Ecology and Evolution最新文献

Sexual dimorphism in lizards arises from the dynamic interplay between natural and sexual selection, manifesting in divergent phenotypic traits across taxa. A key unresolved question is whether the relationship between such sexually dimorphic traits and functional performance also differs between the sexes. This study investigated this question in the mountain dragon (Diploderma vela), a protected species endemic to the upper Lancang River basin in southwestern China, by quantifying its sexual dimorphism in morphology and coloration and assessing their sex-specific correlations with bite force. A total of 94 individuals were assessed for nine morphological traits, maximum bite force capacity, and body coloration across 15 anatomical regions. After controlling for body size, significant male-biased dimorphism was detected in most morphological traits, whereas abdomen length was female-biased. Coloration also differed between sexes across all measured regions except the abdomen. Crucially, the relationship between morphology and bite force was sex-specific; different suites of traits predicted bite force in males versus females. In contrast, no correlation was found between coloration and bite force in either sex. These divergences reflect the species' flexible phenotypic responses to varying reproductive and ecological pressures. These findings demonstrate that sexual dimorphism extends beyond trait means to encompass sex-specific phenotype-performance relationships, highlighting differential adaptive responses. This work provides a functional framework for understanding trait evolution in D. vela and underscores the need for sex-specific considerations in its conservation.

Movement is a fundamental process in structuring communities, distributing species, and mediating gene flow. Both extrinsic (e.g., density of species) and intrinsic factors (e.g., body size) influence movement patterns, ultimately driving the spatial organization of ecological communities. However, these extrinsic and intrinsic factors are often assessed in isolation, limiting our ability to understand how multiple factors combine to shape movement patterns in nature. Here, we evaluate whether body size (intrinsic) and intra- and interspecific densities (extrinsic) have an impact on the movement rates of four fish species (Nocomis leptocephalus bluehead chub, Semotilus atromaculatus creek chub, Lepomis cyanellus green sunfish, and L. auritus redbreast sunfish) in a small stream. We employed a capture-mark-recapture framework to individually track movements, defined as the difference between locations on consecutive (re)captures. We then applied a dispersal-observation model that accounts for detectability, survival, and emigration when inferring movement processes. We found that larger individuals of creek chub and green sunfish were more likely to move, which may be explained by their greater physical ability to balance the energetic cost of moving in tandem with greater competitive ability during settlement. The effect of density on movement was mixed. Green sunfish moved away from areas with high density of creek chub, but movement declined when bluehead chub density was high. Bluehead chub responded reciprocally to green sunfish, with less movement at high green sunfish density. Movement also declined for creek chubs in the presence of bluehead chub. This may suggest that certain species interact due to predator–prey interactions either directly or indirectly. Collectively, our results suggest that intrinsic (body size) and extrinsic factors (density) influence movement patterns, but their relative importance is species-specific. Further exploring the mechanistic relationship behind drivers of movement will provide greater insights into spatial community dynamics.

Climate change-induced grassland degradation has exacerbated the spread of toxic plants, yet many potentially toxic species remain overlooked, undermining rangeland management and causing significant economic losses. Quantifying the toxicity and distribution of potential toxic plants under climate change is critical for mitigating biogeographic risks. As a case study, taking Sphaerophysa salsula, a leguminous plant distributed in Asia and the Americas, historically utilized for erosion control but recently associated with livestock poisoning, this research integrated toxicity identification, species distribution modeling (SDM), and risk assessment to evaluate its biogeographic threats in China. Results suggested for the first time that S. salsula can function as a high-toxicity (chemotype 1) locoweed due to swainsonine (mean content 0.373%), produced by its endophyte Alternaria oxytropis (23.46 pg/ng), which is implicated in locoism-like syndromes in livestock. The Maximum Entropy model identified temperature annual range (43.22°C), mean temperature of the driest quarter (−6.29°C), and soil pH (8.61) as key distribution drivers. Currently, suitable habitats are concentrated in Northern China (Xinjiang, Inner Mongolia, Ningxia). By the 2070s, these habitats are projected to decline by 6.3%–9%, shifting westward toward pastoral regions. Risk assessments integrating grazing intensity revealed high-risk zones in Gansu, Ningxia, and Inner Mongolia, with future scenarios predicting declining risks in eastern Inner Mongolia but increasing threats in western Tibet. These findings clarify S. salsula's toxic mechanism and biogeographic risks, providing a framework for targeted management of overlooked toxic plants under climate change.

