-dynamical system of tradeoffs improves mechanistic understanding of organism-environment interactions. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions We test the relationship between the voluntary thermal maximum (VTMax; the temperature at which an individual actively retreats to a colder site) and geographical/environmental features in the distribution of South American pitvipers. Additionally, we explore the evolution of environmental temperatures and VTMax in species' ranges.South America.South American pitvipers of the genera Bothrops and Bothrocophias.We experimentally measured the VTMax of 15 species of South American pitvipers. We explored the relationship between VTMax and geographical/environmental features (e.g., latitude, topographic complexity and temperature) with PGLS regressions. Additionally, we explored the evolution of maximum (TMax) and minimum (TMin) environmental temperatures, as well as the Thermal Niche Breadth (TNB) and VTMax, using ancestral state reconstruction and testing for phylogenetic signal.Mean VTMax values for South American pitvipers clustered primarily within the 34°C–36°C range, exhibiting little variation among species or clades. No significant correlations were found between VTMax and climatic or geographic variables. Furthermore, our analysis revealed that these snakes are absent from regions where maximum temperatures surpass their preferred thermal tolerances. Ancestral state reconstruction indicated divergent evolutionary pathways for thermal limits among species, independent of phylogenetic relationships.South American pitvipers unexpectedly exhibit similar voluntary thermal maximum values across a wide range of habitats and despite distinct phylogenetic relationships. Our results indicate that there is no strong climatic niche conservatism for South American pitvipers, with a likely weak selective pressure of VTMax. [ABSTRACT FROM AUTHOR]

Background: As blackgram cultivation is majorly spread in rain fed areas, breeding short duration and high yielding blackgram varieties is of profound importance to tackle terminal moisture stress and reap impressive yields by breaking the yield plateau. Hence, the present study was aimed to identify highly heterotic cross combinations for yield and earliness. Methods: Six parents along with 15 F1s were evaluated (rabi, 2019) for seed yield and its component traits along with earliness to estimate the magnitude of heterosis. Result: The cross LBG-752 x TBG-104 exhibited heterosis estimates in desirable direction for yield and earliness. The next best crosses were LBG-752 x PU-31, TU-40 x TBG-104, LBG-752 x TU-40 and IPU-2-43 x TBG-104. Because of its autogamous genetic architecture and biological constraints in large scale economic hybrid seed production, heterosis could be exploited only by isolating the early maturing and high yielding segregants followed by bi-parental or recurrent selection in early segregating generations and single plant selection in subsequent generations that would result in short duration and high yielding blackgram variety that fits well into different ecological niches. [ABSTRACT FROM AUTHOR]

The interactions between hosts and the gut microbiota are intricate and can significantly affect the ecology and evolution of both parties. Various host traits, including taxonomy, diet, social behaviour, and external factors such as prey availability and the local environment, all play an important role in shaping composition and diversity of the gut microbiogta. In this study, we explored the impact of intestinal microorganisms on the host in adapting to their respective ecological niches in two species of snakes. We collected feces from Lycodon rufozonatus and Lycodon rosozonatus from different geographical locations and used 16S rRNA gene sequencing technology to sequence the v3‐v4 region. The results revealed that there was no significant difference in the alpha diversity of intestinal microorganisms between L. rufozonatus and L. rosozonatus. The gut microbiota of all individuals comprised four main phyla: Pseudomonadota, Bacteroidota, Bacillota, and Actinomycetota. At the genus level, the genus Salmonella dominated the enterobacterial microbiota in the samples from Hainan, while there was no obvious dominant genus in the enterobacterial microbiota of the samples from the other four localities. Comparative analysis of enzyme families annotated to the gut microbiota between L. rufozonatus and L. rosozonatus from the four sampling regions by CAZy carbohydrate annotation revealed that nine enzyme families differed significantly in terms of glycoside hydrolases (GHs). In addition, we compared the composition of gut microbial communities between L. rufozonatus and L. rosozonatus and investigated the impact of the differences on their functions. Our results will provide insights into the coevolution of host and gut microbes. [ABSTRACT FROM AUTHOR]

The foraging strategies of sympatric ungulates with similar ecological niches are important for understanding ecological niche differentiation, resource utilization, competition, and coexistence and for understanding the ecological impacts on plant communities in the ecosystem. The behavior of the wapiti (Cervus elaphus) and Siberian roe deer (Capreolus pygargus) foraging on Japanese yew (Taxus cuspidata) has affected its succession and renewal in the northeastern forests of China, which has become an urgent problem for the relevant departments. This study analyzed the foraging strategies of the wapiti and Siberian roe deer on Japanese yew from July 2021 to January 2024 using field investigations and infrared camera monitoring in the Muling National Nature Reserve, Heilongjiang Province, China. It was found that the wapiti and Siberian roe deer have different foraging strategies in terms of time, space, and behavior. Temporally, they both preferred to forage for the saplings of the Japanese yew during the winter season, the degree of overlap in foraging rhythms was medium (Dhat1 = 0.67), and the diurnal foraging activity index (DRAI) of the wapiti was larger than that of the Siberian roe deer. Spatially, the suitable foraging habitat of the Siberian roe deer was twice that of the wapiti, and their overlap was low in the location and direction of saplings and the distance of the seed tree. Behaviorally, the foraging intensity of the wapiti was high, and that of Siberian roe deer was low. Foraging reduced the average primary branch height, number of new branches, and length of lateral branches of saplings, and the influence of the wapiti was significantly greater than that of the Siberian roe deer. This study provides a scientific basis for solving the conservation and management problems of the deer animals foraging on Japanese yew and contributes to further understanding of the competition‐coexistence mechanism of sympatric species. [ABSTRACT FROM AUTHOR]

