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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]

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]

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]

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 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]

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]

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]

Background: Fungi play a crucial role in the development of rapeseed and influencing the functioning of agroecosystems. However, the fungal composition and function in spring rapeseed on the Qinghai-Tibet Plateau (QTP) remain unclear. Methods: The agronomic traits, rhizosphere soil properties, and fungal communities across multiple niches within seven cultivars of Brassica rapa L. and Brassica napus L. were investigated using cultivation, physiological assay, and high-throughput sequencing. Results: We found significant differences in growth indices, yields and fungal diversity among leaf, stem, and root compartments of B. napus, especially in late-maturing cultivars, compared to B. rapa. Interestingly, defense-related indices and fungal diversity in rhizosphere soil exhibited the opposite trend. A total of 12 phyla, 55 orders and 200 genera were identified. The predominant genera were Olpidium (66.29%), Lactarius (18.37%), Verticillium (1.99%), Mortierella (0.78%) and Cystofilobasidium (0.56%). The rhizosphere soil had a higher abundance of Olpidium and Mortierella than other ecological niches, while the stem harbored more Lactarius and Verticillium. In addition, 46 key genera were widespread across all niches and cultivars, and 19 biomarkers were significantly enriched, with saprotroph-symbiotroph, symbiotrophs and pathotroph-symbiotroph trophic groups dominating. Alternaria isolated from rapeseed, which was also identified as one of the most abundant, key and biomarker genera, effectively facilitated the germination of B. rapa under chilling and drought stress. Conclusions: The joint influence of numerous important fungal genera can promote the growth and yield of rapeseed. Our results provide valuable insights into the complex relationship between rapeseed and fungal communities on the QTP. [ABSTRACT FROM AUTHOR]

Characterizing the genetic diversity of a species is crucial for understanding the factors that influence its local dispersion and population dynamics. Additionally, it provides insights into local processes that may affect the distribution of other species. Lineus sanguineus (Rathke, 1799) is a widely distributed species commonly found on fouling fauna along rocky shores. This species can reproduce asexually by fissiparity, and its pilidium larva facilitates dispersal, similar to other heteronemerteans. The present study utilized a population genetics approach combined with Ecological Niche Modeling analysis to evaluate L. sanguineus populations along the Brazilian coast. We used sequences from two mtDNA regions, 16S ribosomal RNA (16SrRNA) and cytochrome c oxidase subunit 1 (COI), and one nuclear region, Internal Transcribed Spacer 1 (ITS-1), from 85 specimens sampled in nine locations. Genetic diversity analysis revealed greater genetic variation for the ITS-1 marker compared to mtDNA, as evidenced by higher intrapopulation diversity values. There was no clear geographic pattern, and the AMOVA analysis revealed low to moderate genetic structuring and high connectivity among sampled localities, with most of the genetic variation contained within populations. The pairwise FST results indicate high genetic structuring between the Northeast and localities along the South and Southeast of Atlantic coastlines. This pattern suggests that Brazilian oceanic currents play an important role in species connectivity. The paleodistribution pattern demonstrated that the colonization could have occured from the South to the Northeast of the continent. These results reinforce that sexual reproduction and larval dispersion play a vital role in the connectivity of these Southwest Atlantic populations and that oceanographic currents, rafting and artificial transport facilitate these processes. [ABSTRACT FROM AUTHOR]

The niche of aphids is largely defined by their consumption of plant phloem sap and its composition, including nutrients and specialized metabolites. Niche construction is the change of the environment by organisms, which may influence the fitness of these organisms and their offspring. To better understand interactions between plants and aphids, it is necessary to investigate whether aphids modify the chemical composition of the phloem sap of their host plants and whether conspecifics are affected by previous infestation. In the current study, ears of wheat (Triticum aestivum) plants were infested with clonal lineages of the English grain aphid (Sitobion avenae) or were left uninfested. The metabolic composition of ear phloem sap exudates was analyzed through amino acid profiling and metabolic fingerprinting. Aphids of the clonal lineages were either put on previously aphid-infested or on uninfested ears and their colony sizes followed over time. Furthermore, it was investigated whether aphids choose one treatment group over another. Sitobion avenae infestation affected the relative concentrations of some metabolites in the phloem exudates of the ears. Compared to uninfested plants, the relative concentration of asparagine was higher after aphid infestation. Colonies grew significantly larger on previously aphid-infested ears, which the aphids also clearly chose in the choice experiment. The pronounced positive effect of previous infestation on aphid colonies indicates niche construction, while the choice of these constructed niches reveals niche choice by S. avenae on wheat. The interplay between these different niche realization processes highlights the complexity of interactions between aphids and their hosts. [ABSTRACT FROM AUTHOR]

The community ecology and microhabitat association of tanaidaceans in three rocky intertidal areas of central-eastern Taiwan were investigated in April and August 2012. Typhoon Saola impacted the study areas 2 weeks before the August survey, providing an opportunity to examine community responses to extreme wave exposures. Among the 3,622 individuals and 12 species collected, Chondrochelia taitungensis, Paraleptochelia setosa, Synapseudes hansmuelleri, Zeuxo shitipingensis, and Zeuxo zorro comprised approximately 95% of the total abundance. Surprisingly, the tanaidacean abundance, diversity, composition, and microhabitat specialization exhibited little impact from the typhoons, indicating that these tube dwellers can resist such extreme wave impacts. Spatial variation in the abundance of dominant species, species diversity, and composition among tanaidacean communities was attributed to differences in rock formations, microhabitat availability, and species' limited dispersive ability and potential interspecific competitive interactions. While the dominant species exhibited a more generalized microhabitat association, the relatively rare species displayed some specialization. This study pioneers investigation into microhabitat associations among rocky intertidal tanaidaceans. Future studies should incorporate sustained monitoring of community dynamics and microhabitat associations, integrating essential climatic variables into the analysis to predict community responses to natural or anthropogenic disturbances. [ABSTRACT FROM AUTHOR]

The introduction of non-native fish species poses a significant threat to biodiversity. In Spain, the common carp Cyprinus carpio (Linnaeus, 1758) and the bleak Alburnus alburnus (Linnaeus, 1758) are both established and sometimes co-occurring non-native species. Here, we investigated the trophic ecology of these species using an integrative approach, combining dietary and stable isotope analyses, to understand seasonal variations in their feeding ecology and potential niche overlap. We found a variable pattern for the gonadosomatic index of the two species in spring and autumn, suggesting the occurrence of extended reproductive periods for both A. alburnus and C. carpio. The gut content and isotopic niche analyses showed seasonal niche shifts, as well as interspecific niche partitioning and potential feeding competition. Notably, we found remains of small fish in the gut of both species and one entire individual of Gambusia holbrooki (Girard, 1859) in the carp gut, highlighting the potential of both species to prey also upon native fish fry or juveniles. Moreover, A. alburnus showed an ontogenetic shift toward prey from higher trophic levels and from the littoral/benthic environment, while C. carpio showed an increase in the proportion of prey from the pelagic environment with size. [ABSTRACT FROM AUTHOR]