Local fish diversity in lakes has severely declined in the last century under the effects of climate change and human activities. Thus, examining the underlying factors and implementing appropriate measures are crucial for preventing further aquatic biodiversity losses. Environmental DNA (eDNA) metabarcoding represents a promising tool for improving fish population monitoring. While spatiotemporal variations of fish eDNA in lentic ecosystems have become a research focus, effective monitoring techniques remain limited. Therefore, this study used eDNA metabarcoding to monitor the diversity and spatiotemporal distribution of fish in Erhai Lake, China. Water samples from the shore, nearshore, and midline were collected from 2020 to 2021 during summer and autumn. Thirty-six taxa, including 5 native (one endangered species, Schizothorax taliensis) and 31 non-native taxa, were detected. Seasonal and spatial differences in fish community structure were observed. The seasonal distribution was primarily influenced by water temperature and nutrient status, while the spatial distribution was affected by water depth. Most fish species found in the lake were detected in shoreline samples, suggesting that shoreline sampling is a cost-effective strategy for monitoring fish diversity. These findings confirmed that fine-scale spatial sampling and eDNA metabarcoding represent effective tools for monitoring fish diversity and spatiotemporal distribution in lakes.

The endemic Sri Lankan leopard is the island's apex predator, living both within and outside protected areas. In unprotected, shared landscapes, it is important to understand leopard diet and predation patterns to foster long-term human–leopard coexistence. This study examines the diet of leopards in the human-dominated tea estate landscape of the Upper Kelani River Basin, in Sri Lanka's Central Highlands. Study goals were to evaluate prey composition, diversity, importance and selection, and to investigate the role of domestic species in leopard diet here. Analysis of 107 leopard scat samples showed leopard feeding behavior was best characterized as generalist and opportunistic, with a wide-ranging diet (H′ = 2.89) consisting of 17 evenly consumed (D = 0.94) prey species. While the diminutive black-naped hare (2.5 kg) was most available and most frequently detected in the diet (19.8% of samples), the importance of medium-sized prey was highlighted, with barking deer (25.5 kg) well utilized (13.9% of samples), representing > 20% of total biomass consumed and showing positive selection (0.281). Moderate selectivity was observed for sambar (0.410), the system's largest potential prey (160–215 kg), which may be expected for meso-carnivores in the absence of dominant intraguild competition. Primates are a key resource here (23% of samples and biomass) despite being uncommon in tea estates, suggesting preference by leopards. Targeted research to quantify primate abundance and selection is recommended. Overall, wild species represented > 85% of leopard diet, suggesting the landscape retains a substantial natural prey base. Domestic dogs, though common and widely perceived as targeted by leopards here, were moderately avoided (−0.378), a positive outcome for human–leopard coexistence. These findings highlight the leopards' generalist predation tendencies, while suggesting additional complexity and signaling selectivity in predation patterns. Results underscore the necessity of preserving wild prey abundance and diversity to facilitate coexistence in anthropogenically transformed environments.

Dixson, D. L., G. P. Jones, P. L. Munday, et al., “Terrestrial Chemical Cues Help Coral Reef Fish Larvae Locate Settlement Habitat Surrounding Islands.” Ecology and Evolution 1, no. 4 (2011): 586–595. https://doi.org/10.1002/ece3.53.

A mistake was identified in the calculation of the standard errors in Table 1. The errors do not affect the overall results or conclusions. The corrected version of the table is below:

The authors apologize for this error.

Feral horses (Equus ferus caballus) have established large populations in west-central British Columbia (BC), Canada, where they overlap with native ungulates, including a declining woodland caribou (Rangifer tarandus caribou) herd. In addition, feral horses co-occur with large carnivore species including wolf (Canis lupus) and cougar (Puma concolor). Feral horses may act as a resource subsidy for predators, potentially altering predator–prey dynamics, yet empirical observations of predator interactions with feral horses are scarce in Canada. Between 2019 and 2025, we documented 21 instances of wolf predation or scavenging of feral horses, including one direct observation of wolves actively hunting feral horses. We also documented 58 instances of confirmed feral horse predation by GPS-collared cougars. To the best of our knowledge, these are the first published observations of wolves hunting feral horses, and the first records of cougar predation of feral horses in British Columbia. Our findings suggest that feral horses may increase food availability for these two large carnivore species, potentially facilitating elevated predation pressure on native ungulate populations via apparent competition. These novel interactions underscore the complex and far-reaching ecological consequences of feral species. Further, they highlight the importance of incorporating non-native prey subsidies into predator–prey management frameworks.

