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Recycling of molybdenum isotopes in continental subduction zones remains debated. In this contribution, we re‐visit the Mo isotope compositions of the Sailipu post‐collisional ultrapotassic rocks in the Himalaya‐southern Tibet orogen. These ultrapotassic rocks have very varying δ98/95Mo values of −0.66 to −0.07‰ and Mo/Ce ratios of 0.0008–0.005, which are lower than those of mid‐ocean ridge basalts (MORB; δ98/95Mo = −0.20 ± 0.06‰, and Mo/Ce = 0.03) and oceanic subduction‐related (i.e., mantle source involving fluids, residual slab, or oceanic sediments) magmatic rocks (e.g., modern arc lavas, Cenozoic OIB‐type basalts in eastern China and the central Mariana Trough basalts in the back‐arc basin, syn‐collisional andesitic rocks in southern Tibet). Combined with the light Mo isotopes of the Himalayan schists and gneisses, we suggest that the light Mo isotopic signature of the Sailipu ultrapotassic rocks is derived from subducted Indian continental crust. This is consistent with the extremely low δ11B (−17.4 to −9.7‰) and B/Nb (0.16–1) values and enriched Sr‐Nd‐Pb isotopes of the Sailipu ultrapotassic rocks. Thus, this study reveals the recycling of light Mo‐B isotopes during continental subduction and demonstrates that Mo‐B isotopes can effectively distinguish between continental and oceanic subduction. Plain Language Summary: Mo isotope systematics have been widely applied in the study of tracing recycled crustal materials, and abundant researches have proposed that heavy Mo isotopic compositions of arc‐mafic magma can be ascribed to slab‐dehydrated fluids. However, in continental subduction zones, the origin of the light Mo isotopes of post‐collisional mafic rocks (oceanic sediments during prior oceanic subduction vs. subducted continental crust) remains controversial, hindering our understanding of the recycling of continental crustal materials. In this study, we report new Mo isotope data of post‐collisional ultrapotassic rocks in the Lhasa block of the southern Tibetan plateau. We have used Mo isotope data along with B‐Sr‐Nd‐Pb isotopes of these ultrapotassic rocks, in combination with Mo‐B‐Sr‐Nd‐Pb isotopes of the Himalayan crustal rocks (e.g., gneisses and schists) to trace the crustal components in the post‐collisional mantle beneath southern Tibet. We concluded that the light Mo and B isotope compositions in southern Tibet were derived from subducted Indian continental crust rather than Neo‐Tethyan oceanic sediments. Thus, this study not only reveals the recycling of light Mo‐B isotopes in this typical collision orogen (i.e., Himalaya‐Tibet orogen) but also shows the potential in discriminating between oceanic subduction metasomatism and continental subduction metasomatism. Key Points: Post‐collisional ultrapotassic rocks in southern Tibet have extremely light Mo and B isotope compositionsThese light Mo‐B isotope features are derived from subducted Indian continental crustMo‐B isotopes have the potential to discriminate between oceanic and continental subduction [ABSTRACT FROM AUTHOR]

We report the sequencing at 131× coverage, de novo assembly and analyses of the genome of a female Tibetan wild boar. We also resequenced the whole genomes of 30 Tibetan wild boars from six major distributed locations and 18 geographically related pigs in China. We characterized genetic diversity, population structure and patterns of evolution. We searched for genomic regions under selection, which includes genes that are involved in hypoxia, olfaction, energy metabolism and drug response. Comparing the genome of Tibetan wild boar with those of neighboring Chinese domestic pigs further showed the impact of thousands of years of artificial selection and different signatures of selection in wild boar and domestic pig. We also report genetic adaptations in Tibetan wild boar that are associated with high altitudes and characterize the genetic basis of increased salivation in domestic pig. [ABSTRACT FROM AUTHOR]

The taxonomic history of the Amphiesma sensu lato has long been confused, and this complex was recently divided into three genera, i.e., Amphiesma Duméril, Bibron, and Duméril, 1854 sensu stricto, Hebius Thompson, 1913, and Herpetoreas Günther, 1860. Being the least known genus, Herpetoreas is reviewed herein through an integrative taxonomic approach. Our results indicate that specimens previously referred to Hebius parallelus (Boulenger, 1890) from Mêdog, Tibet, China, represent a new species. We describe here this new species and refer it to the genus Herpetoreas; therefore, we remove Hebius parallelus from the Chinese herpetofauna. A diagnostic key to all the species of Herpetoreas is also provided. Furthermore, we re-evaluate the diagnostic characters of the three genera formerly confused with Amphiesma, namely, Amphiesma, Hebius, and Herpetoreas. We provide a key to these three morphologically similar genera. We also emphasize the importance of the maxillary teeth and hemipenial morphology in the generic diagnosis in the family Natricidae. [ABSTRACT FROM AUTHOR]

