Ecology and Evolution最新文献

Across Europe, landscapes where large carnivores, large herbivores and human communities coexist are expanding, reflecting the widespread recovery of large mammal populations in recent decades. The influence of top-down effects of wolves on large herbivores has been extensively studied in areas with relatively little anthropogenic disturbance, but less is known about their effect in human-dominated landscapes. We systematically collected camera-trap data over five consecutive autumn hunting seasons in an area of the eastern Alps which is intensely frequented by tourists and trekkers, and partially open to ungulate hunting. We used a quasi-experimental design, with half of the sampling sites located within nonhunting areas and half outside. Applying generalised additive mixed models (GAMMs) with cyclic cubic splines we investigated the effect of wolf, as well as lethal (hunting) and nonlethal (recreational) human activities on red deer spatiotemporal activity pattern. Similarly, we analysed the effect of recreational activities and red deer site-use on the spatiotemporal activity pattern of wolves. Hunting was associated with overall lower red deer activity, as well as reduced dawn–dusk peaks and diurnality. Crucially, hunting interacted with outdoor recreation exacerbating its impact, with major changes to red deer activity curve. Wolf site-use did not have a significant effect on the shape of red deer temporal curve. Wolves were markedly more active in areas highly used by red deer, and remained strongly nocturnal even where human activity was scarce. Our results show that humans, through both lethal and nonlethal activities, elicit stronger responses in red deer than their natural predator. Behavioural constraints imposed by humans on red deer, coupled with the cursorial predatory strategy of wolves, likely limit the possibility of wolf avoidance by red deer. In human-dominated European landscapes, human disturbance can therefore override natural predator–prey dynamics, reshaping behavioural landscapes and potentially increasing predator and prey spatiotemporal co-occurrence.

Savannahs are among the most threatened ecosystems in the world due to the rapid change in their land use for forestry, soybean cultivation, and pasture. However, savannahs are less studied than tropical forest ecosystems despite this intense anthropogenic pressure. As such, here we investigate the gaps and trends in scientific research on terrestrial vertebrates in tropical savannahs, via a systematic search for scientific articles on the Web of Science platform. Subsequently, to identify the geographic distribution of the studies, we divided the total number of articles by the area of the Savannah biome (in km²) that occurs in each country. Our results show that Africa has a deficit in scientific research on terrestrial vertebrates compared to Oceania and South America, and that this global trend in the distribution of studies is closely related to the Human Development Index. We also identified land use change and fire dynamics as the most studied drivers of biodiversity loss, while invasive species and climate change were the least well studied. Finally, our research revealed that about 80% of the articles focused on mammals and birds, and that phylogenetic and functional diversity were the least studied dimensions of vertebrate biodiversity in tropical savannahs. These results are concerning for conservation efforts, as they reveal not only a substantial geographic gap but also a limited and biased understanding of savannah biodiversity.

Inland waters face escalating anthropogenic pressures, driving an unprecedented collapse in freshwater biodiversity. Enhanced knowledge of aquatic taxa is essential to reverse this decline. Chironomidae (non-biting midges), often the dominant zoobenthic group in freshwater ecosystems, remain poorly documented globally. Here, we provide the first integrative assessment of Chironomidae biodiversity in Hong Kong through a year-long survey of five streams. Integrative taxonomy expanded the known species in Hong Kong from 17 to 243, and yielded a reference library of 827 cytochrome c oxidase subunit I (COI) barcodes representing 225 species. Beta-diversity partitioning revealed that community dissimilarity was primarily driven by species turnover, which was strongly associated with environmental gradients but only weakly related to geographic distance. Variation partitioning revealed that environmental factors explained slightly more variation in community composition (9.0%) than spatial factors (6.7%). These patterns indicate that environmental filtering and mass effects play key roles in structuring Chironomidae metacommunities in Hong Kong, with dispersal limitation exerting little influence. Cross-database barcode matching analysis suggested that Hong Kong fauna is predominantly tropical-to-subtropical, with the strongest affinities to coastal East and Southeast Asia (e.g., eastern China, Thailand, Malaysia). Many species displayed wide geographic ranges, likely facilitated by high passive dispersal and broad ecological tolerances. This study delivers the first robust biodiversity baseline for Hong Kong Chironomidae and a well-curated DNA barcode library. These resources will benefit taxonomic refinement and eDNA-based biomonitoring, strengthening conservation of human-impacted freshwater ecosystems.