Interactions between co-occurring pathogens can have complex and significant impacts on host survival, fitness, and population dynamics. While common in wildlife, coinfections are often overlooked, and research may create biased management perspectives when individual pathogens are assessed in isolation. Recent work has found that wild turkeys (Meleagris gallopavo) are affected by various pathogens, but it is unknown how infections and coinfections are spatially structured or interact with each other. Here, we determined the associations and risk factors of infection by lymphoproliferative disease virus (LPDV), reticuloendotheliosis virus (REV), three avian Mycoplasma species, and internal parasites in Pennsylvania wild turkeys. Our results indicate varying prevalences: LPDV (70%), REV (1%), Mycoplasma gallisepticum (0%), Mycoplasma meleagridis (4%), Mycoplasma synoviae (2%), and internal parasites (63%). The prevalence of LPDV was greater in adults than juveniles but did not vary with year, sex, study area, or landscape type. Parasite species richness was greater in juveniles than adults, greater in males than females, varied by year and study area, but did not vary with landscape type. Coinfections with LPDV and parasites were more common (41%) than infections with only LPDV (26%) or only parasites (22%). All other coinfection prevalences involving viruses, Mycoplasma species, and parasites were low (0%–3%). Finally, infection with LPDV did not differ with overall parasite species richness but was negatively associated with infection with parasitic nematodes. These results reveal high rates of coinfections with LPDV and parasites in turkeys but suggest that parasite infections are independent of LPDV infections. Ongoing work is currently investigating the sublethal effects of these coinfections on wild turkey populations.

Formalin, ethanol, and RNAlater are the most commonly used fixatives for morphological and molecular studies. Formalin is preferred for preserving tissue morphology, whereas ethanol and RNAlater are used to obtain high-quality nucleic acids for molecular analyses, including emerging -omics techniques. Over the past few years, the study of non-model organisms has gained attention, but the lack of laboratory cultures for many species requires collecting and fixing the animals directly in the field. Very often, just a few specimens are secured, limiting the possibility of using multiple fixatives for parallel analyses. A single fixative that preserves both morphology and molecules while being easy to handle in the field would therefore be highly valuable. KINFix, a non-toxic alcohol-based fixative, was developed to preserve histology, proteins, and nucleic acids simultaneously, enabling both morphological and molecular analyses with the same sample. Here, we evaluate the suitability of KINFix for electron microscopy, RNA preservation, and cell dissociation for single-cell RNA sequencing (scRNA-seq) experiments, using four invertebrate species from different spiralian phyla. Our results demonstrate that KINFix maintains RNA integrity for over 3 months, similarly to other standard fixatives, but also preserves morphology and cellular integrity even after cell dissociation, suggesting its suitability for scRNA-seq applications. While fixation conditions may require optimization for different species and tissues, our findings highlight KINFix as a cost-effective, versatile, and valuable fixative that enables a wide range of morphological and molecular studies in non-model invertebrates. KINFix is particularly useful for field-based research where sample availability and preservation logistics are especially challenging.

The mirid bug Apolygus lucorum (Meyer-Dür), a major pest affecting tea, also poses significant threats to a wide range of other crops across China. Identifying the dominant predatory spiders of the mirid bug and their pest control functions can provide a scientific basis for developing biological control technologies for this pest in tea plantations. In this study, we calculated the dominant presence of these spider species and evaluated the phenological overlap with the population of A. lucorum. Additionally, DNA from field-collected specimens of spider species was analyzed by A. lucorum-specific primers to detect the presence of residual DNA from the mirid bug. Using the predator–prey functional response model, the predation efficiency of various adult spider species on A. lucorum was assessed in laboratory conditions by testing different prey densities. The results showed that the greatest temporal niche overlap was observed between Xysticus ephippiatus and A. lucorum. Molecular detection results showed that X. ephippiatus and Misumenops tricuspidatus had significantly higher detection rates of the mirid bug than other spiders. The functional response of lab predation indicates that the predation ability of different spider species on A. lucorum increases with the density of prey. The predation functions of both adult X. ephippiatus and M. tricuspidatus conform to the Holling-II model. At a high prey density, the predation quantity of adult X. ephippiatus is significantly higher than that of adult M. tricuspidatus. In conclusion, the spider X. ephippiatus demonstrates the greatest potential as a biological control agent against A. lucorum within an integrated pest management framework. This research offers valuable scientific insights for leveraging predator species to effectively manage A. lucorum populations in tea plantations.