Wildfires are considered a major disturbance to forest ecosystems in the Mediterranean countries of Southern Europe. Although ground-dwelling macroinvertebrates are crucial to many soil functions, there is a fundamental lack of understanding of how wildfires impact this community in the immediate term and of the role of stones in their survival. Hence, in the present study we assessed the immediate effects of wildfires in the ground-dwelling macroinvertebrate community found under stones by comparing communities in burnt and non-burnt Mediterranean oak forests. Our results revealed that stones allowed the survival of many taxa in the burnt area. However, abundance, richness, diversity, and equitability per stone were significantly lower at the burnt than unburnt sites. Furthermore, the results also showed that richness and abundance increased significantly with increasing stone depth and area, both at the burnt and unburnt sites. Significant changes at the trophic level were observed in the burnt area comparing to the unburnt, particularly a decline in predators. No significant differences were identified concerning habitat associations among taxa. Overall, this study stressed the role of stones as microhabitats and refuge for the ground-dwelling macroinvertebrate community during wildfires. [ABSTRACT FROM AUTHOR]

Coral reefs are among the most biodiverse ecosystems on Earth, largely due to the structural complexity created by corals. Coral habitat is crucial refuge for numerous small animals, and competition for habitat can structure populations if in short supply. Reefs in Hawai'i are largely dominated by the small branching coral Pocillopora meandrina, which supports diverse communities of fishes and invertebrates. Two species of nocturnal scorpionfishes, Sebastapistes coniorta and S. galactacma, are particularly common in P. meandrina, inhabiting the complex branching morphology of their host corals during the day and feeding in and around these corals at night. Surveys of scorpionfishes in 458 P. meandrina between 3 and 22 m deep along the south and west shores of O'ahu revealed inverse depth distributions over which these species occurred in P. meandrina. Sebastapistes coniorta almost exclusively occurred in coral colonies between 5 and 10 m deep, while S. galactacma were found across all depths surveyed, though were far more common and abundant in deeper coral colonies (15–20 m) below the range of S. coniorta. Further, measurements of host colony morphometrics revealed that these species appeared to use microhabitat in subtly different ways. The larger-bodied species, S. coniorta, was more commonly found in P. meandrina with wider spaces between branches, while the smaller-bodied species was negatively associated with wider branch spacing. These patterns indicate habitat partitioning between S. coniorta and S. galactacma at both the reef and colony scale, which may explain how these species are able to coexist on reefs in Hawai'i. [ABSTRACT FROM AUTHOR]

Mountainous regions typically harbour high plant diversity but are also characterised by low sampling intensity. Coarse-scale species distribution models can provide insights into the distribution of poorly sampled species, but the required bioclimatic data are often limited in these landscapes. In comparison, several environmental factors that vary over relatively fine scales in mountain environments (e.g. measures of topography) can be quantified from remotely-sensed data, and can potentially provide direct and indirect measures of biologically-relevant habitat characteristics in mountains. Therefore, in this study, we combine field-sampled floristic data with environmental predictors derived from remotely-sensed data, to model the ecological niches of 19 montane plant species in the Maloti-Drakensberg mountains, South Africa. The resulting models varied considerably in their performance, and species showed generally inconsistent responses to environmental predictors, with altitude and distance to watershed being most frequently included in models. These results highlight the species-specificity of the forb species' environmental tolerances and requirements, suggesting that environmental change may result in re-shuffling of community composition, instead of intact communities shifting along gradients. Furthermore, while the relatively high importance of altitude (a proxy for temperature) and topographic wetness index (a proxy for soil moisture) suggest that the flora of this region will be sensitive to shifts in temperature and rainfall patterns, several non-climatic environmental variables were also influential. Our findings indicate that local response to climate change in mountains might be especially constrained by soil type and topographic variables, supporting the important influence of non-climatic factors in microclimatic refugia dynamics. [ABSTRACT FROM AUTHOR]

More heterogeneous environments allow for greater availability of ecological niches, thus favoring greater species diversity. However, it is not yet established how heterogeneity influences taxonomic and functional beta diversity. Therefore, we aimed to determine how environmental heterogeneity affects the patterns of taxonomic and functional beta diversity of planktonic microcrustaceans in reservoirs in different regions (semiarid and humid) in Northeast Brazil, in addition to verifying the influence of dry and rainy periods on these measures. Sampling from the semiarid region was carried out between 2013 and 2016, while samples from the humid region were collected between 2019 and 2021. Environmental heterogeneity and taxonomic and functional beta diversity were greater in the semiarid region, regardless of the hydrological period. However, regardless of the region, taxonomic beta diversity was greater during the dry period, while functional beta diversity did not differ between periods. Both types of diversity were driven mainly by local factors in the semiarid region, considered a region of high environmental heterogeneity due to the geomorphological and climatic characteristics that differentiate it from other regions. This type of study reinforces the need to conserve these reservoirs, especially those located in the semiarid region, as they support greater variability in species composition and functional traits. [ABSTRACT FROM AUTHOR]

Climate change and invasive species represent two intertwined global environmental challenges profoundly affecting freshwater ecosystems. This study uses Ecological Niche Modeling along with risk screening to delve into the preferences and potential distribution of Potamopyrgus antipodarum, an invasive species, in relation to climate zones and habitat types, shedding light on the critical importance of coastal wetlands and high soil organic carbon content in shaping habitat suitability. Our findings underscore that P. antipodarum exhibits a distinct affinity for cool temperate, moist climates, as well as temperate floodplain rivers, wetlands, and coastal areas. Notably, coastal wetlands, endowed with elevated soil organic carbon levels, emerged as pivotal habitats for this species. Projections indicated a significant expansion in North America, potentially extending into South America. Türkiye reveals an intriguing alignment between its habitat and the natural distribution areas of P. antipodarum, presenting potential for habitat contraction while still retaining a broader range compared to other regions. These potential expansions were predominantly driven by climate suitability, playing a pivotal role in the invasiveness of P. antipodarum, with anticipated future climate regimes exerting substantial influence on its dispersal capabilities. [ABSTRACT FROM AUTHOR]

