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The primary host of plague in the Qinghai-Tibet Plateau (QTP), China, is Marmota himalayana, which plays an essential role in the maintenance, transmission, and prevalence of plague. To achieve a more clear insight into the differentiation of M. himalayana, complete cytochrome b (cyt b) gene and 11 microsatellite loci were analyzed for a total of 423 individuals from 43 localities in the northeast of the QTP. Phylogenetic analyses with maximum likelihood and Bayesian inference methods showed that all derived haplotypes diverged into two primary well-supported monophyletic lineages, I and II, which corresponded to the referential sequences of two recognized subspecies, M. h. himalayana and M. h. robusta, respectively. The divergence between the two lineages was estimated to be at about 1.03 million years ago, nearly synchronously with the divergence between M. baibacina and M. kastschenkoi and much earlier than that between M. vancouverensis and M. caligata. Genetic structure analyses based on the microsatellite dataset detected significant admixture between the two lineages in the mixed region, which verified the intraspecies level of the differentiation between the two lineages. Our results for the first time demonstrated the coexistence of M. h. himalayana and M. h. robusta, and also, determined the distribution range of the two subspecies in the northeast of QTP. We provided fundamental information for more effective plague control in the QTP. [ABSTRACT FROM AUTHOR]

Simple Summary: The gut microbiota are crucial for hosts. For mammals, different gastrointestinal tract (GIT) segments have specific microbial communities, which play an essential role in the host's nutrition, metabolism, immunity, and health. Plateau zokors (Eospalax baileyi) and Gansu zokors (Eospalax cansus) are closely related species that belong to the Spalacidae family, and are common pests in agriculture, forestry, and animal husbandry in northwestern China, with a sympatric distribution area in the transition zone between the Qinghai-Tibetan Plateau and the Loess Plateau. Here, the characteristics of the microbiota communities in different GIT segments of the plateau zokor and the Gansu zokor were studied, and the microbiota communities of the two zokor species were compared. Our results provide important information for further study on the function of microbiota communities in different GIT segments and the potential use of the gut microbiota as a new method for the population management of the zokors. In this study, based on high-throughput sequencing technology, the biodiversity and the community structure of microbiota in different GIT segments (the stomach, small intestine, cecum and rectum) of plateau zokors and Gansu zokors were studied and compared. A source tracking analysis for the microbial communities of different GIT segments was carried out using the fast expectation–maximization microbial source tracking (FEAST) method. We found that, for both species, the microbial community richness and diversity of the small intestine were almost the lowest while those of the cecum were the highest among the four segments of the GIT. Beta diversity analyses revealed that the bacterial community structures of different GIT segments were significantly different. As for the comparison between species, the bacterial community compositions of the whole GIT, as well as for each segment, were all significantly different. Source tracking conducted on both zokors indicated that the soil has little effect on the bacterial community of the GIT. A fairly high percentage of rectum source for the bacterial community of the stomach indicated that both zokors may engage in coprophagy. [ABSTRACT FROM AUTHOR]

Wild-caught animals must cope with drastic lifestyle and dietary changes after being induced to captivity. How the gut microbiome structure of these animals will change in response receives increasing attention. The plateau zokor (Eospalax baileyi), a typic subterranean rodent endemic to the Qinghai-Tibet plateau, spends almost the whole life underground and is well adapted to the environmental pressures of both plateau and underground. However, how the gut microbiome of the plateau zokor will change in response to captivity has not been reported to date. This study compared the microbial community structure and functions of 22 plateau zokors before (the WS group) and after being kept in captivity for 15 days (the LS group, fed on carrots) using the 16S rRNA gene via high-throughput sequencing technology. The results showed that the LS group retained 973 of the 977 operational taxonomic units (OTUs) in the WS group, and no new OTUs were found in the LS group. The dominant bacterial phyla were Bacteroides and Firmicutes in both groups. In alpha diversity analysis, the Shannon, Sobs, and ACE indexes of the LS group were significantly lower than those of the WS group. A remarkable difference (P < 0.01) between groups was also detected in beta diversity analysis. The UPGMA clustering, NMDS, PCoA, and Anosim results all showed that the intergroup difference was significantly greater than the intragroup difference. And compared with the WS group, the intragroup difference of the gut microbiota in the LS group was much larger, which failed to support the assumption that similar diets should drive convergence of gut microbial communities. PICRUSt revealed that although some functional categories displayed significant differences between groups, the relative abundances of these categories were very close in both groups. Based on all the results, we conclude that as plateau zokors enter captivity for a short time, although the relative abundances of different gut microbiota categories shifted significantly, they can maintain almost all the OTUs and the functions of the gut microbiota in the wild. So, the use of wild-caught plateau zokors in gut microbial studies is acceptable if the time in captivity is short. [ABSTRACT FROM AUTHOR]

