Explore the vast range of titles available.

Daily rhythms are found in almost all organisms, and they comprise one of the most basic characteristics of living things. Daily rhythms are generated and mainly regulated by circadian clock. Bats have attracted interest from researchers because of their unique biological characteristics. However, little is known about the molecular underpinnings of daily rhythms in bats. In this study, we used RNA-Seq to uncover the daily rhythms of gene expression in the brains of Asian particolored bats over the 24-h day. Accordingly, four collected time points corresponding to four biological states, rest, sleep, wakefulness, and active, were selected. Several groups of genes with different expression levels in these four states were obtained suggested that different physiological processes were active at various biological states, including drug metabolism, signaling pathways, and the circadian rhythm. Furthermore, downstream analysis of all differentially expressed genes in these four states suggested that groups of genes showed daily rhythms in the bat brain. Especially for  Per1 , an important circadian clock gene was identified with rhythmic expression in the brain of Asian particolored bat. In summary, our study provides an overview of the brain transcriptomic differences in different physiological states over a 24-h cycle.

The coevolution between the host and its gut microbes can promote an animal’s adaptation to its specific ecological niche and changes in energy and nutritional requirements. This study focused on an avivorous bat, the great evening bat ( Ia io ), to investigate how seasonal dietary shifts affect the gut microbial composition and function, thereby facilitating adaptation to an avian diet. Plasticity in the microbial community composition and function can permit the host to adapt to ecological, environmental, and physiological changes. Much of the information on the gut microbiota-host relationship to date derives from studies of laboratory model organisms, while little is known concerning wild animals and their ecological relevance to gut microbes. It is also unclear how microbial community composition and activity adapt to changes in diet and energy, nutritional requirements, and utilization induced by dietary expansion from invertebrates to vertebrates. The great evening bat ( Ia io ) is both an insectivore and an avivore (that is, a bird-eater), and thus provides an opportunity to investigate the diet-host-microbiota-physiology relationship. Here, we investigated this relationship by using 16S rRNA amplicon sequencing and functional prediction in adult males of I. io . We found that gut microbial diversity was similar, while microbial community structures were significantly different between insectivorous and avivorous diets. Moreover, increases in the relative abundance of Firmicutes and the Firmicutes -to- Bacteroidetes ratio, changes in carbohydrate and nucleotide metabolism, and a decrease in Pseudomonas were associated with higher energy demands for hunting birds and with fat storage for entering hibernation and migration. These findings demonstrated that seasonal dietary shifts drive a significant change in the composition and function of gut microbiomes, thereby facilitating adaptation to the challenging avian dietary niche in bats. These results suggest that the gut microbial communities can constantly respond to alterations in diets, potentially facilitating the diversity of wild animal dietary niches, and enhance our understanding of the diet-host-microbiota-physiology relationship. IMPORTANCE The coevolution between the host and its gut microbes can promote an animal’s adaptation to its specific ecological niche and changes in energy and nutritional requirements. This study focused on an avivorous bat, the great evening bat ( Ia io ), to investigate how seasonal dietary shifts affect the gut microbial composition and function, thereby facilitating adaptation to an avian diet. We found that seasonal dietary shifts driving a significant change in the composition and function of gut microbiomes in I. io were associated with higher energy demands for hunting birds and fat storage for entering hibernation and migration. Our study provides novel insight into the role of gut bacteria in generating ecological diversity and flexibility in wild mammals. The results are valuable for clarifying the complicated host-microbiota-physiology relationship in a dietary niche expansion context.

Understanding how climate change may reshape species distributions and affect the associated ecosystem services is critical for sustainable agricultural planning. In this study, we integrated dietary DNA metabarcoding with ensemble species distribution modeling to assess the current and future ecological roles of Miniopterus fuliginosus, a widespread insectivorous bat species in East Asia known for preying on nocturnal agricultural pests. Fecal samples were collected in 2023 from three biogeographically distinct regions of China—Central China (Henan Province) and Southwest China (Guizhou and Yunnan provinces). DNA metabarcoding based on COI gene amplification and Illumina sequencing revealed a consistent dietary dominance of Lepidoptera, particularly families comprising major agricultural pest species such as Noctuidae, Crambidae, and Geometridae. This trophic consistency suggests that M. fuliginosus functions as a moth-specialized generalist predator. Species distribution models were constructed using occurrence records from field surveys, the literature, and the GBIF database, integrating multiple algorithms (GLM, GBM, MaxEnt, RF, and FDA) within an ensemble modeling framework. Habitat suitability was then estimated under current climatic conditions and projected for future distributions under two contrasting climate scenarios (SSP1–2.6 and SSP5–8.5) for the 2050s and 2070s. While the total suitable area may remain stable or even expand, future projections indicate a progressive poleward shift in range centroids and a divergence in habitat structure. Specifically, SSP1–2.6 is associated with greater spatial cohesion (25.34–31.11%), whereas SSP5–8.5 leads to increased habitat fragmentation and isolation of suitable patches (27.12–33.28%). Overlaying the potential for pest control with habitat projections highlights emerging spatial mismatches between ecological function and climatic suitability, particularly under high-emission trajectories. Our findings underscore the importance of identifying ecological refugia and maintaining landscape connectivity to sustain bat-mediated pest control. This spatially explicit framework offers new insights for integrating biodiversity-based pest management into climate-resilient agricultural strategies.

