Species' habitat utilization reflects their habitat preferences and activity patterns. Understanding the coexistence mechanism of wild ungulates is critical for deciphering intra- and inter- species survival strategies. The interactions between species including predation, competition, symbiosis, and reproduction, are dynamic processes influenced by seasonal shifts, diel cycles, and weather variations. The Baotianman National Nature Reserve in northern China hosts diverse wild ungulate populations, yet their daily activity rhythms remain inadequately investigated. Leveraging camera-trap data, we investigated the seasonal daily activity patterns of five sympatric wild ungulates (i.e., forest musk deer Moschus berezovskii, Siberian roe deer Capreolus pygargus, Reeve's muntjac Muntiacus reevesi, wild boar Sus scrofa, Chinese goral Naemorhedus griseus), to assess temporal niche differentiation as a key coexistence mechanism. Comparative analyses revealed statistically significant seasonal differentiation in daily rhythms among these species. By Watson's U 2 test, the daily activity patterns differed significantly across forest musk deer, Reeve's muntjac, wild boar, and Chinese goral (p < 0.05). In contrast, the activity rhythms showed no significant differentiation between forest musk deer and Siberian roe deer. Notably, we found that forest musk deer, Siberian roe deer, and Reeve's muntjac were crepuscular, whereas wild boar and Chinese goral were diurnal. The highest degree of overlap coefficients was observed between the forest musk deer and the Siberian roe deer, with no significant difference in their diel activity rhythms. This study offers novel insights for developing conservation strategies for wild ungulates, and is crucial for maintaining ecological balance and biodiversity.

Mechanisms of coexistence between Scomber australasicus and Scomber japonicus from the perspective of feeding ecology.

Elusive encounters: Activity patterns of the threatened Western polecat and niche overlap with co-occurring carnivores.

Since the early 2000's, Modern Coexistence Theory (MCT) has guided empirical investigations of coexistence. We reviewed empirical applications of MCT to answer two questions: (1) What have we learned about the strength of temporal, spatial and variation-independent mechanisms of coexistence in nature? (2) How have studies of niche and fitness differences advanced our understanding of coexistence? With respect to the first question, we now have evidence that the temporal storage effect and variation-independent mechanisms help stabilize coexistence in many systems. We have not learned more due to the low number of tests of these mechanisms (24 out of 84 MCT studies), the narrow focus on mechanisms involving temporal variation and grassland communities, and lack of rigorous model validation. With respect to our second question, studies of niche and fitness differences (61 of 84 studies) have answered fundamental questions about the role of phylogenetic relatedness, plant-soil feedbacks, and functional traits in coexistence. We recommend that future empirical MCT studies (1) match hypotheses to MCT quantities, (2) address gaps in empirical studies, (3) avoid known biases in estimating competition coefficients, and (4) validate models with independent data.

The degradation and utilization of lignocellulose are pivotal for understanding the competitive dynamics and coexistence mechanisms underpinning complex invasions by wood-boring beetles. Despite the broad repertoire of lignocellulolytic enzymes in these insects and their gut microbiota, the collaborative mechanisms of lignocellulose breakdown remain poorly understood. In the context of a multi-species beetle invasion system, we investigated the lignocellulose degradation processes of two major pests of Pinus massoniana, Monochamus alternatus and Orthotomicus erosus, using a combination of lignocellulase activity assays, multi-omics analyses, and two-dimensional nuclear magnetic resonance (2D-NMR). Our findings revealed that the two major pests of P. massoniana exhibit distinct lignocellulose degradation strategies driven by host enzymatic specialization: M. alternatus excels in cellulose hydrolysis via robust endogenous endoglucanases, whereas O. erosus prioritizes hemicellulose breakdown. Although the gut microbiota of both species assist terminal hydrolysis by compensating for low β-glucosidase activity and partially modifying lignin via selective β-O-4 bond cleavage, host enzyme divergence underpins their primary niche differentiation. The gut microbial composition further refines nutrient partitioning, enabling coexistence. This study unveils a dual lignocellulose degradation strategy in pine-boring beetles, integrating host enzymatic specialization and microbiome-mediated bond cleavage, which provides new insights into forest pest control and sustainable biomass utilization. © 2026 Society of Chemical Industry.