Bumblebees show a series of advantages over other pollinating insects in offering pollination services for both the ecosystem and agricultural production, especially in high‐altitude areas. With climate warming, their diversity at high altitudes will be threatened. Therefore, more attention should be paid to the management of bumblebee resources at high altitudes to prevent their decline here. Discovering drivers responsible for the spatial variation of biodiversity is a benefit for developing appropriate management.Here, based on the bumblebee diversity on three plateau areas with an altitude gradient, the roles of different environmental factors, the climate, land cover, topography, habitat heterogeneity and soil, in the bumblebee composition were assessed by generalised dissimilarity modelling. And the relative importance of variables was evaluated by the impact on the magnitude of total biological change and the per cent change in deviance explained by models.According to the results, in the low‐altitude area, the climate played a vital role and the most important variable was the climate variable. Then, with the altitude rising, the effect of land cover continually increased. In the medium‐altitude area, the effects of different factors were detected to be similar, and the most important variables were a climate variable and a land cover variable. In the high‐altitude area, land cover finally replaced the climate as the most important factor, and one land cover variable was assessed as the most important variable. Our study revealed that the relative importance of different environmental factors on the biodiversity of bumblebees can differ as the altitude rises. [ABSTRACT FROM AUTHOR]

Climate warming threatens dozens of bumblebee species across the world, including alpine areas. In plateaus with vast and continuous high-altitude areas, bumblebees' response to climate warming may be relatively optimistic. To study the species' responses to future climate in the Qinghai–Tibet Plateau, we quantified the suitable areas for 4 local bumblebee indicator species under current and future climate scenarios (Shared Socio-economic Pathway 126, 245, 370, and 585 in 2,100) using MaxEnt models. Suitable areas of indicator species were stacked to obtain the species richness layer. According to the acreage and connectivity of suitable areas and the acreage of the high richness area, a warmed climate will be more suitable for bumblebees' distribution compared to the current climate. The SSP 126 and SSP 245 scenario will be the 2 most suitable. Meanwhile, with climate warming, suitable areas and the high richness areas will move to high altitudes and their altitude range will decrease. The greater suitability in warmed climates may be caused by the topography of plateaus, which provides an opportunity for bumblebees to migrate to cooler areas. However, mitigation of warming is still necessary because an excessively warm climate will decrease bumblebees' habitat suitability. In plateaus, species in lower altitudes will migrate to higher altitudes, conservation in high altitudes should pay attention to not only original species, but also immigrated species. In lower altitudes, many species will migrate to higher altitudes, then local bumblebee diversity will decrease. Local conservation should be focused on these lower altitude areas. [ABSTRACT FROM AUTHOR]

