摘要:

摘要: Sleeping site selection is essential for understanding primate behavioral ecology and survival. Identifying where species sleep helps determine priority areas and critical resources for targeted conservation efforts. However, observing sleeping sites at night is challenging, especially for species sensitive to human disturbance. Thermal infrared imaging (TIR) with drones is increasingly used for detecting and counting primates, yet it has not been utilized to investigate ecological strategies. This study investigates the sleeping site selection of the Critically Endangered black-shanked douc langur (Pygathrix nigripes) in Cat Tien National Park, Vietnam. Our aim is to assess the feasibility of using a TIR drone to test sleeping site selection strategies in non-nesting primates, specifically examining hypotheses related to predation avoidance and food proximity. Between January and April 2023, we conducted 120 drone flights along 22 transects (similar to 1-km long) and identified 114 sleeping sites via thermal imaging. We established 116 forest structure plots along 29 transects in non-selected sites and 65 plots within douc langur sleeping sites. Our observations reveal that douc langurs selected tall and large trees that may provide protection against predators. Additionally, they selected sleeping sites with increased access to food, such as Afzelia xylocarpa, which serves as a preferred food source during the dry season. These results highlight the effective use of TIR drones for studying douc langur sleeping site selection with minimal disturbance. Besides offering valuable insights into habitat selection and behavioral ecology for conservation, TIR drones hold great promise for the noninvasive and long-term monitoring of large-bodied arboreal species.

摘要: The family Erinaceidae encompasses 27 extant species in two subfamilies: Erinaceinae, which includes spiny hedgehogs, and Galericinae, which comprises silky-furred gymnures and moonrats. Although they are commonly recognized by the general public, their phylogenetic history remains incompletely understood, and several species have never been included in any molecular analyses. Additionally, previous research suggested that the species diversity of Erinaceidae might be underestimated. In this study, we sequenced the mitochondrial genomes of 29 individuals representing 18 erinaceid species using 18 freshly collected tissue and 11 historical museum specimens. We also integrated previously published data for a concatenated analysis. We aimed to elucidate the evolutionary relationships within Erinaceidae, estimate divergence times, and uncover potential underestimated species diversity. Our data finely resolved intergeneric and interspecific relationships and presented the first molecular evidence for the phylogenetic position of Mesechinus wangi, Paraechinus micropus, and P. nudiventris. Our results revealed a sister relationship between Neotetracus and Neohylomys gymnures, as well as a sister relationship between Hemiechinus and Mesechinus, supporting previous hypotheses. Additionally, our findings provided a novel phylogenetic position for Paraechinus aethiopicus, placing it in a basal position within the genus. Furthermore, our study uncovered cryptic species diversity within Hylomys suillus as well as in Neotetracus sinensis, Atelerix albiventris, P. aethiopicus, and Hemiechinus auratus, most of which have been previously overlooked. We estimated the evolutionary history covering the majority of the hedgehog and gymnure species in the family Erinaceidae worldwide using complete mitochondrial genomes. The result supported an underestimated species diversity in this overlooked group of mammals. image

摘要:

摘要:

摘要: Gut mycobiota are part of the gut microbiome, typically derived from the host diet and living environment. In this study, we examined the gut mycobiota of three snub-nosed monkeys: Rhinopithecus roxellana, R. bieti, and R. strykeri using next-generation amplicon sequencing targeting the fungal internal transcribed spacer. The alpha diversity indexes of gut mycobiota in R. bieti were significantly higher than R. roxellana and R. strykeri, the beta diversity indicated that R. roxellana and R. bieti had more similar feeding habits. Core mycobiota demonstrated commonalities among the three species and potentially associated with feeding habits. Mycobiota displaying significant differences exhibited the respective characteristics of the host, likely associated with the hosts' living environment. Among them, animal and plant pathogenic fungi and lichen parasites are potential threats to the survival of snub-nosed monkeys for their pathogenicity to both monkeys and their food plants. Functionally, fungal trophic modes and functional guilds revealed a strong association between gut mycobiota and host diet. We found a higher abundance and more significant correlations with lichen parasitic fungi in R. strykeri than the other two species, indicating potential threats to their foods. Accordingly, this study revealed the basic structures of gut mycobiota of three wild Rhinopithecus species and highlighted the associations between gut mycobiota and their feeding habits and living environments. Furthermore, due to the close connection between fungi and the environment, animals could ingest fungi from their diet; thus, we speculate that gut mycobiota may serve a role in environmental monitoring for wildlife.

