Landscape genomics analysis provides insights into future climate change-driven risk in rhesus macaque

The phylogenetic relationship and demographic history of rhesus macaques (Macaca mulatta) in subtropical and temperate regions, China

Pleistocene climatic oscillations exerted significant influences on the genetic structure and demography of rhesus macaque (Macaca mulatta) in eastern China. However, the evolutionary history of rhesus macaques in subtropical and temperate China remained unclear and/or controversial. Herein, we analyzed the autosomes, mitochondrial genomes, and Y-chromosomes from 84 individuals of Chinese rhesus macaque. The results revealed that (1) all individuals were clustered into pan-west and pan-east genetic groups, which exhibited Shaanxi Province as the northernmost region of western dispersal route of rhesus macaques in China; (2) in subtropical and temperate China, rhesus macaques were divided into four lineages (TH, DB, HS, and QL), and their divergence times corresponded to the Penultimate Glaciation (300-130 kya) and Last Glaciation (70-10 kya), respectively; (3) the individuals from Mt. Taihangshan (TH) are closely related to individuals from Mt. Dabashan (DB) in the autosomal tree, rather than individuals from Mt. Huangshan (HS) as indicated by the mitogenome tree, which supports the hypothesis that the ancestral rhesus macaques radiated into Mt. Taihangshan from Mt. Huangshan via Mt. Dabashan; and (4) the demographic scenario of the four lineages showed the ancestral rhesus macaques bottleneck and expansion corresponding to the suitable habitat reduction and expansion, which confirmed they had experienced northward recolonization and southward retreat events from Mt. Huangshan area via Northern China Plain to Northernmost China along with Pleistocene glacial cycles. This study provides a new insight into understanding how Pleistocene glaciation has influenced faunal diversity in subtropical and temperate China, especially for those exhibiting differential patterns of sex dispersal.

DNA metabarcoding reveals the seasonal variation of dietary composition of Taihangshan macaque (Macaca mulatta tcheliensis), Jiyuan, north China

Dietary analysis in wildlife is fundamental for understanding their flexible response to seasonal changes and developing effective conservation management measures. Taihangshan macaque (Macaca mulatta tcheliensis) is the northernmost population of rhesus macaque, currently only distributed in the southern Mt. Taihangshan area. This area belongs to a semi-arid region resulting in limited plant food availability for Taihangshan macaques, with seasonal variation. Herein, we used a chloroplast trnL DNA metabarcoding approach to identify the plant diet diversity and composition from 100 fecal samples of Taihangshan macaque in four seasons (spring, summer, autumn, and winter) from 2020 to 2021. The results revealed that (1) a total of 48 distinct families, 88 genera, and 52 species within the 105 food items that were consumed by Taihangshan macaques throughout the year; (2) the diversity of food items exhibited significant differences across the four seasons; (3) Rosaceae, Rhamnaceae, Fagaceae, and Poaceae are the preferential food items for Taihangshan macaques and have different relative abundances, fluctuating with seasonal variation. DNA metabarcoding can expand our understanding of the repertoire of food items consumed by Taihangshan macaques by detecting some consumed food items in this population that were not yet discovered using traditional methods. Therefore, the integrative results from traditional methods and DNA metabarcoding can provide a fundamental understanding of dietary composition to guide the conservation management of Taihangshan macaques.

Impacts of Climate Changes on Geographic Distribution of Primula filchnerae, an Endangered Herb in China

Primula filchnerae, an endangered plant endemic to China, has drawn people's attention in recent years due to its ornamental value in flower. It was rarely recorded since being described in 1902, but it was rediscovered in 2009 and is now known from a limited number of sites located in Hubei and Shaanxi Provinces. Since the species is still poorly known, a number of unanswered questions arise related to it: How has P. filchnerae responded to past climate change and how might it respond in the future? Why was P. filchmerae so rarely collected during the past century? We assembled geographic coordinates for P. filchnerae through the field surveys and website searches, and then used a maximum entropy model (MaxEnt) to simulate its potential suitable distribution in six periods with varied carbon emission levels by combining bioclimatic and environmental factors. MaxEnt showed that Min Temperature of the Coldest Month (bio6) and Precipitation of the Coldest Quarter (bio19) affected P. filchnerae's distribution most, with an aggregate contribution >60% and suitable ranges above -5 °C and below 40 mm, respectively. We also analyzed potential habitat distribution in various periods with differing impacts of climate change compared to today's suitable habitats, and in most cases, Shaanxi and Sichuan remained the most stable areas and with possible expansion to the north under various carbon emission scenarios, but the 2050s SSP5-8.5 scenario may be an exception. Moreover, we used MaxEnt to evaluate population shifts, with various scenarios indicating that geometric center would be concentrated in Sichuan Province in China. Finally, conservation strategies are suggested, including the creation of protected areas, long-term monitoring, raising public awareness of plant conservation, situ conservation measures, assisted migration, and species introduction. This study demonstrates how P. filchnerae may have adapted to changes in different periods and provides a scientific basis for germplasm conservation and management.