Simple Summary: Determining the adaptive mechanisms by which bumblebees adapt to high altitudes can help us to better understand their distribution, providing a basis for the future protection and utilization of bumblebee resources. For this study, the adaptive mechanisms of two dominant bumblebee species in the northeastern Qinghai-Tibet Plateau—Bombus kashmirensis and B. waltoni—were studied through transcriptomics methods. For each species, enrichment analysis of the differentially expressed genes and gene set enrichment analysis were carried out between samples collected at different altitudes (4000 m, 4500 m, and 5000 m). The results indicate that these bumblebees tend to up-regulate energy metabolism-related genes when facing extremely high-altitude environments. Of the enriched pathways up-regulated in higher altitudes, the pentose and glucuronate interconversions pathway presented the most severe up-regulation in multiple comparisons of different altitudes for B. kashmirensis, as well as the AMPK signaling pathway, which was found to be up-regulated in both species. Notably, limited by the extreme high altitudes in this study, oxidative phosphorylation was found to be down-regulated with increasing altitude, which is uncommon in studies on bumblebee adaptation to high altitudes. Determining the adaptive mechanisms by which bumblebees adapt to high altitudes can help us to better understand their distribution, providing a basis for the future protection and utilization of bumblebee resources. For this study, the adaptive mechanisms of two dominant bumblebee species in the northeastern Qinghai-Tibet Plateau—Bombus kashmirensis and B. waltoni—were studied through transcriptomics methods. For each species, enrichment analysis of the differentially expressed genes and gene set enrichment analysis were carried out between samples collected at different altitudes (4000 m, 4500 m, and 5000 m). The results indicate that these bumblebees tend to up-regulate energy metabolism-related genes when facing extremely high-altitude environments. Of the enriched pathways up-regulated in higher altitudes, the pentose and glucuronate interconversions pathway presented the most severe up-regulation in multiple comparisons of different altitudes for B. kashmirensis, as well as the AMPK signaling pathway, which was found to be up-regulated in both species. Notably, limited by the extreme hypoxic conditions in this study, oxidative phosphorylation was found to be down-regulated with increasing altitude, which is uncommon in studies on bumblebee adaptation to high altitudes. [ABSTRACT FROM AUTHOR]

Geographical barriers and distance can reduce gene exchange among animals, resulting in genetic divergence of geographically isolated populations. The Tibetan antelope (Pantholops hodgsonii) has a geographical range of approximately 1600 km across the Qinghai–Tibet Plateau, which comprises a series of tall mountains and big rivers. However, previous studies indicate that there is little genetic differentiation among their geographically delineated populations. To better understand the genetic structure of P. hodgsonii populations, we collected 145 samples from the 3 major calving regions, taking into consideration their various calving grounds and migration routes. We used a combination of mitochondrial sequences (Cyt b, ATPase, D‐loop and COX I) to investigate the genetic structure and the evolutionary divergence of the populations. Significant, albeit weak, genetic differentiation was detected among the 3 geographical populations. Analysis of the genetic divergence process revealed that the animals gradually entered a period of rapid genetic differentiation approximately 60 000 years ago. The calving migration of P. hodgsonii cannot be the main cause of their weak genetic structure because this cannot fully homogenize the genetic pool. Instead, the geological and climatic events as well as the coupling vegetation succession process during this period have been suggested to greatly contribute to the genetic structure and the expansion of genetic diversity. [ABSTRACT FROM AUTHOR]

Research on corrosion of archaeological porcelain glaze has rarely been carried out in the past, although corrosion damage precious heritage items continuously. A group of black-glazed porcelains from the Song Dynasty was excavated at a poor conservation site in Chongqing, and one of their fragments was investigated with optical microscope, SEM-EDX, FTIR and Raman spectroscopy. The results showed that the alteration crust of the glaze mainly consisted of silica-rich gel and contained a variety of heterogeneous phases, including the liquid phase separation structure and different crystals. The crystals mainly include hematite, magnetite, rutile, pseudobrookite and silicon dioxide. The inter-diffusion reaction between alkalis in glaze and hydrogenated species in contact solution was the main reaction, which led to the formation of silicon-rich hydrate layers. The amorphous layers eventually transformed into acicular silica crystals under long exposure to environment. • Alteration in underground environment of ancient Chinese black-glazed porcelains. • The complex structures of black glaze have a special effect on its alteration process. • The first discovery of acicular silica crystals on alteration crust. • Refining corrosion mechanisms of underground black glaze. [ABSTRACT FROM AUTHOR]