Integrative zoology最新文献

Biodiversity monitoring is a crucial component of conservation, providing essential information on species occurrence, population dynamics, community composition, and ecosystem structure. Recently, to enhance wildlife protection, passive acoustic monitoring (PAM) technology has been developed based on animal sound characteristics and has become an important tool for wildlife monitoring. The vast amount of data generated by PAM has been transformed by the "big data" revolution, and research methods that integrate artificial intelligence (AI) with efficient and powerful machine learning models are rapidly advancing. The primary challenge is to isolate the vocalization data of target species from this massive dataset and to determine whether the developed methods can be applied to other species. In this study, we focused on the acoustic signals of a critically endangered white-headed langur, a primate species endemic to China. Unlike traditional methods that transform sound frequencies into spectrogram images, our approach uses a Deep Audio Detection Network (DeepADN) that directly converts audio into acoustic features, which are then fed into a convolutional neural network for accurate detection of white-headed langur calls, even in noisy environments. Our method optimized detection performance, achieving a recall rate of 98.22% and reducing manual review workload by 87.07%. Furthermore, DeepADN demonstrated cross-species applicability by successfully detecting François' langur calls, highlighting its potential for broader conservation monitoring efforts.

Predator cues have profound impacts on the behavior and physiology of prey animals. However, the mechanisms underlying stress responses induced by chronic exposure to predator cues in mammals, particularly the role of the gut microbiota, remain insufficiently understood. This study investigated how gut microbiota contributes to behavioral and physiological responses in Brandt's voles (Lasiopodomys brandtii) under chronic predator odor exposure. Adult voles were repeatedly exposed to cat feces odor (CO) for 18 days (1 h/day), followed by behavioral tests to assess anti-predator and anxiety-like behaviors, hormonal measurements to evaluate basal hypothalamic-pituitary-adrenal (HPA) axis activity, and 16S rRNA sequencing to analyze gut microbiota composition. The results showed that repeated CO exposure increased anxiety-like behaviors and basal HPA axis activity in both sexes. However, anti-predator behaviors exhibited sex-specific responses: Males were habituated to repeated CO exposure by reducing freezing and alerting behaviors, whereas females consistently displayed concealing strategies, reflecting different adaptive strategies to prolonged predator threats. While CO exposure did not alter the α-diversity of gut microbiota, it significantly affected the β-diversity in females, including a reduction in the relative abundance of Treponema and Quinella. Cecal microbiota transplantation from female CO-exposed voles to naive recipients increased anxiety-like behaviors and basal HPA levels but did not alter anti-predator behaviors in the recipients. In contrast, male recipients showed no significant behavioral or physiological changes. These findings suggest that gut microbiota is involved in regulating anxiety-like behavior and HPA axis activity in female voles but has a limited regulating role in male voles.

Rodents are significant agricultural and public health pests in rural village settings. Traditional rodent control methods, such as poison baiting and locally made traps, are usually implemented by individual households when rodent abundance is high and often provide only short-term relief. Moreover, impacts on different pest species may vary, and changes to inter-specific interactions may have potential ecological consequences. This study examines the impact of community-wide daily trapping inside houses on the abundance and distribution of Rattus rattus and Mastomys natalensis in Kilombero District, Tanzania. In this area, R. rattus are typically found inside houses, while M. natalensis are found outside. Snap traps were deployed daily inside all houses in treatment villages, while control villages received no intervention. Rhodamine B (RhB) baits in exterior areas monitored the movements of rodents from these areas to houses. Intensive in-house trapping successfully reduced the abundance of R. rattus but not M. natalensis. M. natalensis increased its use of houses in treatment villages, with a significant rise in the proportion of individuals captured indoors and a significant increase in the proportion of these individuals that had consumed RhB compared to non-treatment villages. Our results suggest that M. natalensis benefits from the reduced presence of R. rattus by expanding its habitat use to include houses. These findings underscore the effectiveness of intensive trapping in controlling R. rattus but reveal potential ecological readjustments following community ecology principles, with habitat shifts by M. natalensis. This highlights the need for integrated, multi-species management approaches for sustainable rodent pest control.