• Anatectic granitic melt records Sr–Nd isotopic disequilibrium. • B–Mo isotopic variations in two-mica granites were controlled by dissolution of different mineral phases in the source. • B–Mo isotopic variations in muscovite leucogranites highlight the likely role of crystal–melt fractionation and melt–fluid interaction. • Both melting processes in the source and emplacement-level crystal–liquid separation control the compositional diversity of anatectic melts. Partial melts derived from crustal anatexis exhibit large variations in field characteristics, composition, and isotope geochemistry. The relative influence of melting process and magmatic differentiation on such heterogeneity is a subject of ongoing debate. Boron and molybdeum isotopes have the potential to shed light on the genesis of crustal melts, but the behaviors of B and Mo isotopes during crustal anatexis and differentiation are unclear. Here, we present geochemical and isotopic data, including whole-rock Sr–Nd–B–Mo and mineral B–Mo data, for the Conadong leucogranites in the Himalayan Block, to provide new insights into these issues. The studied samples include two-mica granites (biotite + muscovite), muscovite leucogranites (muscovite ± garnet), and biotite-rich granites. The two-mica granites were derived from muscovite dehydration melting of metasedimentary rocks. Their initial Sr and Nd isotopic compositions show positive correlation, implying non-modal partial melting associated with dissolution of accessory phases. The B contents (3.44–21.2 ppm) of the two-mica granites decrease but their δ11B (−15.80‰ to −13.25‰) and δ98Mo (−0.15‰ to 0.34‰) values increase with increasing Sr and Ba contents. This may have been controlled by different phases involved in non-modal melting (i.e., muscovite and feldspar). The muscovite leucogranites display features of residual liquids. Their δ11B (−15.38‰ to −11.90‰) and δ98Mo (−0.15‰ to 0.17‰) values negatively correlate with Sr and Ba contents, which can be ascribed to shallow-crustal crystal–liquid separation and melt–fluid interaction. The biotite-rich granites are least evolved, with large variations in their initial Sr–Nd isotopic compositions. They show relatively heavy whole-rock B isotopic compositions of −11.97‰ to −9.00‰. These may indicate that biotite-rich granites may be contaminated by entrained restitic minerals (e.g., biotite, feldspar and accessory minerals). Overall, this study demonstrates that compositional diversity of anatectic melts is controlled primarily by melting processes in the source and secondarily by emplacement-level crystal–liquid separation. Both non-modal partial melting and crystal–liquid separation could result in B–Mo isotopic fractionation in anatectic melts. [ABSTRACT FROM AUTHOR]

Identification of possible factors that affect Li-mineralizing potential is important to the understanding of the genesis of Li pegmatites. This study provides a comprehensive characterization of the recently discovered Bailongshan Li pegmatite district based on geochronological, petrological, mineralogical, thermal modeling, and Li isotopic data. Columbite-(Fe) U–Pb dating of two pegmatite dikes indicates they were emplaced at 212.3 ± 0.9 and 213.9 ± 0.7 Ma. The spodumene-absent pegmatite dikes yield substantially higher δ7Li values (+2.0‰ to +4.9‰) than spodumene-bearing dikes (−1.9‰ to +0.8‰). Modeling of Li isotopic fractionation during fractional crystallization, fluid exsolution, and diffusion after pegmatite emplacement indicates that the lighter Li isotopic compositions of spodumene-bearing pegmatites are attributable to fluid exsolution or diffusion-driven fractionation of short duration, whereas the heavier isotopic compositions of spodumene-absent pegmatites can be attributed to longer-duration, diffusion-driven fractionation. Together with the results of thermal modeling, we suggest that the cooling rate of pegmatite dikes was an important factor controlling the Li isotopic compositions of pegmatites and slower cooling caused heavier Li isotopic compositions. It may have important implications for the ore-forming potential of Li in pegmatites that high cooling rate is beneficial for forming Li pegmatites. [ABSTRACT FROM AUTHOR]