How do herbaceous plant species coexist in the diverse communities of the arid ecosystems of the world? We review understanding for southwestern North America where these communities are threatened by invasive species and climate change. Relative abundances of these species fluctuate from year to year due to their different regeneration niches (germination and growth requirements), which are sensitive to environmental fluctuations. Such regeneration niche differences were an early hypothesis, with much support, for how these species coexist. Seed predation provides other coexistence mechanisms supported by empirical studies. Indeed, dramatic effects of seed predators on community dynamics have been observed through the controls they impose on invasive plant species. Various studies have included measurements of frequency-dependent predation whereby seed predators shift their preferences to the most abundant species as densities change, and predator partitioning, where the different prey species have different patterns of susceptibility to the various predator species. Due to insufficient studies of predator partitioning, we conducted proof-of-concept experiments on seed predation by ants in an herbaceous plant community in the Sonoran Desert. We show that various ant species discriminate differently between the various plant species, meaning that the plant species have different seed-predation niches, potentially contributing to their coexistence. More extensive studies are needed to assess the roles of seed predators in maintaining the diversity of these plant communities. Deficient also, are studies of density feedback that measure how much a specific mechanism promotes recovery of a species from low density, and allows that species to coexist with other members of the plant community. Failure to assess such density feedback empirically in coexistence studies is pervasive and weakens empirical claims for most mechanisms of species coexistence. Key advances can be made by developing and implementing methods to link density feedback to proposed mechanisms in the field.

ABSTRACT The Nine Cities of Ili in the Qing Dynasty formed a frontier urban system that integrated military defense, administration, agriculture, and trade in the Ili River Valley. Existing studies have mainly focused on individual cities or historical events, with limited attention to the spatial logic of the system as a whole. This study examines the Nine Cities of Ili as an integrated regional network and explores how physical geography, military-political strategy, and socio-economic dynamics jointly shaped their distribution and functions. Using historical documents, field investigation, and GIS-based spatial analysis, we constructed a spatiotemporal database to analyze city siting, inter-city relations, and functional organization. The results show that the system was shaped by the interaction of environmental constraints, strategic node selection, and functional complementarity, forming a hierarchical pattern centered on Huiyuan City. The study contributes to research on frontier urbanism and offers historical insight for border-region planning and heritage-network conservation.

Understanding how ecologically similar species coexist remains a central question in ecology. Shifts in species composition along environmental gradients offer opportunities to explore underlying mechanisms, such as condition-specific competition-where competitive dominance reverses across environments. However, broad-scale gradients often involve multiple co-varying abiotic factors, making causal inference difficult, and experimental evidence for competition reversal remains limited. Although temperature is widely regarded as a key driver of salmonid distributions, its mechanistic role remains unclear. We investigated the roles of temperature and species interactions for the coexistence of juvenile Dolly Varden (Salvelinus curilus, colder-adapted) and white-spotted charr (S. leucomaenis, warmer-adapted) in multiple replicated tributaries that minimized spatial-autocorrelation and co-varying physiochemical factors. Structural equation modeling revealed that water temperature significantly influenced Dolly Varden density but not that of white-spotted charr. In addition, Dolly Varden density negatively affected white-spotted charr density, while the reverse effect was not detected, contradicting prior findings of white-spotted charr competitive dominance. A transplant experiment showed that white-spotted charr persisted and grew well in cold tributaries where Dolly Varden numerically dominated. These results suggest that white-spotted charr avoid cold habitats not due to thermal limitations, but due to biotic interactions with Dolly Varden, potentially mediated by food availability. Thus, although temperature shapes species distributions, temperature-specific competition reversal is unlikely to be the dominant mechanism. Because Dolly Varden typically establish themselves in these habitats earlier and attain numerical dominance, we propose that prior residence effects-where early occupants gain competitive advantages-may better explain local coexistence patterns in this system.

Abstract The Sasa-Satsuma equation, an integrable extension of the nonlinear Schr"odinger equation, could provide a more accurate description of ultrashort optical pulse propagation by incorporating third-order dispersion, self-steepening, and delayed nonlinear response. In this work, we establish a quantitative correspondence between the spectral degeneracies of two types of related linear non-Hermitian matrixes and the localized wave solutions of the nonlinear Hermitian systems. Compared with the standard nonlinear Schr"odinger equation system, the Sasa-Satsuma equation displays richer spectral and dynamical structures due to its multi-band Hamiltonian. In particular, we show that exceptional points correspond to rogue waves in the modulational instability regime and to W-shaped solitons in the modulational stability regime. Moreover, higher-order degeneracies, such as third-order exceptional points, reside at the boundary between modulational stability and modulational instability. This configuration enables a coexistence mechanism of W-shaped solitons and rogue waves, where two W-shaped solitons can interact to generate a rogue wave. These results provide a unified non-Hermitian perspective on localized wave phenomena in higher-order integrable systems and reveal the fundamental link between spectral degeneracies and nonlinear wave dynamics.

In situ electrochemical impedance spectroscopy monitoring of high-temperature intercalation and conversion coexistence mechanisms in Nb14W3O44 cathode materials for high-capacity thermal batteries.