The introduction of the Nearctic predaceous stink bug species, (Perillus bioculatus) was attempted multiple times in various countries throughout Europe to mitigate the damage caused by the invasive and harmful pest species, the Colorado potato beetle (Leptinotarsa decemlineata). Though these attempts were thought to be unsuccessful for decades, more recent data elucidated that the species have established small self-sustaining populations in the Balkans Peninsula, Southern Russia, and Türkiye and recently began to expand. In the past years, the European range of the species reached Eastern Europe. After the first individuals were found in Hungary in October 2023 a citizen science campaign was launched to investigate the distribution of the species in the country. By June 2024 it became evident that the species is established throughout the country. Furthermore, observations regarding beetle larvae and moth caterpillars as alternative prey were reported supporting the previous assumptions that the naturalization and expansion of the species in Europe is facilitated by dietary drift. Here, we summarize the knowledge on the European presence of the two-spotted stink bug and formulate hypotheses regarding its future distribution and the impact of the species on the insect communities of the newly colonized areas. [ABSTRACT FROM AUTHOR]

While the interbreeding of Homo neanderthalensis (hereafter Neanderthal) and Anatomically modern human (AMH) has been proven, owing to the shortage of fossils and absence of appropriate DNA, the timing and geography of their interbreeding are not clearly known. In this study, we applied ecological niche modelling (maximum entropy approach) and GIS to reconstruct the palaeodistribution of Neanderthals and AMHs in Southwest Asia and Southeast Europe and identify their contact and potential interbreeding zone during marine isotope stage 5 (MIS 5), when the second wave of interbreeding occurred. We used climatic variables characterizing the environmental conditions of MIS 5 ca. 120 to 80 kyr (averaged value) along with the topography and coordinates of Neanderthal and modern human archaeological sites to characterize the palaeodistribution of each species. Overlapping the models revealed that the Zagros Mountains were a contact and potential interbreeding zone for the two human species. We believe that the Zagros Mountains acted as a corridor connecting the Palearctic/Afrotropical realms, facilitating northwards dispersal of AMHs and southwards dispersal of Neanderthals during MIS 5. Our analyses are comparable with archaeological and genetic evidence collected during recent decades. [ABSTRACT FROM AUTHOR]

The Fall armyworm, Spodoptera frugiperda is the most notorious invasive pest species on maize, recently reported in India. The continuous spread of Fall armyworms to new ecological niches raises global concern. The current study is the first in India to forecast the suitability of a habitat for S. frugiperda using a maximum entropy algorithm. Predictions were made based on an analysis of the relationship between 109 occurrence records of S. frugiperda and pertinent historical, current, and predicted climatic data for the study area. The model indicated that S. frugiperda could thrive in different habitats under the current environmental circumstances, particularly in the west and south Indian states like Maharashtra, Tamil Nadu, and Karnataka. The model predicted that areas with higher latitudes, particularly in Uttar Pradesh, Odisha, West Bengal, and some portions of Telangana, Rajasthan, Chhattisgarh, and Madhya Pradesh, as well as some tracts of northeastern states like Assam and Arunachal Pradesh, would have highly climate-suitable conditions for S. frugiperda to occur in the future. The average AUC value was 0.852, which indicates excellent accuracy of the prediction. A Jackknife test of variables indicated that isothermality with the highest gain value was determining the potential geographic distribution of S. frugiperda. Our results will be useful for serving as an early warning tool to guide decision-making and prevent further spread toward new areas in India. [ABSTRACT FROM AUTHOR]

Understanding how population structure and demography are determined is a central theme in marine biogeography. While historical events, such as past climate change, are important determinants, the mechanisms by which they act are not well understood in many marine species. In this study, the population structure of the Japanese, marine intertidal gastropod Lunella correensis was investigated to determine whether it has been affected by past environmental changes. A genome-wide SNP analysis, L. correensis showed a genetic gradient along the coast and a weak genetic differentiation between sites in the Sea of Japan and the Pacific Ocean. Demographic inference suggests that the effective population size expanded and shrunk in response to periods of rapid warming and cooling due to past climate change. Further, ecological niche modelling suggests that the population size of L. correensis increased by advancing into the Sea of Japan during rapid warming after the Last Glacial Maximum. Notably, our analyses suggest that recent human activities may have influenced the effective population size of this species. Specifically, the period of reduction in the population size coincides with environmental changes and habitat loss associated with development along the Japanese coastal area. Thus, these results emphasize that the genetic structure and demography of marine species have been influenced by past environmental change around the Japanese Archipelago. [ABSTRACT FROM AUTHOR]

Utilising multiple lines of evidence for palaeoenvironmental reconstruction improves our understanding of the past landscapes in which human populations interacted with other species. Illuminating such processes is key for a nuanced understanding of fundamental transitions in human history, such as the shift from hunting and gathering to farming, and allows us to move beyond simple deterministic interpretations of climate-driven innovation. Avifaunal remains provide detailed indications of complex multi-species interactions at the local scale. They allow us to infer relationships between human and non-human animals, but also to reconstruct their niche, because many bird species are sensitive to specific ecological conditions and will often relocate and change their breeding patterns. In this paper, we illustrate how novel evidence that waterfowl reproduced at Levantine wetlands, which we obtained through biomolecular archaeology, together with modern ornithological data reveals conditions of wetlands that are conducive for breeding waterfowl. By understanding the interplay between wetland productivity cycles and waterfowl ecology, we argue that human modifications to the environment could have promoted wetland productivity inviting waterfowl to remain year-round. Within this landscape of "mutual ecologies", the feedback resulting from the agency of all species is involved in the construction of the human niche. [ABSTRACT FROM AUTHOR]

For quantifying m-dimensional ( m ≥ 3 ) niche regions and niche overlaps using a copula-based approach, commonly used copulas, including Archimedean and elliptical copula families, are unsatisfactory alternatives in characterizing a complex dependence structure among multiple variables, especially when bi-variate copulas characterizing dependency structures of two-dimensional sub-variables differ. To solve the problem, we improve the copula-based niche space modeling approach using simplified vine copulas, a powerful tool containing various bi-variate dependence structures in one multivariate copula. Using four simulated data sets, we then check the performance of simplified vine copula approximation when the simplifying assumption is invalid. Finally, we apply the improved copula-based approach to quantifying a three-dimensional niche space of a real case of Swanson et al. (Ecology 96(2):318–324, 2015. https://doi.org/10.1890/14-0235.1) and discover that among various simplified vine and other flexible multi-dimensional copulas, non-parametric simplified vine copula approximation performs best in fitting the data set. In the discussion, to analyze differences in calculating niche overlaps caused by using different copulas, we compare non-parametric simplified vine copula approximation with non-parametric and parametric simplified vine copula approximation, elliptical copula, Hierarchical Archimedean copula estimation, and empirical beta copula and give some comments on the results. [ABSTRACT FROM AUTHOR]

