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Aim: Similar environmental selection pressures drive the occurrence of convergent evolution among species. However, studies on this phenomenon are scarce at the population level. Here, we used two waist‐shaped bugs to test the hypothesis that similar high‐elevation habitat environments could lead to similar genetic adaptations among populations of different species. Location: East Asia. Taxa: Malcus sinicus Štys, 1967 & Malcus insularis Štys, 1967. Methods: Population genetic structure was determined by phylogenetic and phylogeographical analyses. Demographic history was inferred by comparing simulated history models. Suitable habitat from the last interglacial period (LIG) to the present was predicted by ecological niche modelling (ENM). Convergent evolutionary processes were jointly assessed by the comparison of population ecological differences and the principal component analysis of environmentally related single‐nucleotide polymorphisms (SNPs). Results: Our results showed that the land bridge in the Pleistocene helped ancestral populations of M. sinicus and M. insularis diffuse from mainland China to Taiwan Island. Subsequently, the geographical barrier imposed by the Taiwan Strait promoted the species differentiation. Geographic isolation and adaptive evolution jointly promoted the population differentiation in M. sinicus. Genetic similarity was found between the populations of M. sinicus in southwestern China (sin‐YN) and M. insularis on Taiwan Island (ins‐TW). Temperature‐related environmental factors and elevation were found to similarly and significantly clustered with ins‐TW and sin‐YN and were clearly distinguished from the other low−/mid‐elevation populations of M. sinicus (sin‐EA). Furthermore, the SNPs related to these environmental factors presented the same clustering results. Main Conclusions: Our study revealed a novel disjunct distribution pattern between southwestern China and Taiwan Island at the population level and provided evidence of convergent evolution of local populations in high‐elevation environments. Here, we revealed that similar environmental selection pressures can drive the occurrence of convergent evolution at the population level among different species. [ABSTRACT FROM AUTHOR]

Simple Summary: The stalk-eyed seed bug Chauliops fallax is an important agricultural pest of soybean and was first reported to occur outside East Asia. Here, the native evolutionary history, recent invasion history, and potential invasion threats of C. fallax were reported for the first time based on population genetic methods and ecological niche modelling. Four native genetic groups (EA, WE, TL, and XZ) and an east–west differentiation pattern consistent with the geographical characteristics of three-step landforms were well supported in China. The Kashmir sample was found to come from a recent invasion event, and the invasive source was determined to be the populations of the coastal areas of southern China. North America might have high a risk of invasion, which poses a serious threat to local soybean production. Our results provided new insights into the monitoring and management of Chauliops fallax in the early invasion stage. The short stay at the beginning of the invasion process is a critical time for invasive species identification and preventing invasive species from developing a wider distribution and significant economic impact. The stalk-eyed seed bug Chauliops fallax is an important agricultural pest of soybean and was first reported to occur outside East Asia. Here, we reported the native evolutionary history, recent invasion history, and potential invasion threats of C. fallax for the first time based on population genetic methods and ecological niche modelling. The results showed that four native East Asian genetic groups (EA, WE, TL, and XZ) were well supported, showing an east-west differentiation pattern consistent with the geographical characteristics of three-step landforms in China. Two main haplotypes existed: Hap1 might have experienced a rapid northwards expansion process after the LGM period, and Hap5 reflected local adaptation to the environment in southeastern China. The Kashmir sample was found to come from the recent invasion of populations in the coastal areas of southern China. Ecological niche modelling results suggested that North America has a high risk of invasion, which might pose a serious threat to local soybean production. In addition, with future global warming, the suitable habitat in Asia will move towards the higher latitude region and gradually deviate from the soybean planting area, which indicates the threat of C. fallax to soybean production in Asia will decrease in the future. The results could provide new insights into the monitoring and management of this agricultural pest in the early invasion stage. [ABSTRACT FROM AUTHOR]

The latest Coupled Model Intercomparison Project Phase 6 (CMIP6) proposes new shared pathways (SSPs) that incorporate socioeconomic development with more comprehensive and scientific experimental designs; however, few studies have been performed on the projection of future multibasin hydrological changes in China based on CMIP6 models. In this paper, we use the Equidistant Cumulative Distribution Function method (EDCDFm) to perform downscaling and bias correction in daily precipitation, daily maximum temperature, and daily minimum temperature for six CMIP6 models based on the historical gridded data from the high-resolution China Meteorological Forcing Dataset (CMFD). We use the bias-corrected precipitation, temperature, and daily mean wind speed to drive the variable infiltration capacity (VIC) hydrological model, and study the changes in multiyear average annual precipitation, annual evapotranspiration and total annual runoff depth relative to the historical baseline period (1985–2014) for the Chinese mainland, basins and grid scales in the 21st century future under the SSP2-4.5 and SSP5-8.5 scenarios. The study shows that the VIC model accurately simulates runoff in major Chinese basins; the model data accuracy improves substantially after downscaling bias correction; and the future multimodel-mean multiyear average annual precipitation, annual evapotranspiration, and total annual runoff depth for the Chinese mainland and each basin increase relative to the historical period in near future (2020–2049) and far future (2070–2099) under the SSP2-4.5 and SSP5-8.5 scenarios. The new CMIP6-based results of this paper can provide a strong reference for extreme event prevention, water resource utilization and management in China in the 21st century. [ABSTRACT FROM AUTHOR]

