摘要: Asymmetric competition occurs when some species have distinct advantages over their competitors and is common in animals with overlapping habitats and diet. However, the mechanism allowing coexistence between asymmetric competitors is not fully clear. Chinese white-bellied rats (Niviventer confucianus, CWR) and Korean field mice (Apodemus peninsulae, KFM) are common asymmetric competitors in shrublands and forests west of Beijing city. They share similar diet (e.g. plant seeds) and activity (nocturnal), but differ in body size (CWR are bigger than KFM), food hoarding habit (CWR: mainly larder hoarding; KFM: both larder and scatter hoarding), and ability to protect cached food (CWR are more aggressive than KFM). Here, we tested seed competition in 15 CWR-KFM pairs over a 10-day period under semi-natural enclosure conditions to uncover the differences in food hoarding, cache pilferage, and food protection between the 2 rodents, and discuss the implication for coexistence. Prior to pilferage, CWR harvested and ate more seeds than KFM. CWR tended to larder hoard seeds, whereas KFM preferred to scatter hoard seeds. Following pilferage, CWR increased consumption, decreased intensity of hoarding, and pilfered more caches from KFM than they lost, while KFM increased consumption more than they hoarded, and they preferred to hoard seeds in low and medium competition areas. Accordingly, both of the 2 rodent species increased their total energy consumption and hoarding following pilferage. Both rodent species tended to harvest seeds from the source, rather than pilfer caches from each other to compensate for cache loss via pilferage. Compared to CWR, KFM consumed fewer seeds when considering seed number, but hoarded more seeds when considering the seeds' relative energy (energy of hoarded seeds/rodent body mass(2/3)) at the end of the trials. These results suggest that asymmetric competition for food exists between CWR and KFM, but differentiation in hoarding behavior could help the subordinate species (i.e. KFM) hoard more energy than the dominant species (i.e. CWR), and may contribute to their coexistence in the field.

摘要: The genes of the major histocompatibility complex (MHC) encode cell surface proteins that are essential for adaptive immunity. MHC genes show the most prominent genetic diversity in vertebrates, reflecting the adaptation of populations to their evolving environment, population survival and reproduction. In the present study, we used next -generation sequencing (NGS) to study the loci polymorphism of exon 3 of the MHC class I genes in an ovoviviparous skink, the many-lined sun skink, Eutropis multifasciata and five other species of Scincidae, to quantify genetic variation. In addition, we genotyped the same MHC class I genes of E. multifasciata using clone sequencing, to directly compare the effectiveness of both analytical techniques for MHC genotyping. NGS detected 20 MHC class I alleles in E. multifasciata, and 2 to 15 alleles in the other five Scincidae species. However, clone sequencing detected only 15 of those MHC class I alleles in E. multifasciata. In addition, trans -species polymorphism of MHC class I genes was studied by constructing a phylogenetic tree using the gene sequences obtained by NGS. Phylogenetic analysis revealed that MHC class I alleles were shared among different species of Scincidae with trans-species polymorphism, and did not exhibit specific genealogical inheritance. These results have important implications for understanding polymorphism interspecies diversity in the MHC genes of Scincidae, and the evolution of the MHC more broadly.

摘要: Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice. We examined the spatial distribution and habitat preference of four Diploderma species (Diploderma drukdaypo, D. laeviventre, D. batangense, and D. vela), which are endemic to the Qinghai-Tibet Plateau and are currently under state protection. We used the ensembles of small models (ESM) approach and predicted potential distribution ranges of the species in current and two future climate scenarios (SSP126 and SSP585). The degree of overlap between the predicted distribution ranges and existing natural reserves was further analyzed. Habitat preference was examined using a paired quadrat method. Our results predicted that D. drukdaypo has a current distribution range of 600 km2, which would decrease to 50 km2 and 55 km2 under the SSP126 and SSP585 respectively. For D. laeviventre, the current distribution range is 817 km2, with minimum changes in the two future climate scenarios (774 km2 and 902 km2). For D. batangense, the current distribution range is 875 km2, which would expand to 1 522 km2 and 3 340 km2 in the two future climate scenarios. Similarly for D. vela, the current distribution range is 1 369 km2, which would change to 1 825 km2 and 2 043 km2 respectively under the two future climate scenarios. The effect of protection of current nature reserves are likely low for those species; we found no overlap (D. drukdaypo, D. laeviventre) or little overlap (D. batangense 2.04%-3.56%, D. vela 15.52%-16.87%) between the currently designated protection area and distribution range under current and future climate scenarios. For habitat preference, stones appear to be the critical habitat element for those species although different species had different stone requirements. Taken together, we provided critical information on potential distribution ranges and habitat preference for four endangered Diploderma species, and confirmed the inadequacy of current nature reserves. The establishment of new or expansion of existing nature reserves is urgent for the conservation of those species.

摘要: Many animals migrate during the breeding season. It is important to study the patterns of breeding migration of wild animals, especially rare and endangered species. However, current data acquisition methods are too coarse and imprecise for investigating the circadian rhythms of migrations in amphibians. Based on the frustrated total reflection image (FTRI), we developed a new device and recorded the precise migration time of an endangered salamander, Liangshantriton taliangensis. During the breeding period, a total of 33 individuals were effectively recorded. Analysis of the data indicated that the circadian rhythm of breeding migration in L. taliangensis was bimodal, and migration mainly occurred from 05:00 to 13:00 (81.82% of the total migration records). The average relative activity intensity index (RAI) of breeding migration peaked in the temperature range of 14.0-16.0 degrees C. With increased average relative air humidity, the activity intensity first increased and then decreased, reaching a peak in the humidity range of 91.0%-97.0%. These results demonstrate that our new device is a viable and accurate method for recording the migration time of target species. It is important to reveal the breeding migration pattern of L. taliangensis, which is important for the conservation of this species. Meanwhile, this new device can be used for field monitoring and conservation studies of amphibians, reptiles and other animals.

摘要: Taxonomic studies of the Odorrana versabilis group have been consistently disorganized, and they have often been incorrectly associated with an abandoned subgenus or genus Bamburana in existing literature. In this study, we conducted an integrative taxonomic analysis using molecular phylogenetic analysis of two mitochondrial gene fragments (16S rRNA and CO1) and morphological examination of 41 specimens collected during herpetological surveys in southern China. Our results confirmed the monophyly of O. versabilis group which exhibited distinct morphological traits. We also identified a cryptic lineage sister with O. exiliversabilis. Additionally, our study revealed that O. trankieni was nested within O. nasuta. Consequently, we redefined the morphological characteristics of the O. versabilis group, described a new species in this group, O. confusa sp. nov., and proposed that O. trankieni be considered a junior synonym of O. nasuta. One of the most significant findings of this study was the observation of distinct morphological changes in adult males across all species within the O. versabilis group between the non-breeding and breeding seasons. This study contributes to research on various aspects of Asian amphibian fauna, including taxonomy, ecology, evolution, and physiology.