Bacterial microbiome and their assembly processing in two sympatric desert rodents ( and ) from different geographic sources.

The microbiome of mammals has profound effects on host fitness, but the process, which drives the assembly and shift of mammalian microbiome remains poorly understood. To explore the patterns of small mammal microbial communities across host species and geographical sites and measure the relative contributions of different processes in driving assembly patterns, 2 sympatric desert rodent species ( and ) were sampled from 2 geographically distant regions, which differed in the environment, followed by 16S rRNA gene sequencing. The microbiomes differed significantly between and , and linear mixed modeling (LMM) analysis revealed that microbial diversity was mostly affected by species rather than the environment.

Evolutionary factors and habitat filtering affect the pattern of Gerbillinae diversity.

How ecological and evolutionary factors affect small mammal diversity in arid regions remains largely unknown. Here, we combined the largest phylogeny and occurrence dataset of Gerbillinae desert rodents to explore the underlying factors shaping present-day distribution patterns. In particular, we analyzed the relative contributions of ecological and evolutionary factors on their species diversity using a variety of models.

De novo genome of thick-tailed pygmy jerboa Salpingotus crassicauda, Cardiocraniinae, Dipodidae.

Pygmy jerboas are one of the smallest taxa of rodents. They exhibit distinctly different morphological and biological characteristics from other subfamilies, such as more restricted distribution, species richness, reproductive ability, and population size. Agricultural expansion and the development of new energy projects in recent years lead to sharp decline of their natural populations.

Comparative transcriptome analysis reveals candidate genes related to the sex differentiation of Schisandra chinensis.

Schisandra chinensis is a monoecious plant with unisex flowers. The fruit of S. chinensis is of high medical with economic value.

Whole-genome sequencing reveals adaptations of hairy-footed jerboas (Dipus, Dipodidae) to diverse desert environments.

Background: Environmental conditions vary among deserts across the world, spanning from hyper-arid to high-elevation deserts. However, prior genomic studies on desert adaptation have focused on desert and non-desert comparisons overlooking the complexity of conditions within deserts. Focusing on the adaptation mechanisms to diverse desert environments will advance our understanding of how species adapt to extreme desert environments.

Similar adaptative mechanism but divergent demographic history of four sympatric desert rodents in Eurasian inland.

Phenotypes associated with metabolism and water retention are thought to be key to the adaptation of desert species. However, knowledge on the genetic changes and selective regimes on the similar and divergent ways to desert adaptation in sympatric and phylogenetically close desert organisms remains limited. Here, we generate a chromosome level genome assembly for Northern three-toed jerboa (Dipus sagitta) and three other high-quality genome assemblies for Siberian jerboa (Orientallactaga sibirica), Midday jird (Meriones meridianus), and Desert hamster (Phodopus roborovskii).

Genomic Consequences of and Demographic Response to Pervasive Hybridization Over Time in Climate-Sensitive Pikas.

Rare and geographically restricted species may be vulnerable to genetic effects from inbreeding depression in small populations or from genetic swamping through hybridization with common species, but a third possibility is that selective gene flow can restore fitness (genetic rescue). Climate-sensitive pikas (Ochotona spp.) of the Qinghai-Tibetan Plateau (QHTP) and its vicinity have been reduced to residual populations through the movement of climatic zones during the Pleistocene and recent anthropogenic disturbance, whereas the plateau pika (O.

Transcriptome analysis of pika heart tissue reveals mechanisms underlying the adaptation of a keystone species on the roof of the world.

High-altitude environments impose intense stresses on living organisms and drive striking phenotypic and genetic adaptations, such as hypoxia resistance, cold tolerance, and increases in metabolic capacity and body mass. As one of the most successful and dominant mammals on the Qinghai-Tibetan Plateau (QHTP), the plateau pika () has adapted to the extreme environments of the highest altitudes of this region and exhibits tolerance to cold and hypoxia, in contrast to closely related species that inhabit the peripheral alpine bush or forests. To explore the potential genetic mechanisms underlying the adaptation of to a high-altitude environment, we sequenced the heart tissue transcriptomes of adult plateau pikas (comparing specimens from sites at two different altitudes) and Gansu pikas (.

Mammalian diversification bursts and biotic turnovers are synchronous with Cenozoic geoclimatic events in Asia.

Asia's rich species diversity has been linked to its Cenozoic geodiversity, including active mountain building and dramatic climatic changes. However, prior studies on the diversification and assembly of Asian faunas have been derived mainly from analyses at taxonomic or geographic scales too limited to offer a comprehensive view of this complex region's biotic evolution. Here, using the class Mammalia, we built historical biogeographic models drawn on phylogenies of 1,543 species occurring across Asia to investigate how and when the mammal diversity in Asian regions and mountain hotspots was assembled.

Environmental drivers of sympatric mammalian species compositional turnover in giant panda nature reserves: Implications for conservation.

The charismatic giant panda (Ailuropoda melanoleuca) is an iconic species of wildlife conservation worldwide. As the most effective measure to protect giant pandas and their habitats, China has established 67 giant panda nature reserves (GPNR) during the last five decades, which also bring benefits to many sympatric medium- and large-bodied mammals (MLM). To better inform the planning of the GPNR network with the view of preserving regional MLM diversity, we investigated the zeta diversity (a novel index to measure species compositional turnover considering the contributions of both rare and common species) patterns (i.