The storage effect is a general explanation for ecological coexistence, wherein different species specialise on different states of a fluctuating environment, for example, hot versus cold years. Despite the storage effect's prominence in theoretical ecology, we lack evidence on whether it maintains biodiversity in nature. Here, we examine five storage effect pathways in a community of 11 coral species from the Great Barrier Reef, using detailed size-structured demographic data collected over 5 years. We parameterize integral projection models, simulate coral communities, and quantify coexistence mechanisms through Modern Coexistence Theory. Fluctuations in survival and fecundity promote coexistence via the storage effect, but this stabilising mechanism is typically small compared to fitness differences. Despite exhibiting prerequisites for strong temporal niche partitioning, the storage effect cannot explain the coexistence of many species. Diversity maintenance likely requires large net contributions from other mechanisms, such as specialist natural enemies or spatial heterogeneity coupled with source-sink dynamics.

Seasonal dynamics and coexistence mechanisms of plankton communities in a Karst Plateau reservoir: Integrating network analysis and environmental drivers

This article introduces the concept of "blurring-boundary" to illustrate the ways Nestorianism adopted in Tang Dynasty to secure legal recognition and to conduct its localization within Chinese society. Through an analysis of the Nestorian Stele and the Zhixuan Anle Sutra, this paper demonstrates how Nestorianism expressed Christian doctrine by drawing on the linguistic structures and cosmological terms of Buddhism and Taoism, thereby gaining acceptance in the ideological system within Tang China. Unlike Buddhism's broad popular base and Islam's community-based mode for communication, Nestorianism adopted elite-targeted communication strategies aimed at the imperial and scholar-officialdom, emphasizing political obedience, metaphysical compatibility, and linguistic adaptation in its attempt to participate in the royal network dominated by Buddhism. Through comparative religious and political discourse analysis, this paper highlights a distinctly "non-confrontational" mode of religious adaptation that offers a new perspective on the mechanism of coexistence within dominant cultural systems.While this paper mainly focuses on textual strategies rather than practical networks, it aims to provide theoretical reference for future research on religious transmission and cultural boundary.

Modern Coexistence Theory (MCT) has long aimed to predict community structure, but empirical support remains scattered across unconnected case-studies from a narrow subset of systems where it is possible to quantify niche and fitness differences (e.g., pairwise interactions between fast-growing plants or protists). We sought a framework to apply MCT to a broader range of ecological scenarios by combining eDNA dietary data with life-history traits of mammal herbivores from diverse communities across three African savannas. Although this first application of the framework treated dietary niche differentiation as the sole mechanism for coexistence, it unveiled three conclusions about multispecies coexistence. First, dietary niche differentiation promoted coexistence but was insufficient to explain observed coexistence for all species. Second, modelled coexistence patterns in herbivore communities could not be predicted from species-level traits or pairwise comparisons. Third, herbivore diversity is generally robust to reductions in the number of plant resources, particularly when there is more dietary specialisation.

This study aimed to examine and compare the breeding biology of two sympatric woodpecker species, Picus canus and Dendrocopos major , in the midwestern region of South Korea, with the goal of elucidating interspecific differences in breeding strategies among closely related taxa. From 2018 to 2021, a total of 106 breeding nests (57 belonging to P. canus and 49 to D. major ) were identified within forested areas of Seocheon and Gunsan. Data were collected on the species of nest trees and their structural characteristics, alongside breeding parameters such as egg-laying date, clutch size, period of incubation and nestling, and rates of hatching and fledging success. Observations were conducted through external nest monitoring supplemented by internal inspections using an endoscopic camera. Both species primarily selected Paulownia coreana , Prunus sargentii , and Castanea crenata as nesting cavities; however, P. canus preferred nest trees with greater height and diameter at breast height compared to those chosen by D. major . The mean egg-laying date for D. major occurred approximately two weeks earlier than that of P. canus , while clutch size and incubation period were significantly larger and longer, respectively, in P. canus . In contrast, no significant interspecific differences were detected in nestling period or in hatching and fledging success rates. This suggests that a larger clutch size does not necessarily lead to higher breeding success under similar nesting conditions. These results indicate that sympatric woodpecker species may share overlapping nesting resources yet exhibit distinct species-specific differences in nest tree structural selection, and breeding traits. This study provides foundational insights into the breeding biology of woodpeckers inhabiting temperate East Asian forests and advances understanding of breeding strategies and coexistence mechanisms among cavity-nesting avian species.