The tight relationship of niche breadth (i.e., environmental tolerance and resource use) with ecomorphological traits and extinction risk makes the study of habitat niche breadth (i.e., habitat heterogeneity; HB) crucial to understanding the species' ecological niche and macroecological aspects. Additionally, HB has been associated with the species extinction risk (ER) due to human activity. Bats can be ideal for understanding HB's ecological and conservation relevance due to their diverse diet and other traits, as well as the high number of threatened species. Here, we studied the association between HB, trophic guild (TG), body mass (BoM), and extinction risk (ER) in phyllostomid bat species using a phylogenetic comparative approach. Our results showed that the TG, not BoM, is significantly associated with HB in phyllostomid bats. Omnivorous and sanguinivorous bats have a wider HB than plant-eating and insectivorous bats. Regarding the ER of bats, our results showed that species without risk have wider HB than species at risk. The HB of species without conservation status does not differ from at-risk species, which suggests that at least some species should be considered at risk. In conclusion, our study suggests that diet is a relevant trait that influences the macroecological dynamic of phyllostomid bats due to its relation with HB. Additionally, we provided evidence supporting HB's use as an ER predictor. Finally, we discussed the necessity of finding alternative and quicker ways to assess the ER of the species. [ABSTRACT FROM AUTHOR]

Protecting rare and endangered species from habitat loss caused by climate and land use changes is crucial for stopping unprecedented biodiversity loss. Data on species' future range shifts is crucial in protected area management planning to establish proper refuges. This study focused on identifying the suitable habitat, vulnerabilities, and conservation gaps of Vatica guangxiensis—a canopy tree species endemic to the subtropical forests of southwest China and listed as Endangered in the IUCN Red List— through Maxent species distribution modeling using current and future climate data. Results showed that the predicted suitable habitats for V. guangxiensis under current climate were more extensive than its known range, encompassing parts of China, northern Laos, northern Vietnam, and eastern Myanmar. They are most likely to be in wetter regions with acidic soils. However, these habitats were predicted to decrease by 90% and shift to lower latitudes and higher elevations by 2081–2100 due to climate change, which leads to habitat loss for five out of twelve current wild populations, as well as severe fragmentation and reduced protected area coverage. Our findings demonstrate the potential for new field discoveries of V. guangxiensis based on its predicted distribution under current climate, but also show the vulnerability of its habitats under future climate change. We present a dire outlook for V. guangxiensis and highlight the need for field discovery of new populations and the establishment of ex situ populations that are explicitly guided by suitable habitat predictions. Furthermore, this study can contribute to the expansion of climate-informed protected areas in the Indochina region, to support the flagship '30 × 30' target for protected areas under the Kunming-Montreal Global Biodiversity Framework. Lastly, our findings elucidate the importance of transboundary conservation efforts, such as the Lancang-Mekong Cooperation Five-Year Action Plan, in preserving biodiversity and achieving global conservation goals. [ABSTRACT FROM AUTHOR]

The phylogenies of the plague microbe (Yersinia pestis), reconstructed on the basis of an advanced molecular genetic (MG) approach, are not congruent with the facts accumulated by classical scientific areas: ecology, biogeography, paleontology, epizootiology, and others. The MG approach cannot name the original host of the plague pathogen and reliably characterize the root of the phylogenetic tree. This deficiency is compensated by the ecological (in a broad sense) (ECO) approach, which operates with such ecological, phylogeographic, and biogeographic categories as geographical population, subspecies, range, ecological niche, and direct kinship. Y. pestis, the "blood dweller" of warm-blooded rodent hosts, is transmitted through flea bites and is unique in the family of predominantly intestinal bacteria Yersiniaceae (Enterobacteriaceae). According to the ECO approach, its uniqueness is associated with the origin in the populations of its primary host, the Mongolian marmot (Marmota sibirica), in unique circumstances, in which the marmot population was infected with pseudotuberculosis not by the traditional alimentary way in grasslands, but in a traumatic way during hibernation. The identification of the original host of the plague pathogen opens up broad prospects for studying its evolutionary history (speciation and intraspecific diversification) and improving the methodology of ecological, geographic, phylogeographic, and phylogenetic studies of this especially dangerous pathogen. [ABSTRACT FROM AUTHOR]

Mountainous regions are biodiversity hotspots with a high rate of endemism. However, these areas are witnessing accelerated warming, that threaten biodiversity and potentially causes habitat shrinkage for many species. Our study focuses on one such species, Andesiops peruvianus, a native mayfly of the mountains regions of South America. Our objectives were to analyze the genetic diversity of the 16 S gene in several populations, to assess their climate niche and potential distribution under future climate change scenarios. For genetic analysis samples were collected and sequenced from different sites across the South America (Argentina, Bolivia, Ecuador, and Colombia) and combine with the GenBank database. We identified 17 unique haplotypes based on 16 S gene, grouping them into two mains lineages: northern (Colombia and Ecuador) and southern (Bolivia and Argentina). Niche analysis showed a significant divergence between the northern and the southern lineages, suggesting distinct ecological niches. As future climatic changes were examined, both groups were observed to potentially lose about half of their suitable habitats. Habitat loss is the greatest at lower altitudes, but with some gain at higher altitudes. Isothermality and Annual Mean Temperature played a crucial role in defining habitats suitable for A. peruvianus. These features, coupled with their low thermal tolerance, might render the species particularly vulnerable to the impacts of climate change. Implications for insect conservation: This study highlights the need for targeted conservation strategies that protect and restore habitats along the altitudinal gradient to facilitate gene flow and enhance the resilience of A. peruvianus and other species to climate change. [ABSTRACT FROM AUTHOR]

Neuropteran larvae are fierce predators that use venom to attack and feed on arthropod prey. Neuropterans have adapted to diverse and sometimes extreme habitats, suggesting their venom may have evolved accordingly, but the ecology and evolution of venom deployment in different families is poorly understood. We applied spatial transcriptomics, proteomics, morphological analysis, and bioassays to investigate the venom systems in the antlion Euroleon nostras and the lacewing Chrysoperla carnea, which occupy distinct niches. Although the venom system morphology was similar in both species, we observed remarkable differences at the molecular level. E. nostras produces particularly complex venom secreted from three different glands, indicating functional compartmentalization. Furthermore, E. nostras venom and digestive tissues were devoid of bacteria, strongly suggesting that all venom proteins are of insect origin rather than the products of bacterial symbionts. We identified several toxins exclusive to E. nostras venom, including phospholipase A2 and several undescribed proteins with no homologs in the C. carnea genome. The compositional differences have significant ecological implications because only antlion venom conferred insecticidal activity, indicating its use for the immobilization of large prey. Our results indicate that molecular venom evolution plays a role in the adaptation of antlions to their unique ecological niche. A combination of methods excludes the contribution of bacteria to venom production in predacious antlions and reveals differences in neuropteran venom compositions and activities reflecting the insects' distinct ecological niches. [ABSTRACT FROM AUTHOR]