摘要:

摘要: The Tibetan antelope (Pantholops hodgsonii), blue sheep (Pseudois nayaur), and Tibetan sheep (Ovis aries) are the dominant small ruminants in the Three-River-Source National Park (TRSNP). However, knowledge about the association between gut microbiota and host adaptability remains poorly understood. Herein, multi-omics sequencing approaches were employed to investigate the gut microbiota-mediated forage adaption in these ruminants. The results revealed that although wild ruminants (WR) of P. hodgsoni and P. nayaur were faced with severe foraging environments with significantly low vegetation coverage and nutrition, the apparent forage digestibility of dry matter, crude protein, and acid detergent fiber was significantly higher than that of O. aries. The 16s rRNA sequencing showed that the gut microbiota in WR underwent convergent evolution, and alpha diversity in these two groups was significantly higher than that in O. aries. Moreover, indicator species, including Bacteroidetes and Firmicutes, exhibited positive relationships with apparent forage digestibility, and their relative abundances were enriched in the gut of WR. Enterotype analysis further revealed that enterotype 1 belonged to WR, and the abundance of fatty acid synthesis metabolic pathway-related enzyme genes was significantly higher than enterotype 2, represented by O. aries. Besides, the metagenomic analysis identified 14 pathogenic bacterial species, among which 10 potentially pathogenic bacteria were significantly enriched in the gut microbiota of O. aries. Furthermore, the cellulolytic strains and genes encoding cellulase and hemicellulase were significantly enriched in WR. In conclusion, our results provide new evidence of gut microbiota to facilitate wildlife adaption in severe foraging environments of the TRSNP, China. This research reveals the gut microbiota-mediated severe foraging environment adaptation of wild small ruminants in the Three-River-Source National Park. Unlike Tibetan sheep (TS), blue sheep (PN and Tibetan antelope (TA) often grazed low-quality herbage in a wildness environment, and the higher microbial diversity and resilient network characteristics enabled the hosts to cope with flexible feeding environments. Environmental heterogeneity made the gut microbiota of PN and TA exhibit convergent evolutionary characteristics to adapt to nutritional stress from the habitats. Moreover, a study on microbial enterotypes revealed the two enterotypes, especially E1 exhibited by PN and TA, exhibit higher forage utilization potential and typical microorganisms involved in fatty acid and oxidative phosphorylation pathways play vital roles in energy production and maintaining the hosts' energy balance in the face of cold, anoxia, and food scarcity situation. Furthermore, the less abundant the microbial pathogens, the more abundant the forage-degrading microbiota, and the CAZymes genes encoding cellulose and hemicellulase enable wild small ruminants to better adapt to low quantity and poor-quality forage environments. image

摘要:

摘要: The small-island effect (SIE) has been used to quantify the increase of established non-native species richness with island area but has not yet been applied to explore the dynamics of non-native species abundance, which is important to develop timely mitigation strategies on established populations. Based on field surveys of established populations of the American bullfrog (Lithobates catesbeianus = Rana catesbeiana) across 92 permanent water bodies on 31 islands in the Zhoushan Archipelago, China, we explored the abundance-area relationship (AAR) of the invasive bullfrogs at the island and habitat (i.e., permanent still waters) scales, respectively. We did not detect the non-linear increase of bullfrog abundance with island area in the Zhoushan Archipelago, but found a piecewise trend of the bullfrog abundance with the area of invaded waters. Overall, bullfrogs were more abundant on larger islands, less isolated islands, and in waters with lower densities of native anurans. Our findings indicate that the invasive bullfrogs may have not reached the threshold of rapid increase of population abundance in the Zhoushan Archipelago and highlight the importance of continued close monitoring to prevent future population outbreaks.