The evolutionary divergence of animal vocalizations is a complex process shaped by various factors, including morphology, ecology, social pressure, and phylogenetic relationships. This applies even to distress calls, which may appear to be simple expressions of emotion. However, the relative importance of these factors in shaping interspecific divergence of distress call structure remains largely unexplored. In addition, previous studies concerning the factors driving distress call divergence have been mainly conducted in birds, anurans, and lizards, whereas less is known for mammals. Here, we recorded distress calls across 32 bat species belonging to 7 families, and compiled data on body size, foraging habitat types, climatic variables, colony size, and phylogenetic components, aiming to identify the key determinants predicting the cross-species divergence in the incidence and acoustic parameter of distress calls within a comparative framework. Our results supported that bats divergence in distress vocalizations is not an adaptive evolution in response to ecological and social pressure, but constrained by phylogenetic relationship and body size. Phylogenetic components explained the most interspecific variation in the incidence and temporal parameters of distress calls, whereas body size accounts for spectral parameters. This study has revealed that distress vocalizations not only convey the caller’s emotional state, but also suffer severe phylogenetic and morphological constraint.

Background Predator‒prey interactions and their dynamic changes provide frequent opportunities for viruses to spread among organisms and thus affect their virus diversity. However, the connections between dietary diversity and virus diversity in predators have seldom been studied. The avivorous bats, Ia io , show a seasonal pattern of dietary diversity. Although most of them primarily prey on insects in summer, they mainly prey on nocturnally migrating birds in spring and autumn. Results In this study, we characterized the RNA virome of three populations of I. io in Southwest China during summer and autumn using viral metatranscriptomic sequencing. We also investigated the relationships between dietary diversity and RNA virus diversity by integrating DNA metabarcoding and viral metatranscriptomic sequencing techniques at the population level of I. io . We found 55 known genera belonging to 35 known families of RNA viruses. Besides detecting mammal-related viruses, which are the usual concern, we also found a high abundance of insect-related viruses and some bird-related viruses. We found that insect-related viruses were more abundant in summer, while the bird-related viruses were predominantly detected in autumn, which might be caused by the seasonal differences in prey selection by I. io . Additionally, a significant positive correlation was identified between prey diversity and total virus diversity. The more similar the prey composition, the more similar the total virus composition and the higher the count of potential new viruses. We also found that the relative abundance of Picornaviridae increased with increasing prey diversity and body mass. Conclusions In this study, significant links were found between RNA virus diversity and dietary diversity of I. io . The results implied that dynamic changes in predator–prey interactions may facilitate frequent opportunities for viruses to spread among organisms. -pQNSPFCJqqnkMh129yG7y Video Abstract

The mysterious predator–prey interaction between bats and nocturnally migrating birds is a very rare and incredible process in natural ecosystems. So far only three avivorous bat species, including two noctule bats (Nyctalus lasiopterus and Nyctalus aviator) and the great evening bat (Ia io), are known to regularly prey on songbirds during nocturnal avian migration. The information related to the diversity and the characteristics of the birds as prey and the hunting strategy in both species of noctule bats are already clear. However, the diversity of bird prey in the diet of I. io as confirmed by molecular identification remains unknown. Moreover, like hunting insects, it remains unclear whether the avivorous bats opportunistically prey on birds. Here, we used DNA metabarcoding to investigate the bird prey composition, diversity, and choice in diets of I. io. We found I. io consumed 22 species of seven families from Passeriformes with a body mass of 6–19 g, and preferentially selected small‐sized passerine birds for optimizing the benefit/risk trade‐off. Moreover, most of the species preyed upon were migratory birds, while four species were local resident birds, indicating that I. io may adopt both aerial‐hawking and gleaning strategies on songbirds as do the other two noctules. Further, I. io body mass did not influence in prey choice and predation richness on birds, suggesting I. io is an opportunistic avivorous predator. This study provides novel insights into the avian dietary ecology of I. io and completes the analysis of predator/prey interaction between three avivorous bats and nocturnally migrating birds. Our results also indicate bat predation on birds which occurs as an act of ecological opportunity may subject bats to intense natural selection pressure, causing them access to the new diet‐defined adaptive zones. We used DNA metabarcoding to investigate the bird prey composition, diversity, and choice in diets of the avivorous bat, Ia io. We found I. io consumed 22 species of seven families from Passeriformes. Moreover, I. io may adopt both aerial‐hawking and gleaning strategies on songbirds as do the other two noctules. Ia io body mass did not influence in prey choice and predation richness on birds, suggesting I. io is an opportunistic avivorous predator. Our work provides novel insights into the avian dietary ecology of I. io and completes the analysis of predator/prey interaction between three avivorous bats and nocturnally migrating birds.