Species traits are essential for inferences on ecology and the evolution of organisms. Spiders are the most abundant and diversified terrestrial predators, playing an important role in a range of ecosystem services. Here, I present datasetse on all traits of zodariid spiders, which are known to be free-living ground-dwellers occurring on all continents (except Antarctica) with the highest species diversity in Australia. I collated the data from published resources. The datasets includes nearly 100 000 trait records on all (90) genera and almost all species (1249) of the family. The majority of the 88 traits collected are morphometric, followed by those relating to ecology, reproduction, and physiology. Morphometric traits were available for the majority of species. Other trait classes were only available for some species. I provide a standardized classification of selected categorical traits (habitat, microhabitat, retreat type, circadian activity, prey, primary defensive, and predators). This is the first complete database of traits of a whole spider family, which is available through the World Spider Trait database. [ABSTRACT FROM AUTHOR]

The platypus (Ornithorhynchus anatinus) is a semi-aquatic monotreme that occupies a high trophic position in the freshwater ecosystems of eastern mainland Australia and Tasmania. Platypuses are continuously exposed to anthropogenic contaminants including perfluorooctane sulfonate (PFOS). This study examined PFOS concentrations in the livers of deceased platypuses (eight wild; one captive) that were opportunistically collected across NSW over a two- and a half-year period. There was a large variation in PFOS concentrations, ranging from < 1 µg/kg to 1200 µg/kg. This study presents the first report of PFOS contamination in platypuses, revealing their PFOS levels are broadly similar to those found in river otters (Lutra canadensis) and lower than those in American mink (Mustela vison), both which occupy similar ecological niches in freshwater systems. This study raises concerns about the impact of PFOS on platypus health. [ABSTRACT FROM AUTHOR]

This study investigated morphological differences, habitat preference, and ecological niche overlap in two sympatric Capoeta species i.e., Capoeta. damascina and Capoeta umbla collected from the Sirvan river drainage. Ten environmental factors, including pH, temperature, electrical conductivity (EC), total dissolved solids (TDS), river width, river depth, flow velocity, altitude, slope, and dissolved oxygen (DO) were measured during sampling time. A total of 17 morphometric characteristics were measured using digital calipers for traditional morphometrics (TM). For the geometric morphometric method (GM), 2D pictures were taken from the left side of the fresh samples, by tpsDig2 software, and 16 landmark points were defined and digitalized to extract body shape data. The data were analyzed using t-test, Mann–Whitney, principal component analysis (PCA), and discriminant function analysis based on the P-value of Hotelling's T-squared. The ratio of the common area under the graph to the total area of habitat suitability indices was defined as the ecological niche overlap. The results showed significant differences in eye diameter, predorsal, caudal peduncle length, preanal, preventral, ventral-pectoral, body depth, and caudal peduncle depth traits (P < 0.05) in TM, and those differences in the GM were related to the position of the snout, head and body depth and caudal peduncle length i.e., C. damascina had the deeper body shape and head, and anterior the snout and caudal peduncle length. Based on the results, C. damascina prefers areas with higher pH and temperature and by increasing other studied factors, its habitat suitability decreased. The preference for C. umbla with increasing river depth and DO was increased. These two species showed low niche overlap i.e., they avoid competition in their habitat by opting for different areas in terms of river width, flow velocity, and temperature that have more depth with higher slope microhabitats. [ABSTRACT FROM AUTHOR]

The fundamental ecological niche is determined by individuals' ability to cope with abiotic conditions; however, biotic interactions (e.g., competition) can also influence species' distribution ranges, reducing the fundamental niche to the realized niche. Several species of the genera Clibanarius and Calcinus overlap in their distributions. The agonistically dominant Calcinus species inhabits mostly lower intertidal levels, while Clibanarius is more abundant in the abiotically demanding upper strata. Additionally, evidence of microhabitat competitive exclusion shows that the superior competitor, Ca. californiensis, causes the vertical displacement of Cl. albidigitus. However, it is unknown whether competitive exclusion between species of these genera has influenced their distributions at the macroecological scale. We used ecological niche models to compare the distribution and the habitat suitability of species of these genera. We used databases of species occurrences and bioclimatic and geophysical variables to model and map the species' niches. Species of the two hermit crab genera showed strong overlap in their habitat suitability. Calcinus and Clibanarius species occur in broad sympatry at the regional scale without regions of partial overlap that would indicate competitive exclusion. Therefore, competitive exclusion among species of these genera seems to act only on a microhabitat scale in the most dynamic shoreline areas. [ABSTRACT FROM AUTHOR]

We aimed to characterize the trophic ecology and test the hypothesis of niche overlap between four sympatric batoid species of the subtropical South Atlantic. Data were collected between 2017 and 2022 from two artisanal fishery communities in southern Brazil. Batoid's stomach contents were identified, separated into categories, and weighed. We calculated the Levins, Pianka's, and Prey-specific index of relative dietary importance (PSIRI) and performed a similarity test using PERMANOVA and the similarity percentage (SIMPER) for niche analysis. We analyzed 229 stomachs of four batoid species, 187 containing foods. All species showed a narrow food niche. The most important diet items for each species were Leptochaela serratorbita and Onuphidae for Dasyatis hypostigma; Nematoda for Pseudobatos horkelii; L. serratorbita, Sicyonia dorsalis and Portunidae for Rioraja agassizii and Achelous spinicarpus and fish for Sympterygia bonapartii. The analyses showed dissimilarity among the species' diets without significant niche overlap. Our results detected the absence of significant niche overlap among batoid species, suggesting other types of niche partitioning and spatiotemporal habitat variation. This information could be considered for local management plans. [ABSTRACT FROM AUTHOR]

Marine sunfishes (also known as molids) of the Family Molidae are widely distributed from tropical to temperate waters and are typically recognized as predators of gelatinous plankton almost exclusively. Despite similar morphological features and behaviors, the trophic ecology and potential interactions among species of molids remain largely unknown. We reviewed literature on the diets of each species and conducted diet analyses of three species sampled off the east coast of Taiwan. We examined diet separation among sympatric species—ocean sunfish Mola mola, bumphead sunfish Mola alexandrini, and sharptail sunfish Masturus lanceolatus—through stomach content and stable isotope analyses. A literature review revealed that the Family Molidae exhibits broader diets than previously characterized. Mola mola, M. alexandrini, and M. tecta consume prey from epi/mesopelagic environments, while M. lanceolatus and slender sunfish Ranzania laevis consume prey from both epi/mesopelagic environments and benthic habitats. No gelatinous prey was found in the stomachs of R. laevis. Off Taiwan, M. mola and M. alexandrini had similar and relatively narrow diet breadths, primarily feeding on scyphozoans, suggesting similar trophic niches. In contrast, M. lanceolatus displayed a broader diet, mainly consuming tunicates and augmenting their diet from epi- and mesopelagic, coastal, and benthic habitats. Dietary differences between M. lanceolatus and the other species might be linked to morphological differences such as gape size and eye length. Mola mola and M. alexandrini tend to have larger gapes and eyes and our diet analysis shows that they forage on larger sized prey and at greater depths. [ABSTRACT FROM AUTHOR]

