Ecology and Evolution最新文献

The study examines alloparental care and adoption in the Sri Lankan leopard population at Yala National Park, Sri Lanka. Using the multi-point leopard identification method, it documents a remarkable instance: a leopard cub initially adopted by its maternal aunt and later by an unrelated female with no prior connection to the cub. The cub had a sibling litter mate, who was not seen in the park after the initial adoption ended by the maternal aunt. We consider this behavior noteworthy in especially solitary animal species such as leopards. Our study was conducted for a period of 2 years and 5 months (from February 2021 to July 2023). Our observations highlight the dynamics of these adoptions and the behaviors exhibited. Altruistic acts, such as feeding, brushing, and shielding the cubs, were observed. These inspections challenge the conventional knowledge regarding leopard behaviors. Notably, the adoption of the cub by unrelated females, despite the absence of genetic ties, exemplifies a form of mutually beneficial reciprocal altruism, offering advantages to both parties. The following study explains leopard adoptions using evolutionary theories like kin altruism and reciprocal altruism. It suggests factors such as genetic relatedness, mutual dependency, and possible misidentification influenced the act of adoption. These rare altruistic acts benefit the leopard population. Our study opposes traditional concepts of solitary Sri Lankan leopards. Altruistic behaviors, influenced by genetic relatedness and reciprocal benefits, emphasize social dynamics in predator populations. These findings enhance the understanding of evolutionary mechanisms and cooperative behaviors in maintaining population fitness in the Sri Lankan leopard population.

The Atlantic blue crab, Callinectes sapidus, has rapidly expanded its invasive range ubiquitously in the Mediterranean Sea, posing ecological threats to native ecosystems. In its native habitat, the crab plays a crucial role in the ecosystem, but in invaded areas, it lacks natural predators. This has led to rapid expansion, highlighting the need to monitor and understand biological interactions with the native community. This study reports, for the first time in the wild, the predation of the invasive blue crab by the common octopus, Octopus vulgaris, in the Mediterranean Sea. Three sequences (two videos and a photography series) recorded by two spearfisherman (observation 1 and 2) and a recreational SCUBA diver (observation 3) are described. This article highlights the importance of native predators in influencing the expansion or control of invasive species. Additionally, it showcases the capacity of a versatile predator (the octopus), to serve as an ally alongside the fishing strategy, suggesting a novel perspective for ecologically sustainable management, in a context of low native predators of the blue crab. The collaboration with citizen scientists proves crucial in expanding our understanding of predator–prey dynamics and ecological interactions, underlining the need for continued partnerships between researchers and society for effective invasive species management.

Rhododendron bailiense was identified as a new species in 2013, with approximately 150 individuals existing globally, found only in Dafang County and Panzhou City, Guizhou Province, China. Despite its discovery, the genetic diversity and population structure of this species remain poorly understood, hindering efforts to collect and conserve wild germplasm resources. In this study, double digest restriction-site associated DNA sequencing was conducted on 26 samples from two populations of R. bailiense to identify single nucleotide polymorphism (SNP) loci. Using these data, the research explores the genetic diversity and structure of R. bailiense populations and infers their population dynamics and evolutionary history. The results indicate that R. bailiense has a moderate level of genetic diversity (π = 0.2489, H_o = 0.2039, H_e = 0.2331). Genetic differentiation between populations is relatively high (55.94%), with a genetic differentiation coefficient (F_ST) of 0.1907. This suggests that R. bailiense historically might have been a large population, which, due to geological historical events, became fragmented into the two existing populations. The Panzhou population demonstrates a heterozygote selection advantage. Conversely, the Dafang population faces the risk of inbreeding depression, further exacerbated by its limited gene flow. Consequently, in situ conservation is recommended for the Panzhou population, while ex-situ conservation is suggested for the Dafang population. Additionally, research on breeding techniques is necessary to expand the population size while maintaining high genetic diversity.