Since the beginning of the Holocene era, human activities have seriously impacted animal habitats and vegetative environments. Species that are dependent on natural habitats or with narrow niches might be more severely affected by habitat changes. Malcus inconspicuus is distributed in subtropical China and highly dependent on the mountain environment. Our study investigated the role of the mountainous landscape in the historical evolution of M. inconspicuus and the impact of Holocene human activities on it. A phylogeographical approach was implemented with integrative datasets including double‐digest restriction site‐associated DNA (ddRAD), mitochondrial data, and distribution data. Three obvious clades and an east–west phylogeographical pattern were found in subtropical China. Mountainous landscape has "multifaceted" effects on the evolutionary history of M. inconspicuus, it has contributed to population differentiation, provided glacial refuges, and provided population expansion corridors during the postglacial period. The effective population size (Ne) of M. inconspicuus showed a sharp decline during the Holocene era, which revealed a significantly negative correlation with the development of cropland in a hilly area at the same time and space. It supported that the species which are highly dependent on natural habitats might undergo greater impact when the habitat was damaged by agricultural activities and we should pay more attention to them, especially in the land development of their distribution areas. [ABSTRACT FROM AUTHOR]

1. Vicariance and ecological adaptation are two evolutionary mechanisms that can generate biodiversity. Evidence from recent studies has shown that the patterns of genetic variation of species distributed in South China are influenced by the Taiwan Strait and/or the Qinghai‐Tibet Plateau (QTP). 2. This study sequenced three mitochondrial and one nuclear genes from 174 individuals Carbula crassiventris and conducted phylogenetic and phylogeographical analyses, asymmetric gene flow estimation, intraspecific divergence time and historical demographic reconstruction, morphological comparison, ecological niche modelling (ENM), and isolation‐by‐distance (IBD) and isolation‐by‐environment (IBE) modelling to test if vicariance and ecological adaptation jointly affected biogeographic patterns in South China. 3. According to the results of phylogenetic and phylogeographical analyses, C. crassiventris was divided into three populations (Mainland, Xizang, and Taiwan). Asymmetric gene flows were detected from the Mainland to Xizang populations and from the Mainland to Taiwan populations. Morphological comparison showed that the individuals from the three defined populations have significant differences in four variables. The ENM results suggested that suitable habitat has expanded from the Last Glacial Maximum to the present. Partial Mantel tests indicated that individuals in the Mainland population were not dispersal‐limited, regardless of geographic or environmental distance, but that a significant IBE relationship was present in the Mainland–Xizang lineage. When including the Taiwan population in the dataset, significant IBD and IBE relationships were detected. 4. This study revealed that both vicariance, with the Taiwan Strait as a geographical barrier, and ecological adaptation, in both the QTP and Taiwan, jointly influence population divergence of C. crassiventris. [ABSTRACT FROM AUTHOR]

• Future DHW intensity rises over 4 times, population exposed increases by over 1.5 times. • The Yangtze and Yellow River basins undergo a significant DHW increase. • Future DHW-exposed population increase 1.61–2.41 times over the historical baseline. • The temperature increase is the main driver of DHW event escalation. Global warming has accelerated the interregional hydrological cycle, resulting in a significant increase in the frequency and intensity of extreme events worldwide. These events often involve a combination of spatial and temporal factors, giving rise to compound events. Among them are rapid transitions from dry and hot conditions to wet (DHW) events, which can have more severe impacts on human societies and ecosystems than individual extreme events. Urbanization not only heightens the likelihood of disasters but also exacerbates the exposure of affected populations. However, there has been insufficient attention given to understanding the connections between these successive compound events and the heightened risks posed by the increasing urbanization. In this study, we used bias-corrected daily precipitation and maximum temperature data simulated by the Coupled Model Intercomparison Project Phase 6 (CMIP6) model, along with historical and future daily runoff data simulated by the Variable Infiltration Capacity (VIC) model. We systematically investigated the spatiotemporal changes (i.e., frequency, duration, intensity, and compound probability) in DHW events in China during the upper historical period (1979–2014) and under two medium and high emission scenarios (2015–2100) − Shared Socioeconomic Pathways (SSP245 and SSP585). Furthermore, we examined how extreme runoff responds to variations in maximum temperature and daily precipitation during DHW events. We also evaluated the potential population and urban exposure to DHW events using dynamic future population and urban expansion data to assess the potential risks. Our results indicate that the multi-model ensemble predicts varying spatial patterns of future DHW events under SSP245 and SSP585 scenarios. The frequency and duration of these events are expected to decrease by approximately 20–25% in the Northwest region under both scenarios. At the same time, the middle and lower plains of the Yangtze and Yellow River Basins experience increased occurrence, broader geographical impact, and higher DHW event intensity alongside urban expansion and population growth in these regions. Specifically, event intensity is anticipated to increase by a factor of approximately 7–11. Temporally, we expect short-duration, high-intensity DHW events to occur in the Yangtze and Yellow River basins around 2023, 2038, and 2058, respectively. The primary driver for the future rise in population exposure to DHW events is the expected increase in event frequency in the middle and lower plains of the Yangtze and Yellow River basins, concurrent with population growth in these regions. Under the medium emission scenario, the total exposed population to DHW events in China is predicted to be 1.61 times higher than the historical baseline. In contrast, the high-emission scenario estimates a total population of 2.41 times higher than the historical baseline period. Most of the DHW events occurred in regions that exhibit a positive dependence between high temperature and high runoff events, serving as the primary driver of DHW events. Urbanization has a positive impact on DHW events, with the effect under high emissions being approximately 30% higher than during the historical base period. Additionally, it is indicated that future DHW events will exhibit higher sensitivity to global warming, with intensity projected to increase approximately fourfold and the exposed population to rise by about 1.5 times for every 1 °C of global warming. This research enhances our understanding of forecasting future compound hydrometeorological extreme events under different scenarios and provides insight into the role of climate change and urbanization in shaping these events in China. [ABSTRACT FROM AUTHOR]