Sex in marine turtles is determined by incubation conditions, raising concerns of population feminization and loss of genetic diversity due to warming temperatures. Demographic data on breeding males are limited due to their relative inaccessibility. Hatchling sampling can inform multiple paternity (MP) and breeding sex ratios (BSR) but is logistically intensive, limiting the number of nests and populations analyzed. Here, we present a novel approach to characterize successfully breeding males by genotyping sperm trapped in the perivitelline membrane (PVM) surrounding the yolk of a single egg per clutch. We compared maternal genotypes via eggshells with PVM extract genotypes from 27 loggerhead turtle (Caretta caretta) eggs and 13 green turtle (Chelonia mydas) eggs from Melbourne Beach, Florida, USA, at 16 and 13 microsatellite loci, respectively. Sampled offspring genotypes (620 loggerhead and 1117 green turtle) provided ground-truthing of PVM sperm allele detections. Paternity analyses resolved 38 loggerhead and 29 green turtle sires, all but two of which were correctly inferred via PVM allele calls. All paternal alleles representing single paternity clutches and primary contributors of multiply sired clutches were detected in the PVM genotypes except in one case of maternal DNA swamping of the PVM. Seven of eight sires that contributed ≤ 11% of offspring were detected via PVM genotyping, comparable to inferences based on sampling 20 hatchlings per nest. PVM-inferred paternal genotypes from single-paternity clutches were > 99% concordant with reconstructed sire genotypes in both species. Although destructive to a single egg per clutch, this method is non-invasive to nesting females and hatchlings. Its scalability across space and time enables long-term monitoring of MP and BSR, key demographic metrics for assessing population viability under climate change. Male genotypes generated from the PVM in single paternity nests may also inform population assignment, assessments of genetic connectivity, and relatedness analyses.

Adaptive radiations of freshwater fishes are based on the partitioning of trophic resources as sympatric forms diverge and end up occupying unique and specialized trophic niches. It remained unknown how these specialists responded to recent human-induced ecosystem disturbances. Here, we tested how the species with various degrees of tropho-ecological specializations (generalists vs. specialists) of Lake Tana Labeobarbus spp. flock reacted to the ongoing detrimental human-induced ecosystem transformation and the resulting drastic population declines. In late 2022, we collected adults of the still remaining species to examine current niche partitioning within the assemblage based on the analyses of muscle stable isotope ratios and fatty acid compositions as time- and space-integrated tropho-ecological markers. The data revealed one niche for the generalized omnivorous labeobarb, four distinct niches for the nonpiscivorous, as well as three discernible niches for the piscivorous labeobarbs. Of the 11 species caught in the lake, only two pairs showed demonstrably large niche overlap. Of all the species in the Lake Tana species flock, the top (piscivorous) predators were the most strongly affected by the disturbance in ecological parameters, which resulted in altered and narrowed niches. This suggests that most of the endemic labeobarb species still retain their original, stable, and distinct diets and habitat preferences that appeared to have maintained the overall ecological relationships in Lake Tana. We also detected that some species apparently changed their diet, seemingly adapting to human-induced habitat disturbances and large population declines during the last decades.

Climate change is driving species to shift their distribution ranges, potentially altering the level of genomic structuring and connectivity between populations. Additionally, fishing practices might further reduce genomic diversity and limit the potential adaptability of species to environmental changes. We use whole-genome sequencing for the first time to explore current and historical patterns of genomic diversity in European hake (Merluccius merluccius) from the Northeast Atlantic, focusing on the recently expanded distribution range in the North Sea. Genomic data revealed a complex scenario in the North Sea and neighbouring regions, with three distinct populations: North Sea, Celtic Sea and Portugal. Individuals from the Kattegat, Skagerrak and west coast of Denmark were highly differentiated from those in the Celtic Sea and waters around Ireland. The Northern North Sea appears as a transition zone, with individuals from higher latitudes assigned to the Celtic Sea group and those from lower latitudes to the North Sea group. The more distant Portuguese individuals appeared as a third distinct population. Although the differentiation among these populations was shallow when the entire dataset was used, a subset of 99,364 outlier markers revealed a much deeper divergence. Demographic analyses indicated that these populations are relatively young and have large effective population sizes and thus without sufficient time to build a signature of differentiation by genetic drift. At the same time, selection for local adaptation is strong enough to overcome the effects of contemporary gene flow. Our findings have important implications for managing the European hake stocks in the Northeastern Atlantic, highlighting the need for management measures that address shifts in species and population distribution due to climate change, as well as needing to account for different populations contributing to fisheries within a single stock. Preserving the genomic diversity within and among fish stocks is crucial for maintaining the long-term resilience of marine ecosystems and the services they provide.