Understanding biodiversity is essential for preserving the stability of river ecosystems. However, the impact of landscape configurations and seasonal variations on biodiversity within undammed river ecosystems remains unexplored. Therefore, we selected the Chishui River—a naturally flowing tributary of the upper Yangtze River—for a survey of periphytic algae. The present study focuses on the seasonal fluctuations in the β-diversity of periphytic algae within the Chishui River and its correlation with the surrounding landscape patterns. Our findings indicate that there is a substantial influence of seasonal variations on the community structure and β-diversity of these algae within the Chishui River ecosystem. Concurrently, we observed that the turnover component predominantly contributes to β-diversity. In light of these findings, we recommend that conservation measures be implemented across the entire Chishui River basin to safeguard the regional biodiversity. Redundancy analysis elucidated that water temperature, conductivity, and pH were the primary environmental drivers shaping the structure of periphytic algal communities. Furthermore, additional analyses using a random forest model indicated that landscape fragmentation and complexity were key determinants of β-diversity in algal communities. Notably, the number of landscape patches was strongly correlated with the β-diversity of periphytic algae. It is important to highlight that maintaining an optimal balance between the number of patches and their size is crucial for enhancing the ecosystem's capacity to preserve biodiversity. In summary, our findings provide insights into the interplay between biodiversity and land-use practices within complex riverine environments, thereby offering a scientific foundation for the conservation and management of these ecosystems.

Rotational shifting cultivation (RSC) is a traditional agricultural practice in mountainous areas that uses fire to clear land after cutting vegetation for cultivation. However, few studies have assessed the effect of fire-deposited charcoal on the diversity and composition of soil microbial communities, and none have been conducted in Thailand. Therefore, this study was conducted 1 year after a fire in an abandoned 12-year RSC in Chiang Mai Province, northern Thailand. Charcoal samples were collected from the surface litter layer, while charcoal-soil mixtures were taken from the surface soil (0–2 cm). Soil samples from 2 to 7 cm captured the charcoal-soluble layer, and samples from 7 to 15 cm represented soil without charcoal incorporation. The results revealed that charcoal led to higher pH and electrical conductivity in the charcoal layer, with notable differences in soil texture across layers, including the highest sand and silt content in the charcoal-mixed soil layer (0–2 cm). Soil organic matter and total nitrogen were significantly higher in the charcoal-mixed layer compared to deeper layers, indicating improved nutrient retention due to charcoal presence. Enhanced microbial diversity was observed in the charcoal and charcoal-mixed soil layers, with Proteobacteria, Chloroflexi, and Planctomycetota dominating across all soil samples. The bacterial genus Ilumatobacter exhibited significant changes in abundance in the charcoal layer. Additionally, Pseudolabrys was more abundant in charcoal-leached soil, while JG30a-KF-32 showed greater abundance in soil without charcoal. Shifts in Proteobacteria and Planctomycetota abundance were evident in the charcoal leaching and non-charcoal layers. Network analysis indicated more complex bacterial interactions in the charcoal-mixed soil layer, with reduced network complexity observed in the charcoal leaching layer and the layer without charcoal. These findings imply that charcoal provides a favorable environment for diverse and interactive bacterial communities, potentially benefiting soil health and fertility recovery in RSC fields.

Cleaning interactions between mammals and birds have been widely observed worldwide. Here, we report cleaning interactions between sika deer and crows in Japan, based on a field observations using camera traps and online research. Online research was performed on social media platforms such as X (formerly Twitter), YouTube, and personal blogs. We finally collected 27 cases of cleaning associations between sika deer and crows. Crows associated with male more than female deer and mainly pecked their heads or necks, suggesting that crows remove Ixodid ticks from the deer's surface. Given that ticks on sika deer are vectors of several zoonotic pathogens such as Rickettsia and Borrelia spp., further studies should be conducted to examine the roles of crows as biocontrol agents of ticks and tick-borne diseases.

To effectively protect wild bee pollinators and the services they provide, it is critical to gather data on their distributions, life histories, and interactions with plants among a diversity of habitat types. Wetlands are underrepresented in bee surveys, despite having a great diversity of flowering plants and known importance to hundreds of species of wildlife. In this 2-year survey of a restored wetland complex in Central New York, over 9000 bees were collected, representing ≥ 109 species in 25 genera. We recorded 337 unique plant–pollinator associations, including those previously undocumented for the wetland obligate masked bee, Hylaeus nelumbonis (Robertson). Floral resources and bee genera were most diverse in August, and network analyses indicated September networks were the most connected, nested, and least modular. Floral resources also shifted towards being more native over the course of the season. Results show that emergent wetlands support diverse guilds of pollinators in the latter half of the growing season, and that wetland management can produce diverse conditions conducive to wild bee habitat.