The visual systems of subterranean mammals often exhibit significant physiological and structural modifications due to light-restricted habitats, as widely reported. However, as subterranean species with a relatively short divergence time from their above-ground relatives, Mandarin voles (Lasiopodomys mandarinus) have been the subject of limited research regarding their visual characteristics, and potential parallels in their visual system's environment-induced changes remain unclear. We systematically analyzed the visual system of Mandarin voles, using their above-ground sister species Brandt's voles (Lasiopodomys brandtii) and standard laboratory mice (C57BL/6J, Mus musculus) as reference controls. Behavioral results showed that Mandarin voles exhibit reduced visual function, including visual acuity (<0.02 cycles/degree) and depth perception. Anatomical examinations revealed structural remodeling in the retina and dorsal lateral geniculate nucleus (dLGN), characterized by a relative decrease in rods and an increase in cones within the retina compared to C57BL/6J mice, along with dLGN showing reduced volume but increased mature neuron density and connectivity compared to Brandt's voles and C57BL/6J mice. Notably, the primary visual cortex (V1) retained a conserved structure. An evolutionary dynamic analysis of vision-related genes identified pseudogenization of genes and contraction of gene families associated with retinol metabolism, crystallin proteins, signal transduction, and retinal structure. These findings suggest that Mandarin voles exhibited visual functional degeneration, structural remodeling of visual pathways, and pseudogenization of vision-related genes compared to surface-dwelling species. This study systematically characterized the visual features of Mandarin voles, providing novel experimental evidence for understanding environmental adaptation in mammalian visual systems.

Anthropogenic habitat fragmentation and climate change have significantly reduced the genetic diversity and adaptive potential of local populations in numerous species. However, the lack of comprehensive genomic data from local populations has hindered the accurate assessment of their threatened status, hindering the designation of effective conservation units. Museum specimens offer a valuable source of historical DNA, enabling insights into population structure and uncovering hidden genetic diversity. The Koklass Pheasant, a montane species distributed across Central and Southwestern China, is increasingly threatened by habitat loss and climate change. Here, we utilized whole-genome sequencing data of museum samples to decipher the population structure and assess genetic diversity of this species. We identified six distinct populations, five of which corresponded to known subspecies in China, while a newly discovered Sichuan population exhibited clear genetic differentiation. Historical demographic analyses revealed a shared historical trajectory, characterized by expansion following the Last Glacial Maximum and a decline starting around 10 Kya. Genetic diversity and mutational load were unevenly distributed across populations. Notably, the Anhui population, which inhabits a restricted and isolated range, exhibited the lowest genetic diversity and highest mutational load, rendering it particularly vulnerable. Furthermore, ecological niche modeling predicted that climate change will lead to the near-complete loss of suitable habitat for populations in Anhui and Southern China. These findings underscore the importance of incorporating genomic data from museum samples into conservation strategies and highlight the necessity of establishing conservation units based on genetic diversity and evolutionary significance to safeguard the future of threatened species.

Rodents are important reservoirs of zoonotic pathogens, and the Capillaria hepatica they carry pose a potential threat to public health in grassland ecosystems. Climate-driven changes in precipitation show complex effects on disease ecology, particularly in steppe grasslands where extreme weather events are becoming increasingly frequent. Here, to investigate the effects of precipitation patterns on the epidemic dynamics of C. hepatica in host populations, we conducted a 7-year manipulation experiment in twelve 0.48-ha field enclosures in semiarid steppe grassland. We found that rainfall increases in the early growing season intensified the infection rate and infection intensity of the parasite. Structural equation model demonstrated that additional precipitation indirectly affected epidemic dynamics by changing population parameters including body weight and population size. On the other hand, C. hepatica in the enclosure also exhibited obvious male-biased parasitic characteristics, which were not observed in the wild population. In brief, our results provide experimental evidence for the impacts of rainfall patterns on parasite epidemiological dynamics at population level and highlight the importance of early rainfall increase on the parasite transmission in the semiarid grassland.