Diversification is frequently associated with change—anything from colonizing a new area to evolving a new trait. Once a lineage changes, the organisms may be able to exploit previously unavailable ecological opportunities and release pressures from predators, parasites, and competitors, which may increase the speciation rate. Modern teiid lizards originated in South America but managed to colonize and diversify in North America. We assessed whether geographic distribution, body size, and body temperatures are associated with teiid diversification using GeoHiSSE and inverse equal‐splits statistics with simulation tests. We also estimated speciation rates with MiSSE to account for the effect of unmeasured variables. Moreover, we assessed the ecological niche overlap between North American (including Caribbean) teiids and their sister clade in South America. Our results indicate that only distribution range affected diversification, but we discuss that the available data might not have been enough to assess the effect of body temperatures. We also show that North American teiids have a broader ecological niche encompassing almost all environmental conditions used by their sister clade in South America but expanding mainly toward arid areas. Our results suggest that this expansion significantly impacted teiid diversification due to the seizing of ecological opportunities or ecological release, but we do not discard possible effects of phenotypic evolution. [ABSTRACT FROM AUTHOR]

Hatching synchronisation is widespread in oviparous taxa. It has been demonstrated that many species use sounds to coordinate synchronous hatching, being widespread among archosaurs (birds and crocodilians). Recent studies have shown that some turtle species produce vocalisations from within the egg, but the role of this behaviour in synchronising hatch is untested. The small amount of information about sound production by turtle embryos, limited to a handful of closely related species, precludes any inferences based on differences in their ecology, reproductive behaviour and phylogenetic context. With the goal to investigate if coordinated synchronous behaviour is mediated by within‐egg vocalisations in turtles, we recorded clutches from six different turtle species. The selected animals present different ecological and reproductive niches and belong to distinct phylogenetic lineages at the family level. We aimed to understand: (1) what is the phylogenetic distribution of within‐egg vocal behaviour among turtles; (2) if asynchronous turtle species vocalise from within the egg; (3) if clutch size influences synchronous behaviour and (4) if within‐egg turtle calls follow any phylogenetic signal. The new evidence provides light to the current knowledge about synchronous behaviour and within‐egg calls, challenging previous hypothesis that within‐egg sounds are accidentally produced as side‐effects of other behaviours. [ABSTRACT FROM AUTHOR]

Amphibians have the least studied life histories among vertebrates, although they have unique and the most diverse life histories within this group. We compiled a new dataset on adult body mass and 16 other life history traits of 2069 amphibian species across three orders (1796 frogs, 236 salamanders, 37 caecilians). These traits characterise fecundity, offspring development from egg deposition to metamorphosis and adult life. We established allometric models on traits for all amphibians and each of the three orders to assess a potential scaling of traits to body mass and then checked whether allometric slopes were consistent with two different metabolic scaling exponents. Further, we examined a possible fast‐slow continuum in all amphibians, as well as in each of the two orders frogs and salamanders by applying principal component analysis (PCA) to five traits. Our allometric models indicated a positive scaling to body mass for 11 traits across all amphibians, 12 in frogs, and 10 in salamanders, and for five out of eight traits analysed in caecilians. Allometric slopes on most traits characterising offspring development were not significant. All slopes did not support a three‐quarter metabolic scaling exponent, whereas slopes on age at maturity and maximum longevity were consistent with an amphibian metabolic scaling exponent of 0.88. As in fishes, reptiles, birds, and mammals, the first axes of our PCAs indicated a body mass‐dependent fast‐slow continuum in amphibians. Amphibian species of slow life histories have larger body masses, later sexual maturities and longer lifespans and lay more and larger eggs than species of fast life histories, a pattern also known from reptiles. The second axes indicated a trade‐off between egg size and number. As this trade‐off was nearly independent of body mass, we hypothesise that amphibians have occupied a broad range of ecological niches without evolutionary changes in body mass. [ABSTRACT FROM AUTHOR]

Lichen-feeding termites occupy a distinctive ecological niche. This feeding behavior underscores a complex interplay between the termites' digestive abilities and the biochemical properties of lichens, known for their resilience and production of secondary metabolites. Understanding the dietary preferences and digestive mechanisms of these termites offers insights into their ecological roles and the evolutionary adaptations that enable them to exploit such a specialized food source. We conducted experiments with Constrictotermes cyphergaster, feeding it with different combinations of its natural food sources: wood bark and lichen from host trees. Gut microbial communities were analyzed through 16S rRNA sequencing and shotgun metagenomics. Our results revealed that a diet containing lichens induces a shift in microbiota composition and increases the abundance of genes encoding an AA3 enzyme with a role in lignin digestion. This study emphasizes the potential role of lichens in enhancing the digestive capabilities of termites, highlighting the intricate relationships between diet, gut microbiota, and enzymatic activity in Termitidae. [ABSTRACT FROM AUTHOR]