The mechanism of community stability is a hot topic in the field of ecology. Research on the stability of the grassland community has gradually increased, and the reseeding of native species is one of the main measures to restore the degraded desert steppe in northwest China. However, little is known about the changes in the stability of the plant community in the desert steppe after reseeding native species. This study established a long-term observation site for native species reseeding in the desert steppe. We established reseeding and grazing exclusion plots in May 2017 and conducted surveys on degraded grasslands (0YEX(RS)) before setting up reseeding and grazing exclusion treatment experimental plots. After 3 and 6 years of setting up the test, the vegetation restoration status of the plot was investigated, respectively. The results showed that reseeding native species increased the Shannon-Wiener index and Margalef index of the community. At the same time, the importance value and the breadth of the niche of gramineous plants improved, while the proportion of pairs of high niche overlaps and the logarithm of significant association decreased. The general association of reseeding of the desert steppe was positively correlated, and the stability of the community gradually increased. The results of partial least squares path modelling show that reseeding has a highly significant positive effect on community stability. Both the EX (grazing exclusion grassland) and RS (reseeded grassland) models indicate that niche and diversity indices influence community stability to varying degrees, while interspecific linkage coefficients affect mainly niche overlap. Our research has shown that reseeding native species can improve the intensity of competition between species for resources, leading to a more stable community and ultimately increasing species diversity and community stability. These findings provide valuable theoretical support for vegetation restoration and sustainable management in the desert steppe.

Birds can cause significant damage to agricultural fields, notably in Europe, where corvid species like carrion crows (Corvus corone) and rooks (Corvus frugilegus) target spring crops, posing challenges for conservation and wildlife management. Among targeted crops, sunflower and maize suffer the highest levels of damage from corvids' foraging. While both lethal and non-lethal strategies are employed to mitigate bird damage, their effectiveness is limited and context-dependent. Consequently, there is growing interest in identifying natural bird repellents. To improve our understanding of corvid food selection and explore potential non-lethal management strategies, we conducted (1) cafeteria trials with five common seed types (maize, sunflower, soy, pea, and wheat) and (2) two-choice color tests with maize seeds in four colors (blue, green, orange, and red) on an urban population of carrion crows accustomed to human presence. Results indicated a marked preference for sunflower and wheat, while soy and pea were largely avoided, and maize was moderately consumed. The crows also demonstrated a preference for green-colored maize over blue, orange, red, and natural maize seeds. These findings suggest that strategic planting of preferred crops like wheat alongside sunflower or maize may help mitigate damage. Further, incorporating colors into repellent seed coatings could reinforce the aversive learning process in birds, although color may play a less significant role in food selection when seeds are sown.

Specimens stored within museum collections are increasingly leveraged to reconstruct historical baselines to both decipher the legacies of past anthropogenic impacts and anticipate the consequences of future climate change on species distributions. However, the research significance of such collections can be severely constrained based on their curation histories, resulting in data being forgotten, if not lost entirely. In this Nature Note, we report the unexpected presence of a mislabeled Black-capped Petrel (Pterodroma hasitata) specimen in the historical Middlebury College Vertebrate Natural History collection, potentially representing the rediscovery of a lost specimen reported from Vermont following the 1893 New York City Hurricane. We conducted archival research at multiple institutions to substantiate the reporting of a Black-capped Petrel specimen that was “missing” from Vermont in 1893, as noted in the Vermont Breeding Bird Atlas. We further substantiated the 19th-century age of this specimen through X-ray fluorescence analysis of mercury and arsenic of more than 200 whole bird bodies and feathers across the majority of the Middlebury College collection as part of an environmental health and safety assessment. This record expands the known vagrant range of the Black-capped Petrel. This research likewise highlights the critical role of small museum collections play in piecing together historical datasets and informing modern conservation, emphasizing the importance of their preservation and digitization.