Understanding the mechanisms by which competing species coexist is fundamental for explaining the distribution and abundance of organisms. Many coexistence mechanisms require trade-offs in the ability to deplete shared resources, but resource depletion by competing species is rarely measured, especially in communities of mobile predators. Among competing predators, differences in diet and habitat use are commonly observed, and to promote coexistence, these differences must be associated with trade-offs in the ability to suppress different prey types (prey partitioning) or to suppress prey in different habitats (spatial differences in competitive ability), respectively. We hypothesize that these two mechanisms are important for competition among three arboreal lizards common in Hawaii. We test these mechanisms using experimental monocultures to measure prey suppression and a consumer-resource model parameterized with trait and demographic data from the same experiment. We found that species differed in spatial patterns of prey suppression, supporting spatial differences in competitive ability, but species did not differ in which prey taxa they suppressed, providing no support for prey partitioning. Patterns of prey suppression were consistent with differences between species in microhabitat-specific attack rates, and including differences in the conversion of prey into offspring allowed model outcomes to better align with species' relative prey suppression. When using the model to predict competitive outcomes, Phelsuma laticauda and Anolis sagrei are expected to coexist over a wide range of microhabitat availabilities, Anolis carolinensis can coexist with P. laticauda under a wider range of microhabitat availabilities than it can with A. sagrei, and A. carolinensis cannot persist in the presence of both of the other species under any conditions. These predictions are consistent with the change in community composition that has occurred over time in the field: Anolis carolinensis has declined while the other two species have increased in distribution and abundance. Our results also demonstrate that differences in diet do not necessarily translate into resource partitioning of prey, highlighting the importance of measuring resource depletion when understanding exploitation competition.

Understanding interactions among sympatric mesocarnivore populations is essential for making sound management decisions. The golden jackal has rapidly expanded in Europe, raising questions about its potential intraguild effects. Using long-term hunting bag data (1997-2024) from Hungary, we investigated spatiotemporal population trends of the European badger, red fox, and golden jackal. We examined pairwise associations in their annual growth rates. Generalised additive models and Pearson correlation analyses revealed strong species-specific temporal and spatial trends and weak to moderate positive relationships among the species' population growth rates at the national scale and within regions of high jackal population density. We found no evidence of jackal suppression of foxes or badgers. Additionally, badgers showed the strongest positive association with fox populations. Our large-scale analyses suggest that these mesocarnivores coexist without substantial competitive interference, likely due to local spatial heterogeneity and fine-scale temporal partitioning that are not detectable in annual, broad-scale (national) data. These findings highlight the importance of integrating broad-scale population data with finer-scale behavioural studies to better understand coexistence mechanisms in expanding mesocarnivore assemblages.

Spatiotemporal dynamics of actinomycetes in a brackish lake: Environmental drivers and coexistence mechanisms

Free radical mechanisms of halogen coexistence promoting pollutants formation.

ABSTRACTUnderstanding the mechanisms of species coexistence is a long‐standing goal in community ecology. The performance of woody seedlings across different ecological niches has been proposed as a key mechanism in community assembly. Factors influencing seedling survival can be revealed by analyzing neighboring plants in conjunction with their phylogenetic relatedness, functional traits, and the surrounding environment. In the present study, we conducted a seasonal analysis of 936 seedlings for 56 species from a 4‐ha subtropical forest over 3 years in the Gaoligong Mountains, Southwest China. Our aims were to examine the relative effects of neighbor density, habitat conditions, and seasonal climate variability on seedling survival during dry and rainy seasons, and to determine whether the sensitivity of seedling survival responding to neighbor densities and abiotic factors differs between seasons. The findings indicated that the relative importance of neighbor densities, habitat factors as well as seasonal rainfall on seedling survival varied with seasonality. During the rainy season, seedling survival was comparatively less affected by conspecific neighbor density and was mainly negatively influenced by rainfall, whereas habitat factors (including topography, soil properties, and canopy openness) were detrimental for survival to a lesser extent. There is evidence suggesting that phylogenetic negative density dependence (PNDD) and functional negative density dependence (FNDD) are more pronounced in the rainy season. In contrast, the positive effect of canopy openness was more important during the dry season. Our findings further revealed that the effects of PNDD, FNDD, canopy openness, and seasonal rainfall varied widely among species across seasons. Moreover, species differed in their ability to respond to the trade‐offs between canopy openness and rainfall in relation to phylogenetic relatedness and functional dissimilarity during the dry and rainy seasons. Overall, our results demonstrate that seasonality modulates the strength and importance of phylogenetic and functional density dependence, habitat preference, and climate for seedling survival in subtropical forests. The seasonal variations in these effects allow species to maintain coexistence across dry and rainy seasons. Consequently, seasonal variability should be accounted for in future studies in understanding the diversity of forest communities.