Climate change influences the geographic distribution of species, especially rare and endangered species such as the Vietnamese Golden Cypress (Xanthocyparis vietnamensis). In this study, we determined the key factors influencing modelled distribution of the species, and assessed the influence of climate change on the distribution of the species using the maximum entropy algorithm (MaxEnt) model, occurrence data of the species and environmental variables (climate, topography, and soil conditions). Our results showed that the MaxEnt models were significantly superior to a random prediction (AUC > 0.9). Precipitation of warmest quarter (bio18), elevation, distance to karst areas, and isothermality (bio3) contributed significantly modelled distribution of the species. The predicted size of the current potential distribution is significantly larger than the known range in Vietnam (i.e. Ha Giang, Tuyen Quang, Bac Kan, and Cao Bang provinces). The species' suitable areas were predicted to reduced and shift toward higher elevations in two climate models (ACCESS1-0 and MPI-ESM-LR) under two selected climate change scenarios (medium-low greenhouse gas concentration (RCP 4.5) and high greenhouse gas concentration (RCP 8.5)) in 2050 and 2070. These findings will provide valuable references for managers and decision-makers for the conservation management of rare and threatened species in Vietnam. [ABSTRACT FROM AUTHOR]

Environmental characteristics act as limiting factors for the establishment and survival of organisms, and this holds particular significance for ectothermic. Grammostola vachoni is an endemic Argentinean tarantula that inhabits central mountainous grasslands. In this study, we model their potential distribution and assess thermal parameters and vulnerability indices in unstudied populations to understand the species' survival limits. The models to explain the geographic distribution of G. vachoni demonstrate a non-random pattern and robust predictive capabilities. The monthly variables in December, October, and March were the greatest influence. Respect to thermal parameters calculated throughout locomotor performance, the critical thermal limits were 4.9 °C and 51.1 °C, and the preferred temperatures were correlated whit optimal temperature. According the occurrence probability, the species has a low probability of persisting in extreme coldest and hottest environments. In a more temperate environment, the probability increases, mostly at temperatures of about 35 °C. The thermal performance breadth was 19.30, the thermal tolerance range was 46.1 °C and the inferior and superior limits of B80 were 18.9 °C and 37.1 °C. Grammostola vachoni show a better performance at higher temperatures, and a preference for higher temperatures than other ectotherms. The diverse microclimates provide by the heterogeneous nature of mountain grassland outcrops can act as a refuge. Implications for insect conservation: Our results show that grassland outcrops play a key role in maintaining the G. vachoni population, as these environments appear to be less affected in the future. Moreover, the species' locomotor performance could cope with future thermal shifts. [ABSTRACT FROM AUTHOR]

Reproductive patterns observed in organisms are direct outcomes of the interaction among parameters such as phylogeny, body size, and environmental characteristics. However, the action of these parameters is rarely observed in an integrated perspective in the literature. Here, we collected 109 specimens of two congeneric species of treefrogs living in the same microhabitat (bromeligenous species of genus Ololygon) to compare the reproductive patterns of the two species, evaluating the effect of different parameters on the reproductive ecology of the organisms. Our results show that morphometric measurements between females of the two species were not significantly different, indicating similar body sizes. The species exhibited different degrees of sexual dimorphism, and interspecifically, females showed significant differences in breeding traits, with the species O. perpusilla demonstrating higher reproductive effort, characterized by increased ovarian mass and increased average egg size compared to O. littorea. We observed that differences in reproductive effort were strongly associated with egg size, which drove higher reproductive investment in O. perpusilla females. We conclude that although the species share many traits commonly related to the degree of reproductive investment, other drivers, not yet completely understood, may influence the reproductive aspects of organisms, generating unexpected patterns. [ABSTRACT FROM AUTHOR]

Although Antarctica is the most isolated continent on Earth, its remote location does not protect it from the impacts of human activities. Antarctic metazoans such as filter-feeding invertebrates are a crucial component of the Antarctic benthos. They play a key role in the benthic-pelagic carbon flux in coastal areas by filtering particles and planktonic organisms from the sediment–water interface. Due to their peculiar ecological niche, these organisms can be considered a wasp-waist in the ecosystem, making them highly sensitive to marine pollution. Recently, anthropogenic particles such as micro-nanoplastics and manufactured nanoparticles (MNP) have been classified as contaminants of emerging concern (CEC) due to their small size range, which also overlaps with the preferred particle size ingested by aquatic metazoans. Indeed, it has been demonstrated that some species such as Antarctic krill can ingest, transform, and release MNPs, making them newly bioavailable for other Antarctic filter-feeding organisms. Similarly, the production and use of anthropogenic MNP are rapidly increasing, leading to a growing presence of materials, such as nano-sized metal-oxides, in the environment. For these reasons, it is important to provide evidence of the adverse effects of such emerging contaminants at sub-lethal concentrations in environmental risk assessments. These contaminants may cause cascade effects with consequences not only on individuals but also at the community and ecosystem levels. In this review, we discuss the state-of-the-art knowledge on the physiological and molecular effects of anthropogenic MNP in Antarctic aquatic metazoans. We further highlight the importance of identifying early biomarkers using sessile metazoans as sentinels of environmental health. [ABSTRACT FROM AUTHOR]

The dynamic interplay between anthropogenic activities and biodiversity conservation necessitates a nuanced understanding of habitat change, especially in contexts marked by transitions from grasslands to forested areas. This investigation utilised three threatened butterfly species—the Marsh Fritillary, Apollo, and Large Blue—as models to explore how grassland associated species respond to altered environmental conditions. The methodology encompassed extensive field surveys and statistical analyses with ecological niche modelling to determine their current and future distributions on the Island of Gotland. The species were surveyed under distinct years from 2017 to 2020 in a total of 3333 hectares in a 6000 hectare area—the Marsh Fritillary in 2017 (1232 hectares), Apollo in 2019 (2346 hectares), and Large Blue in 2020 (2256 hectares). Results revealed that the estimated current extents of suitable habitats were 49,104 hectares for the Marsh Fritillary (15.6% of the island), 45,646 hectares for Apollo (14.5%), and 33,089 hectares for Large Blue (10.5%). In general, increased forest and shrub cover and decreased heterogeneity negatively affected butterfly occupancy, but each species exhibited unique habitat preferences. The predictive modelling demonstrated that continued succession would reduce the amount of habitats predicted to be suitable and generated alarming forecasts—a twofold increase in forest and shrub cover suggests habitat declines of 41%, 47%, and 65% for the Marsh Fritillary, Apollo, and Large Blue, respectively. Given these findings, proactive measures are imperative for strategically managing these habitats to preserve landscape heterogeneity and accommodate diverse ecological needs. This study is important to conservation management providing, crucial insights amid anthropogenic and ecological changes. [ABSTRACT FROM AUTHOR]