Background Mammals rely on the circadian clock network to regulate daily systemic metabolism and physiological activities. The liver is an important peripheral organ in mammals, and it has a unique circadian rhythm regulation process. As the only mammals that can fly, bats have attracted much research attention due to their nocturnal habits and life histories. However, few research reports exist concerning the circadian rhythms of bat liver gene expression and the relevant biological clock regulation mechanisms in the liver. Results In this study, the expression levels of liver genes of Asian particolored bats were comparatively analyzed using RNA-seq at four different time points across 24 h. A total of 996 genes were found to be rhythmic, accounting for 65% of the total number of expressed genes. The critical circadian rhythm genes Bmal1 , Rev-erbα , Cry, and Ror in the liver exhibited different expression patterns throughout the day, and participated in physiological processes with rhythmic changes, including Th17 cell differentiation (ko04659), antigen processing and presentation (ko04612), the estrogen signaling pathway (ko04915), and insulin resistance (ko04931). In addition, previous studies have found that the peroxisome proliferator-activated receptor (PPAR) metabolic signaling pathway (ko03320) may play a vital role in the rhythmic regulation of the metabolic network. Conclusions This study is the first to demonstrate diurnal changes in bat liver gene expression and related physiological processes. The results have thus further enriched our understanding of bats’ biological clocks.

On the basis of molecular and morphological studies of samples collected in China, a new Myotis species belonging to the siligorensis group is described, Myotis kalkoae Tiunov, Jiang, & Liu, sp. nov. The species rank of M. sowerbyi and M. alticraniatus was confirmed. All three taxa under consideration belong to different genetic lines and can be distinguished from each other and from other morphologically similar species based on the shape of their baculum and tragus. The difficulties of taxonomy within the M. siligorensis species group are discussed.

Predation risk has profound effects on prey from phenotype to gene expression. Prey may respond differently to predation risk on the basis of sex, especially those species with obvious sexual size dimorphism. However, whether such responses are sex‐specific still lacks systematic research. In this study, we continuously exposed a female‐larger species Asian corn borer (ACB, Ostrinia furnacalis) to bat foraging ultrasound from the larval stage through adulthood, monitoring phenotypic and gene expression changes in exposed males and females compared to normally reared adults. The results revealed that adults in the ultrasound‐stressed group exhibited significant changes in both phenotypic traits and gene expression profiles, with marked sex‐specific responses to auditory predation cues. Specifically, males demonstrated significant increases in body weight, body length, and ecdysteroid titer, whereas females displayed a marked reduction in fecundity (egg production). Female adults exhibited a predominance of downregulated differentially expressed genes (DEGs), with greater total DEG numbers compared to males. Male adults showed primarily upregulated DEG profiles. Females appear to utilize LOC114365575 and LOC114352210 as key regulators in modulating growth and juvenile hormone levels, whereas males may rely on LOC114349799 and LOC114351933 to regulate growth and electrophysiological response amplitude under predation risk. Our results suggest that sex‐specific responses may be an important component of inter‐individual differences in prey responses to risk and influence prey population growth and demography. Females downregulate more DEGs; males upregulate under predation risk. Males boost ecdysteroid; females reduce fecundity under bat ultrasound. Female O. furnacalis reacted more strongly to auditory cues of bats than males.

Mammals rely on an intricate network of circadian clocks to regulate daily metabolic and physiological processes throughout the body. The liver, as a key peripheral organ, plays a crucial role in coordinating circadian rhythms and metabolic regulation. Bats, the only mammals capable of true flight, present unique nocturnal behaviors, which have garnered significant research interest. However, the daily metabolic fluctuations in bat liver and the underlying mechanisms of circadian regulation remain largely unexplored. To elucidate the metabolic foundations and rhythmic patterns in bat liver, a comparative LC–MS analysis was conducted to characterize the type, composition, and abundance of metabolites in the liver of Asian particolored bats at four distinct time points throughout a single day. This analysis identified a total of 7211 metabolites, with approximately 2.0% exhibiting significant rhythmicity, though with varying rhythmic patterns. Integrating these findings with RNA‐Seq data revealed that differentially expressed genes and differentially accumulated metabolites were significantly enriched in two key pathways: the protein digestion and absorption pathway and the glutathione metabolism pathway. Notably, our results suggest that L‐glutamate and L‐tryptophan may play pivotal roles in the metabolic regulation of hepatic circadian rhythms, as indicated by metabolomics analysis. This study provides a systematic examination of the cyclic variations in metabolites within the bat liver, uncovering the physiological and biochemical processes involved and thereby enhancing our understanding of the molecular mechanisms governing circadian rhythms in bats. This study elucidated the composition of liver metabolites and clarified the rhythmic patterns of critical metabolites and associated physiological processes in the bat liver. The circadian‐regulated metabolic patterns in bats may have significant implications for their energy strategies and survival. Antioxidant‐related physiological processes are activated both before and after bats' energy‐intensive flight behavior, preparing and protecting the body from oxidative stress.