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High-altitude conditions on the Tibetan Plateau are often depicted as an inhospitable environment for conventional farming, yet evidence shows that communities in western Tibet grew ecologically hardy crops such as 6-row barley (Hordeum vulgare) by at least the 1^stmillennium BCE, at locations above 4,000 meters above sea level (masl). However, little is known about the specific cultivation strategies and culinary traditions that these agropastoral communities developed. Stable carbon and nitrogen isotope compositions of grains inform growing conditions and provide much needed insight into the cultivation strategies in such a unique environment. We use δ¹³C and δ¹⁵N values of archaeologically recovered barley remains to investigate past watering and soil-management strategies. Our results infer high labor investment in manuring and watering in barley farming. This suggests an intensive cultivation system in Western Tibet, 1,000 BCE −1,000 CE, despite the high-altitude pastoral landscape. 

Inocybe is the largest genus in the family Inocybaceae, with approximately 1000 species worldwide. Basic data on the species diversity, geographic distribution, and the infrageneric framework of Inocybe are still incomplete because of the intricate nature of this genus, which includes numerous unrecognized taxa that exist around the world. A multigene phylogeny of the I. umbratica–paludinella group, initially designated as the “I. angustifolia subgroup”, was conducted using the ITS-28S-rpb2 nucleotide datasets. The seven species, I. alabamensis, I. angustifolia, I. argenteolutea, I. olivaceonigra, I. paludinella, I. subangustifolia, and I. umbratica, were confirmed as members of this species group. At the genus level, the I. umbratica–paludinella group is a sister to the lineage of the unifying I. castanea and an undescribed species. Inocybe sect. Umbraticae sect. nov. was proposed to accommodate species in the I. umbratica–paludinella group and the I. castanea lineage. This section now comprises eight documented species and nine new species from China, as described in this paper. Additionally, new geographical distributions of I. angustifolia and I. castanea in China are reported. The nine new species and I. angustifolia, I. castanea, I. olivaceonigra, and I. umbratica are described in detail and illustrated herein with color plates based on Chinese materials. A global key to 17 species in the section Umbraticae is provided. The results of the current study provide a more detailed basis for the accurate identification of species in the I. umbratica-paludinella group and a better understanding of their phylogenetic placement. 

Archaeological research demonstrates that an agropastoral economy was established in Tibet during the second millennium BC, aided by the cultivation of barley introduced from South-western Asia. The exact cultural contexts of the emergence and development of agropastoralism in Tibet, however, remain obscure. Recent excavations at the site of Bangga provide new evidence for settled agropastoralism in central Tibet, demonstrating a material divergence from earlier archaeological cultures, possibly corresponding to the intensification of agropastoralism in the first millennium BC. The authors’ results depict a more dynamic system of subsistence in the first millennium BC, as the populations moved readily between distinct economic modes and combined them in a variety of innovative ways. 

Abstract The interfollicular epidermis (IFE) forms a water-tight barrier that is often disrupted in inflammatory skin diseases. During homeostasis, the IFE is replenished by stem cells in the basal layer that differentiate as they migrate toward the skin surface. Conventionally, IFE differentiation is thought to be stepwise as reflected in sharp boundaries between its basal, spinous, granular and cornified layers. The transcription factor GRHL3 regulates IFE differentiation by transcriptionally activating terminal differentiation genes. Here we use single cell RNA-seq to show that murine IFE differentiation is best described as a single step gradualistic process with a large number of transition cells between the basal and spinous layer. RNA-velocity analysis identifies a commitment point that separates the plastic basal and transition cell state from unidirectionally differentiating cells. We also show that in addition to promoting IFE terminal differentiation, GRHL3 is essential for suppressing epidermal stem cell expansion and the emergence of an abnormal stem cell state by suppressing Wnt signaling in stem cells.