With the increasing urban environmental problems, spontaneous vegetation has been gradually emphasized for high ecological value, whose distribution has been reported as strongly influenced by fine-scale environmental factors. As one of the major zones for urban spontaneous vegetation distribution, urban riparian corridors are well suited for research on the response of spontaneous plants to microhabitats. Taking the Wenyu River-North Canal in Beijing as the study site, we measured six microhabitat factors, including the level of maintenance and visitor activity, canopy density, litter thickness, and distance to water and road, to investigate their effects on spontaneous plant assemblages. The results showed that spontaneous plants respond significantly to fine-scale habitat variation, and were more responsive to human disturbance than other factors. Compared with diversity indicators, the functional trait compositions were more significantly correlated with microhabitat factors. Under lower maintenance of plants, the spontaneous communities had a higher invasion risk for plants. Thick litter can impede the occurrence of invasive species while favoring the growth of native ones. Our findings are important for furthering understanding of the spontaneous plant community establishment, and can serve as a good reference for the maintenance and management of spontaneous plants in urban riparian corridors. [ABSTRACT FROM AUTHOR]

Tyrannosaurids were the most derived group of Tyrannosauroidea and are characterized by having two body plans: gracile, long-snouted and robust, deep-snouted skulls. Both groups lived sympatrically in central Asia. Here, we report a new deep-snouted tyrannosaurid, Asiatyrannus xui gen. et sp. nov., from the Upper Cretaceous of Ganzhou City, southeastern China, which has produced the large-bodied and long-snouted Qianzhousaurus. Based on histological analysis, the holotype of Asiatyrannus xui is not a somatically mature adult, but it already passed through the most rapid growth stages. Asiatyrannus is a small to medium-sized tyrannosaurine, with a skull length of 47.5 cm and an estimated total body length of 3.5–4 m; or around half the size of Qianzhousaurus and other large-bodied tyrannosaurines in similar growth stages. Asiatyrannus and Qianzhousaurus are sympatric tyrannosaurid genera in the Maastrichtian of southeastern China. Asiatyrannus differs from Qianzhousaurus in that it has a proportionally deeper snout, longer premaxilla, deeper maxilla, and deeper dentary, and the cornual process of the lacrimal is inflated without developing a discrete horn. The different skull proportions and body sizes suggest that Asiatyrannus and Qianzhousaurus likely had different feeding strategies and occupied different ecological niches. [ABSTRACT FROM AUTHOR]

The present study aimed to assess mosquito species diversity, distribution, and ecological preferences in the Covè, Ouinhi, and Zangnanado communes, Southern Benin. Such information is critical to understand mosquito bio-ecology and to focus control efforts in high-risk areas for vector-borne diseases. Mosquito collections occurred quarterly in 60 clusters between June 2020 and April 2021, using human landing catches. In addition to the seasonal mosquito abundance, Shannon's diversity, Simpson, and Pielou's equitability indices were also evaluated to assess mosquito diversity. Ecological niche models were developed with MaxEnt using environmental variables to assess species distribution. Overall, mosquito density was higher in the wet season than in the dry season in all communes. A significantly higher Shannon's diversity index was also observed in the wet season than in the dry seasons in all communes (p < 0.05). Habitat suitability of An. gambiae s.s., An. coluzzii, Cx. quinquefasciatus and Ma. africana was highly influenced by slope, isothermality, site aspect, elevation, and precipitation seasonality in both wet and dry seasons. Overall, depending on the season, the ecological preferences of the four main mosquito species were variable across study communes. This emphasizes the impact of environmental conditions on mosquito species distribution. Moreover, mosquito populations were found to be more diverse in the wet season compared to the dry season. [ABSTRACT FROM AUTHOR]

Adaptation to different ecological niches is considered one of the main drivers of species diversification, also in cryptic species complexes, notwithstanding their morphological stasis. We here review all the published information on ecological differentiation within cryptic species complexes within the phylum Rotifera. We found 177 instances of cryptic species identified genetically, published in 101 papers. Only a subset of the papers contained available information on ecological differences and only for two of the 54 known complexes, namely Brachionus calyciflorus s.l. and Brachionus plicatilis s.l., sufficient data were available for analyses of ecological differences. For the B. calyciflorus complex, B. fernandoi consistently occurred at a significantly lower temperature than the other species in the complex; no differences were found for other environmental variables. For the B. plicatilis complex, B. paranguensis occurred in waters with higher pH than the other species; no differences were found for other environmental variables. These results, even if preliminary and based on scattered information, reveal that adaptation to different ecological niches exists also between closely related species. Our aim is to showcase this interesting field of research spurring further detailed studies to focus on the mechanisms of ecological speciation using rotifer cryptic species as a model system. [ABSTRACT FROM AUTHOR]

Benthic amphipod feeding groups are a well-established trophic classification that is mostly based on field observations and laboratory tests and are used in ecological studies to monitor the ecological state of benthic ecosystems. Globally, carbon and nitrogen stable isotope ratio investigations have provided confirmation of, and novel insights into, the trophic ecology of benthic animals, such as polychaetes. However, stable isotopic examinations of benthic amphipods have been limited. Here, we used microgram samples to compare the species-specific dietary sources, trophic positions, and isotopic niche overlap of selected benthic amphipods from the Gulf of Kachchh, Marine National Park, using elemental analyser-isotopic ratio mass spectrometry (EA-IRMS) of carbon and nitrogen. Overall, all primary carbon sources presented wide variation in the isotopic values of δ13C (6.3‰) and δ15N (greater than 13‰). Conversely, the amphipod taxa displayed relatively narrow range for δ13C (3.9‰) and wider range for δ15N (more than 10‰). The results of the Bayesian mixing model revealed that the benthic amphipods had species-specific feeding preferences. However, the predominant carbon source was organic matter in sediment which reinforced benthic pathways for energy flow for most species. According to the estimated trophic level values (1.62–3.39), these species play a significant role as primary and secondary consumers serving as crucial trophic intermediaries in the food chain, connecting the base to the top consumers. High overlapping ecological niche amongst species was detected by SIBER analysis which indicated co-existence of the benthic amphipods in their respective microhabitats. This signifies wider utilisation of resources and inter-specific feeding preferences with minimal competition amongst amphipod species. [ABSTRACT FROM AUTHOR]

