Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation,thus enabling range expansion.In contrast,narrow-range species are confined ...Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation,thus enabling range expansion.In contrast,narrow-range species are confined to restricted geographical areas and are ecologically adapted to narrow environmental conditions,thus limiting their ability to expand into novel environments.However,the genomic mechanisms underlying the differentiation between closely related species with varying distribution ranges remain poorly understood.The Niviventer niviventer species complex(NNSC),consisting of highly abundant wild rats in Southeast Asia and China,offers an excellent opportunity to investigate these questions due to the presence of both widespread and narrow-range species that are phylogenetically closely related.In the present study,we combined ecological niche modeling with phylogenetic analysis,which suggested that sister species cannot be both widespread and dominant within the same geographical region.Moreover,by assessing heterozygosity,linkage disequilibrium decay,and Tajima's D analysis,we found that widespread species exhibited higher genetic diversity than narrow-range species.In addition,by exploring the“genomic islands of speciation”,we identified 13 genes in highly divergent regions that were shared by the two widespread species,distinguishing them from their narrow-range counterparts.Functional annotation analysis indicated that these genes are involved in nervous system development and regulation.The adaptive evolution of these genes likely played an important role in the speciation of these widespread species.展开更多
DEAR EDITOR,Mountainous regions are generally characterized by high species turnover,yet studies applying novel conceptual frameworks to analyze the spatial structure and organization of montane biota along elevationa...DEAR EDITOR,Mountainous regions are generally characterized by high species turnover,yet studies applying novel conceptual frameworks to analyze the spatial structure and organization of montane biota along elevational gradients remain scarce.Based on the zeta diversity framework—a novel turnover metric that focuses on average number of species shared across sites—and a comprehensive presence-absence dataset of small mammals collected from 22 elevational gradients in the Mountains of Southwest China(MSC).展开更多
Mineral licks are important components of terrestrial ecosystems that have special value to the maintenance of fluid balance of mammals,by providing them with essential mineral nutrients such as sodium,calcium,and mag...Mineral licks are important components of terrestrial ecosystems that have special value to the maintenance of fluid balance of mammals,by providing them with essential mineral nutrients such as sodium,calcium,and magnesium.In the Anzihe Nature Reserve,southwest China,seven species of ungulates and one species of primates were frequently observed visiting the mineral licks in high densities.As a consequence,mineral licks have attracted illegal hunters and facilitated the spread of parasites and diseases,leading to a depletion of local populations.Therefore,we suggest that regions with abundant mineral licks should be designated as key protected areas in the Anzihe Nature Reserve and relevant zones for animal health surveillance.展开更多
基金supported by the Guangdong Provincial Key R&D Program (2022B1111040001)the Second Tibetan Plateau Scientific Expedition and Research Program (2019QZKK0402/2019QZKK0501)National Natural Science Foundation of China (32170426)。
文摘Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation,thus enabling range expansion.In contrast,narrow-range species are confined to restricted geographical areas and are ecologically adapted to narrow environmental conditions,thus limiting their ability to expand into novel environments.However,the genomic mechanisms underlying the differentiation between closely related species with varying distribution ranges remain poorly understood.The Niviventer niviventer species complex(NNSC),consisting of highly abundant wild rats in Southeast Asia and China,offers an excellent opportunity to investigate these questions due to the presence of both widespread and narrow-range species that are phylogenetically closely related.In the present study,we combined ecological niche modeling with phylogenetic analysis,which suggested that sister species cannot be both widespread and dominant within the same geographical region.Moreover,by assessing heterozygosity,linkage disequilibrium decay,and Tajima's D analysis,we found that widespread species exhibited higher genetic diversity than narrow-range species.In addition,by exploring the“genomic islands of speciation”,we identified 13 genes in highly divergent regions that were shared by the two widespread species,distinguishing them from their narrow-range counterparts.Functional annotation analysis indicated that these genes are involved in nervous system development and regulation.The adaptive evolution of these genes likely played an important role in the speciation of these widespread species.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program (STEP,2019QZKK0501,2019QZKK0402)National Natural Science Foundation of China (32271736)Survey of Wildlife Resources in Key Areas of Xizang (ZL202203601)。
文摘DEAR EDITOR,Mountainous regions are generally characterized by high species turnover,yet studies applying novel conceptual frameworks to analyze the spatial structure and organization of montane biota along elevational gradients remain scarce.Based on the zeta diversity framework—a novel turnover metric that focuses on average number of species shared across sites—and a comprehensive presence-absence dataset of small mammals collected from 22 elevational gradients in the Mountains of Southwest China(MSC).
基金This work was supported by the National Science and Technology Basic Resources Survey Program of China[2019FY100204]Institute of Tibetan Plateau Research,Chinese Academy of Sciences[2019QZKK0402,2019QZKK0501]。
文摘Mineral licks are important components of terrestrial ecosystems that have special value to the maintenance of fluid balance of mammals,by providing them with essential mineral nutrients such as sodium,calcium,and magnesium.In the Anzihe Nature Reserve,southwest China,seven species of ungulates and one species of primates were frequently observed visiting the mineral licks in high densities.As a consequence,mineral licks have attracted illegal hunters and facilitated the spread of parasites and diseases,leading to a depletion of local populations.Therefore,we suggest that regions with abundant mineral licks should be designated as key protected areas in the Anzihe Nature Reserve and relevant zones for animal health surveillance.