Understanding the synergistic mechanisms through which climate change and anthropogenic activities affect landscape connectivity is crucial for species persistence. While extensive research has documented their effects on habitat loss and fragmentation, how they drive spatio-temporal connectivity dynamics remains poorly understood. This study integrated field surveys and the meta-analytical data to model habitat suitability and quantify spatio-temporal connectivity of minimum area requirement (MAR) habitats for the karst-endemic primate François' langur (Trachypithecus francoisi) from 1987 to 2024. It concurrently evaluated the effectiveness of existing protected areas (PAs) in maintaining connectivity. Results revealed a 48.8% reduction in suitable habitat area, with the distribution pattern shifting from continuous to north-south isolation. Habitat centroids migrated northeastward at 1.2 km/year, exceeding the species' dispersal capacity. The MAR habitats threshold increased from 10.59 to 22.56 km², indicating intensifying ecological pressures. Average connectivity probability (PCst) decreased by 18.32%, and equivalent connected area (ECAst) declined by 38,130 km². Crucially, connectivity mechanisms shifted from within-patch persistence toward greater reliance on direct dispersal and stepping-stone pathways. Climate change and anthropogenic activities exhibited significant antagonistic effects on connectivity degradation, independent of species-specific MAR. Existing PAs significantly sustained connectivity, yet static management inadequately protected dynamic priority habitats and dispersal corridors. Through spatially explicit scenario modeling, this study deciphers species connectivity decline mechanisms under multiple stressors. We emphasize optimizing PA networks by reinforcing MAR core patches as ecological stepping stones and constructing climate-adaptive corridors to enhance functional connectivity, thereby improving conservation resilience for endangered karst-endemic species.

The Oligocene is a key period in South American mammalian evolution with diversification in groups such as notoungulates, sloths, and primates. While isotopic studies are abundant for the Neogene-Quaternary, Oligocene faunas remain understudied, with previous studies on Salla (Bolivia) and Gran Barranca (Argentina). This work presents δ¹³C and δ¹⁸O_CO3 isotope values from tooth enamel of several mammals (notoungulates, pyrotheres, and marsupials) from Quebrada Fiera (Mendoza, Argentina) to infer diets and to reconstruct the paleoenvironmental and paleoclimatic conditions; hypsodonty and body mass estimates are used for contrasting paleoecological inferences. Herbivores δ¹³C values (from -10.5‰ to -6.2‰) indicate a mosaic landscape including woodland-mesic C₃ grasslands and open woodland-arid C₃ grasslands. Nevertheless, annual precipitation estimates (∼203 mm/year) suggest a crucial role for (semi)permanent bodies of water to sustain such a patchy environment and a rich community of herbivores. The mean δ¹⁸O_CO3 value (25.5‰ ± 1.6‰) is intermediate between the values from Bolivia and Patagonia for the same period, suggesting the existence of a latitudinal gradient with more open and drier environments in lower latitudes. This would be associated with a stronger incidence of the rain shadow effect in the Central than the Southern Andes, likely reflecting regional differences in moisture sources. Importantly, this study reveals an overlap asymmetry in the isotopic niche associated with body size: smaller species exhibit significantly greater isotopic niche overlap, while larger species occupy more distinct isotopic spaces. These findings highlight the role of size-related ecological strategies in shaping community organization in the subtropical Andes rain shadow.

Morphological traits are central to traditional taxonomy, yet convergent and divergent evolution can lead to inconsistencies between morphological classification and molecular phylogenetics. The distinctive "sunken head and humpback" morphology of Cromileptes altivelis and its close phylogenetic relationship with Epinephelus make it an ideal model for evaluating the weighting of morphological traits in taxonomic classification and refining the classification system. We measured and analyzed the morphological specialization process of C. altivelis, identifying key developmental stages leading to its humpback phenotype. This trait develops through cranial remodeling, involving changes in the supraoccipital, frontal, and lateral occipital bones, with structural support from predorsal bones and the first neural arch and spine. Examining the Hox gene family, we found that C. altivelis possesses 49 highly conserved Hox genes, with no significant differences in gene copy number, arrangement, or exon count among groupers. However, unique amino acid variations were identified in the Hoxa7a, Hoxa10b, and Hoxc1a proteins of C. altivelis, which are otherwise highly conserved among other teleost fishes. Functional assays confirmed that mutations in these genes enhance gene transcription activity, promoting osteoblast proliferation and differentiation. qPCR analysis showed that the expression of hoxa7a and hoxa10b was significantly upregulated during the humpback stage, implicating their contribution to the morphological specialization of C. altivelis. hoxa10b remained elevated post-humpback, suggesting a role in bone strength and homeostasis, whereas hoxc1a exhibited consistently low expression, indicating limited involvement. Our findings provide insights into resolving taxonomic discrepancies in C. altivelis and offer a framework for understanding its adaptive evolution and speciation.