Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay be...Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood.Here,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China.Specifically,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients.We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems.These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization.The land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna.These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem.We also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna.Taken together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna.These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change.展开更多
Chitwan-Annapuma Landscape(CHAL)in central Nepal is known for its rich biodiversity and the landscape is expected to provide corridors for species range shift in response to climate change.Environmental assessments ha...Chitwan-Annapuma Landscape(CHAL)in central Nepal is known for its rich biodiversity and the landscape is expected to provide corridors for species range shift in response to climate change.Environmental assessments have identified biological invasions and other anthropogenic activities as major threats to the biodiversity in the CHAL.One of the rapidly spreading Invasive Alien Plant species(IAPs)in the CHAL is Parthenium hysterophorus L.,a neotropical invasive weed of global significance.This study aimed to investigate the current and future projected suitable habitat of P.hysterophorus in the CHAL using MaxEnt modelling in three'Representative Concentration Pathways'(RCPs 2.6,4.5 and 8.5)corresponding to different greenhouse gases emissiontrajectories for the year 2050 and 2070.A total of 288species occurrence points,six bioclimatic variablesmean diurnal range,isothermality,annual precipitation,precipitation of driest month,precipitation seasonality,precipitation of driest quarter and two topographic variables(aspect and slope)were selected for MaxEnt modelling.Potential range shift in terms of increase or decline in the suitable habitat areas under the projected scenarios were calculated.Slope and annual precipitation were the most important variables that explained the current distribution of P.hysterophorus.Twenty percent of the total area of CHAL was predicted to be suitable habitat for the growth of P.hysterophorus in the current climatic condition.Highest gain in the suitable habitat of this noxious weed was found under RCP 4.5 scenario in 2050 and 2070.whereas there will be a loss in thesuitable habitat under RCP 8.5 scenario in 2050 and2070.Out of four physiographic regions present in CHAL,three regions-Siwalik,Middle Mountain and High Mountain have suitable habitat for P.hysterophorus under current climatic condition.The mountainous region is likely to be affected more than the Siwalik region by further spread of P.fhysteropfhorus in the future under low(RCP 2.6)to medium(RCP 4.5)emission scenarios.The 展开更多
Two major human-caused threats to ecosystems are habitat modification and the increasing frequency and intensity of extreme weather events.To study the combined effect of these threats,the authors used acoustic monito...Two major human-caused threats to ecosystems are habitat modification and the increasing frequency and intensity of extreme weather events.To study the combined effect of these threats,the authors used acoustic monitoring of bats along a habitat modification gradient on the island of Okinawa,Japan.During the observation period,the island experienced numerous typhoons and one supertyphoon.Native bat species remained active even at high wind speeds(up to 30 m/s in some cases).Milder typhoons had no observable effect on bat populations,with activity levels fully recovering within a few hours or days.The super typhoon also did not seem to affect bats in fully or partially forested habitats but caused their local disappearance at the urban site,which they have not re-colonized three years after the event.Notably,bats that disappeared at the urban site were species roosting in well-protected places such as caves and concrete structures.In all cases,the biomass of small flying insects and the acoustic activity of insects recovered within days after extreme weather events.Thus,the striking difference between habitats in supertyphoon effects on bats cannot be explained by the super typhoon directly killing bats,destroying their roosting sites,or decreasing the abundance of their prey.The results underscore the importance of preserving natural habitats in areas particularly affected by changing climate and show that the survival of species and ecosystems during the numerous episodes of climate change in the Earth’s history does not necessarily mean their ability to survive the accelerating climate change of our time.展开更多
The Human Genome Project(HGP)is a historical and landmark scientific project.In spite of initial controversy it has become a bedrock foundation for much progress in biological science and human health.After the Human ...The Human Genome Project(HGP)is a historical and landmark scientific project.In spite of initial controversy it has become a bedrock foundation for much progress in biological science and human health.After the Human Genome Project was completed in the early 2000s,next generation sequencing technologies were developed and that has revolutionized genomics.Here is a brief account of the May 1985 meeting at University of California Santa Cruz.Historical accounts often begin with a the Department of Energy(DOE)meeting in Santa Fe in March 1986 and neglect including the Santa Cruz meeting[1],although sometimes it is discussed[2].展开更多
In vertebrate limb, a group of specialized epithelial cells called Apical Ectodermal Ridge (AER) form at the boundary of dorsal and ventral limb ectoderm. Recent experiments suggest that AER forms at the boundary of F...In vertebrate limb, a group of specialized epithelial cells called Apical Ectodermal Ridge (AER) form at the boundary of dorsal and ventral limb ectoderm. Recent experiments suggest that AER forms at the boundary of Fringe expressing and Fringe non-expressing cells by a specific type of receptor-ligand interaction called as inductive signaling, involving the transmembrane proteins Notch, Serrate and Delta. Experiments conducted on Drosophila wing disc have shown that Fringe inhibits the binding ability of Serrate ligand to Notch and enhances that of Delta to Notch. Although several of the signaling elements have been identified experimentally, it remains unclear how the inter-cellular interactions can give rise to such a boundary of specialized cells. Here we present an ordinary differential equation (ODE) model involving Delta→Notch and Serrate→Notch interactions between juxtaposed Fringe expressing and Fringe nonexpressing cells. When simulated in a compartmentalized set up, this model gives rise to high Notch levels at the boundary of Fringe expressing and Fringe non-expressing cells.展开更多
基金This research was funded by the Biodiversity Conservation Program of the Ministry of Ecology and Environment,China,Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)CAS 135 program(2017XTBG-F01)EPE was supported by subsidy funding to OIST and Japan Society for the Promotion of Science KAKENHI(17K15180).