Nest-site selection is a behavioral response that can provide protection for adults, eggs and nestlings, affecting fitness. Since predation is the main cause of nest loss worldwide, it has been considered as the main evolutionary driver in nest-site selection. Nevertheless, in some cases, nest microclimate may be the primary evolutionary force operating on nest-site selection. We aimed at determining at mesohabitat and microhabitat scales if Chilean Elaenia (Elaenia chilensis) selected the nest site and, if so, whether such selection was associated with a reduction in nest predation. Since nest orientation may influence nest microclimate, we also tested whether it affected the reproductive output. At the mesohabitat scale, the subcanopy cover (1.5–4 m from the ground) was selected by this species. At the microhabitat scale, elaenias preferred Schinus patagonicus to nest and oriented their nests preferentially to the north and eastern directions. These selected habitat features had no effect on nest success and reproductive output. Despite the risk of nest predation by several aerial (birds) and ground predators (rodents), both successful and predated Chilean Elaenia nests were close to the ground rather than at intermediate heights. Considering the hardness of S. patagonicus wood that can provide structural support to the nest against strong winds, and that nests were oriented to the opposite direction of prevailing wind, Chilean Elaenia nest-site selection might be related to microclimatic factors at nest sites rather than predation. Therefore, it is imperative to consider potential associations between nest microclimate and habitat features to advance in the understanding of bird nest-site selection. [ABSTRACT FROM AUTHOR]

To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province, East China, the main stream and the Shanxi-Zhaoshandu Reservoir in the downstream were chosen as the study area, for which 22 sampling sites were designated. Sampling was conducted in September 2021, January, May, and July 2022. Phytoplankton species were identified from both quantitative samples and in-vivo observations. Phytoplankton was quantified by direct counting. Results show that there were 98 species belonging to 6 phyla and 78 genera. In addition, to clarify the niches of the dominant phytoplankton species and their interspecific association, the dominance index was calculated, and a comprehensive analysis was conducted including niche width, niche overlap value, ecological response rate, overall association, chi-square test, and the stability. The phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community, showing higher diversity in spring and lower diversity in summer. Among 11 dominants phytoplankton species from 3 phyla, both frequency and dominance degree varied seasonally, of which Microcystis sp. was the dominant species in Spring, Autumn, and Winter. The niche widths of the dominant species ranged from 0.234 to 0.933, and were categorized into three groups. The niche overlap values of the 11 dominant species ranged from 0.359 to 0.959, exhibiting significant seasonal differences—highest in winter followed by autumn, spring, and summer in turn. The overall correlation among dominant species in all four seasons revealed a non-significant negative association, resulting in an unstable community structure. A significant portion (84.2%) of species pairs displayed positive associations, suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and space. Despite this pattern, stability measurements indicated that the dominant species community remained unstable. Therefore, careful monitoring is recommended for potential water environment issues arising from abnormal proliferation of dominant species in the watershed during winter. This research built a theoretical foundation with a data support to the early warning of eutrophication and provided a reference for water resources management in similar watersheds along the eastern coast of China. [ABSTRACT FROM AUTHOR]

Thermal and microhabitat resources are two fundamental requirements that affect the life history of any ectotherm. Furthering our understanding of how reptilian species meet these ecological requirements is crucial for assessing the impact of environmental and anthropogenic changes on populations. Here, we explored some fundamental aspects of the thermal and microhabitat ecology of Conopsis biserialis, a small, burrowing, and endemic earthsnake of central Mexico. The study was conducted during the rainy season in a montane site disturbed by rural activities. The mean field body temperature (Tb) of C. biserialis was 26 ± 0.6 ºC. Field Tb did not differ significantly between sex and development stages. However, we found that Tb was positively correlated with substrate, air, and under-rock temperatures (Ts, Ta, and Tr) in the rural microhabitat. Regression analysis showed that substrate and under-rock temperatures (Ts and Tr) were the parameters that best explained Tb variability in the individuals. The temperature and relative humidity under shelter did not differ significantly among shelter types and/or rock sizes. In addition to these thermal traits, earthsnakes selected and utilized six common biotic and physical elements of the rural microhabitat. Most individuals used high proportions of large and medium rocks for sheltering, and these rocks were selected around crop fences and cleared grasslands where the soil can be either covered with low vegetation or bare. Our results suggest that, during the rainy season, individuals of C. biserialis use and select some biotic and structural resources of the rural microhabitats, and were capable of actively regulating their temperature by using shelters with high values of microclimatic homogeneity. [ABSTRACT FROM AUTHOR]

This article explores the use of low-flying drones to map substrate compositions in coral reefs and study the microhabitat use of coral reef fish. The study found that drones were effective in describing substrate composition, locating target fish in microhabitat mosaics, and recording their behaviors. However, the study also acknowledges the challenges of using drone photography, such as weather and sun conditions. The author suggests that low-flying drone photography should be applied to study fish in shallow and clear waters. [Extracted from the article]

Predator–prey interactions drive the evolution of prey visual camouflage, but prey species also must remain conspicuous to their conspecifics for social signaling purposes. Whether rapid body color change can help to balance conspecific visibility and predator concealment, in the eyes of each group's respective visual systems, remains poorly understood. We tested this question using water anoles (Anolis aquaticus), a small lizard that uses rapid dark-to-light body color change to visually camouflage itself from its avian predators across diverse microhabitats. We used digital image analysis and visual modeling to assess the effectiveness of color-matching camouflage in dark- and light-phase A. aquaticus, as perceived by anoles and avian predators. Our findings reveal that A. aquaticus body coloration was perceived similarly by both groups. However, sex-specific differences in overall conspicuousness emerged, with males more consistently color matching their microhabitats compared to females. Females were less likely to color match their backgrounds in their lighter phase, suggesting a sex difference in preferred conspicuity in more exposed habitats. We highlight the context-dependence of color change, with sex-specific differences and microhabitat potentially affecting its function. Significance statement: Predator and prey visual systems influence prey species' visual camouflage evolution, but whether rapid body color changes allow animals to dynamically balance conspecific visibility with predator concealment is not well known. We used visual modeling techniques to examine if water anoles (Anolis aquaticus), small lizards that employ rapid body color changes to evade their avian predators, appear differently to their predators and conspecifics depending on color phase. Our findings reveal that A. aquaticus body coloration is perceived similarly by both groups. However, we observed sex-specific differences: males and larger individuals displayed more consistent color matching across different microhabitats, whereas females showed reduced matching in their lighter phase. Our study underscores the context-dependence of the function of color change in relation to factors including sex and microhabitat. [ABSTRACT FROM AUTHOR]