Ring distribution patterns-diversification or speciation? Comparative phylogeography of two small mammals in the mountains surrounding the Sichuan Basin.

Studying the genetic differentiation in a unique geographical area contributes to understanding the process of speciation. Here, we explore the spatial genetic structure and underlying formation mechanism of two congeneric small mammal species (Apodemus draco and A. chevrieri), which are mainly distributed in the mountains surrounding the lowland Sichuan Basin, southwest China.

Elevation patterns and critical environmental drivers of the taxonomic, functional, and phylogenetic diversity of small mammals in a karst mountain area.

Understanding how biodiversity components are related under different environmental factors is a fundamental challenge for ecology studies, yet there is little knowledge of this interplay among the biotas, especially small mammals, in karst mountain areas. Here, we examine the elevation patterns of the taxonomic diversity (TD), phylogenetic diversity (PD), and functional diversity (FD) of small mammals in a karst mountain area, the Wuling Mountains, Southwest China, and compare these patterns between taxa (Rodentia and Eulipotyphla) and scales (broad- and narrow-range species). We also disentangle the impacts of the human influence index, net primary productivity (NPP), normalized difference vegetation index (NDVI), annual precipitation (AP), and annual mean temperature (AMT) on these three facets of biodiversity by using structural equation modeling.

Divergent selection along elevational gradients promotes genetic and phenotypic disparities among small mammal populations.

Species distributed along mountain slopes, facing contrasting habitats in short geographic scale, are of particular interest to test how ecologically based divergent selection promotes phenotypic and genetic disparities as well as to assess isolation-by-environment mechanisms. Here, we conduct the first broad comparative study of phenotypic variation along elevational gradients, integrating a large array of ecological predictors and disentangling population genetic driver processes. The skull form of nine ecologically distinct species distributed over a large altitudinal range (100-4200 m) was compared to assess whether phenotypic divergence is a common phenomenon in small mammals and whether it shows parallel patterns.

Phylogeography and ecological niche modeling unravel the evolutionary history of the Yarkand hare, Lepus yarkandensis (Mammalia: Leporidae), through the Quaternary.

Background: The Taklimakan Desert in China is characterized by unique geological and historical dynamics and endemic flora and fauna, but the influence of historical climate oscillations on the evolutionary history of endemic animals is poorly understood. Lepus yarkandensis is an oases-dependent Near Threatened species that lives in fragmented oasis habitats in the Taklimakan Desert, China. We investigated the geological and climatic impacts on its geographical differentiation, demographic history and influence of Pleistocene glacial-interglacial cycles on the evolutionary history of L.

Disjunct distribution and distinct intraspecific diversification of Eothenomys melanogaster in South China.

Background: South China encompasses complex and diverse landforms, giving rise to high biological diversity and endemism from the Hengduan Mountains to Taiwan Island. Many species are widely distributed across South China with similar disjunct distribution patterns. To explore the causes of these disjunct distribution patterns and their genetic consequences, we investigated the endemic species Père David's Chinese Vole (Eothenomys melanogaster) by integrating geological and ecological factors.

The roles of environment, space, and phylogeny in determining functional dispersion of rodents (Rodentia) in the Hengduan Mountains, China.

The recently described trait-based approach is becoming widely popular for a mechanistic understanding of species coexistence. However, the greatest challenge in functional analyses is decomposing the contributions of different ecological and evolutionary processes (e.g.

Heterogeneous distributional responses to climate warming: evidence from rodents along a subtropical elevational gradient.

Background: Understanding whether species' elevational range is shifting in response to directional changes in climate and whether there is a predictable pattern in that response is one of the major challenges in ecology. However, so far very little is known about the distributional responses of subtropical species to climate change, especially for small mammals. In this study, we examined the elevational range shifts at three range points (upper and lower range limits and abundance-weighted range centre) of rodents over a 30-year period (1986 to 2014-2015), in a subtropical forest of Southwest China.

An endemic rat species complex is evidence of moderate environmental changes in the terrestrial biodiversity centre of China through the late Quaternary.

The underlying mechanisms that allow the Hengduan Mountains (HDM), the terrestrial biodiversity centre of China, to harbour high levels of species diversity remain poorly understood. Here, we sought to explore the biogeographic history of the endemic rat, Niviventer andersoni species complex (NASC), and to understand the long-term persistence of high species diversity in this region. In contrast to previous studies that have proposed regional refuges in eastern or southern of the HDM and emphasized the influence of climatic oscillations on local vertebrates, we found that HDM as a whole acted as refuge for the NASC and that the historical range shifts of NASC mainly occurred in the marginal regions.

[Vestibulotomy about the displaced facial nerve].

Objective: To investigate the feasibility of vestibulotomy above the displaced facial nerve.

Methods: From January 2000 to January 2002, eight patients with severe congenital conductive hearing loss underwent the vestibulotomy above displaced facial nerve and reconstruction of the ossicular chain with a total ossicular replacement prosthesis, which all for the congenital middle ear deformity and the facial nerve overhang and concealed the oval window niche or lied inferior to the oval window. In four of eight cases, the facial nerve was transposed in order to access the oval window niche.