The family Chironomidae, particularly the subfamily Tanypodinae, represents a significant component of freshwater ecosystems. This investigation sought to clarify the evolutionary affinities within Tanypodinae by leveraging whole-mitochondrial genome data. We generated the inaugural full mitogenomic sequences for 22 Tanypodinae taxa, added the mitochondrial genome sequence of another individual of Thienemannimyia tripunctata, merged these novel records with previously released chironomid mitochondrial genomes, and performed an integrated comparative mitogenomic survey encompassing 55 Tanypodinae species together with nine outgroup representatives from allied genera. The mitogenomes were characterized through de novo assembly, annotation, and comparative analysis. Our results demonstrated that the mitogenomes of Tanypodinae species exhibit a conserved structural organization, with the majority of genes arranged in the typical insect gene order. Phylogenies were reconstructed via Bayesian Inference (BI) and Maximum Likelihood (ML) analyses of the amino-acid alignments of 13 protein-coding genes (PCGs), corroborating the monophyly of tribe Pentaneurini and the sister-group affinity between Procladiini and Tanypodini. These outcomes furnish novel insights into the evolutionary characteristics and phylogenetic framework of Tanypodinae while substantially expanding the mitogenomic archive for Chironomidae.

Ingestion is the process of consuming a resource and is a component of an organism's handling time, which can limit the acquisition of additional resources and decrease predation rate. If a predator spends more time handling prey, it will have less time to seek out additional prey. Variation in ingestion may therefore impact energy fluxes and ecosystem stability. Body size has been proposed to affect ingestion, with larger organisms predicted to have a reduced handling time, potentially scaling like metabolic rate. The goal of this study was to examine the allometric relationships of ingestion, a proxy for handling time, among praying mantis species with different camouflage strategies in a phylogenetic context. We measured the time it takes adult female mantises to ingest a standard prey using time-lapse photography in 1–8 individuals among 14 species of Mantodea 3–5 times, resulting in 324 trials from 66 individuals. We examined the scaling of ingestion in relation to mantis body size using both a phylogenetic general linear mixed model to account for within-species variation, as well as a phylogenetic generalized least-squares approach on species means. We also compared the scaling of our praying mantis ingestion allometry to other allometric relations of other organisms from a larger database (e.g., other insects, arachnids, and vertebrates). We found that the ingestion rate and time scale with a power-law function regardless of the camouflage strategy. We also found that mantis prey-mass-specific ingestion scaled more like arachnids than insects when compared to the larger database. Comparing our scaling of ingestion to published values of metabolic scaling, we found a higher slope for ingestion. Together, our results suggest that larger praying mantises can ingest more resources than may be needed based on their metabolic rate, which may influence their role in the ecosystem.

Topographically complex mountainous regions are widely recognized as important for biodiversity conservation due to their environmental heterogeneity, which can promote species turnover, niche differentiation, and the persistence of specialized taxa. Such landscapes are often associated with high biodiversity value and provide critical resources and connectivity for wildlife and human communities. In this study, we deployed 131 camera traps to assess the occupancy of 34 mammal species in relation to key topographic variables in a semi-arid mountain catchment in South Africa. Multispecies occupancy models were used to evaluate the probability of habitat use concerning topographic complexity, characterized by features such as catchment aspect, slope, ruggedness, solar gain and landscape units. The results identified floodplains, valleys, low slopes, and areas with low ruggedness as biodiversity hotspots, offering critical resources like water and forage and supporting high species richness. Conversely, steep slopes, rugged terrains, and high solar gain areas, while supporting fewer species, served as critical refuges for specialized taxa such as leopard, klipspringer, caracal, and grey rhebok. While topographic features like ruggedness may have a limited impact at the community level, their importance becomes more pronounced at the species level. This study underscores the value of incorporating detailed topographic metrics into ecological research, particularly in mountainous landscapes where these features govern species distribution. Conservation strategies should integrate both community-level and species-specific monitoring approaches to safeguard the unique biodiversity and ecological dynamics of topographically complex mountain landscapes.

Freshwater ecosystems are central but overlooked in frameworks addressing the biodiversity-climate-health nexus. Among their inhabitants, freshwater snails occupy a unique position at the intersection of ecology, evolution, and disease. They are both sentinels and mediators of environmental change—sensitive to climatic fluctuations, pollutants, and habitat degradation—while serving as intermediate hosts of major zoonotic parasites such as Fasciola and Schistosoma spp. Their amazing ecological plasticity, diverse reproductive systems, and capacity for rapid adaptation make them powerful yet under-used models to explore how multiple stressors shape biodiversity dynamics, host-parasite interactions, and disease risk. Here, I advocate for the recognition of freshwater snails as integrative model systems linking eco-evolutionary processes with epidemiological outcomes under global change. Their study can reveal general principles on adaptation to multi-stressor environments, community assembly, and vector competence evolution—core questions in both ecology and One Health. I propose a conceptual framework situating freshwater snails at the biodiversity-climate-health nexus to stimulate interdisciplinary research bridging evolutionary ecology, epidemiology, and freshwater conservation. Recognizing these neglected organisms as “nexus sentinels” can advance our understanding of how global change reshapes ecological and health outcomes across aquatic ecosystems.