文摘Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood.Here,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China.Specifically,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients.We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems.These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization.The land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna.These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem.We also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna.Taken together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna.These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change.
基金support provided by the Feed the Future Innovation Lab for Integrated Pest Management of the U.S. Agency for International Development, under the terms of Cooperative Agreement No. AID–OAA-L-15-00001supported by International Foundation for Science (Sweden), Nepal Academy of Science and Technology (Nepal), and National Trust for Nature Conservation (Nepal)
文摘Chitwan-Annapuma Landscape(CHAL)in central Nepal is known for its rich biodiversity and the landscape is expected to provide corridors for species range shift in response to climate change.Environmental assessments have identified biological invasions and other anthropogenic activities as major threats to the biodiversity in the CHAL.One of the rapidly spreading Invasive Alien Plant species(IAPs)in the CHAL is Parthenium hysterophorus L.,a neotropical invasive weed of global significance.This study aimed to investigate the current and future projected suitable habitat of P.hysterophorus in the CHAL using MaxEnt modelling in three'Representative Concentration Pathways'(RCPs 2.6,4.5 and 8.5)corresponding to different greenhouse gases emissiontrajectories for the year 2050 and 2070.A total of 288species occurrence points,six bioclimatic variablesmean diurnal range,isothermality,annual precipitation,precipitation of driest month,precipitation seasonality,precipitation of driest quarter and two topographic variables(aspect and slope)were selected for MaxEnt modelling.Potential range shift in terms of increase or decline in the suitable habitat areas under the projected scenarios were calculated.Slope and annual precipitation were the most important variables that explained the current distribution of P.hysterophorus.Twenty percent of the total area of CHAL was predicted to be suitable habitat for the growth of P.hysterophorus in the current climatic condition.Highest gain in the suitable habitat of this noxious weed was found under RCP 4.5 scenario in 2050 and 2070.whereas there will be a loss in thesuitable habitat under RCP 8.5 scenario in 2050 and2070.Out of four physiographic regions present in CHAL,three regions-Siwalik,Middle Mountain and High Mountain have suitable habitat for P.hysterophorus under current climatic condition.The mountainous region is likely to be affected more than the Siwalik region by further spread of P.fhysteropfhorus in the future under low(RCP 2.6)to medium(RCP 4.5)emission scenarios.The
文摘Two major human-caused threats to ecosystems are habitat modification and the increasing frequency and intensity of extreme weather events.To study the combined effect of these threats,the authors used acoustic monitoring of bats along a habitat modification gradient on the island of Okinawa,Japan.During the observation period,the island experienced numerous typhoons and one supertyphoon.Native bat species remained active even at high wind speeds(up to 30 m/s in some cases).Milder typhoons had no observable effect on bat populations,with activity levels fully recovering within a few hours or days.The super typhoon also did not seem to affect bats in fully or partially forested habitats but caused their local disappearance at the urban site,which they have not re-colonized three years after the event.Notably,bats that disappeared at the urban site were species roosting in well-protected places such as caves and concrete structures.In all cases,the biomass of small flying insects and the acoustic activity of insects recovered within days after extreme weather events.Thus,the striking difference between habitats in supertyphoon effects on bats cannot be explained by the super typhoon directly killing bats,destroying their roosting sites,or decreasing the abundance of their prey.The results underscore the importance of preserving natural habitats in areas particularly affected by changing climate and show that the survival of species and ecosystems during the numerous episodes of climate change in the Earth’s history does not necessarily mean their ability to survive the accelerating climate change of our time.
文摘The Human Genome Project(HGP)is a historical and landmark scientific project.In spite of initial controversy it has become a bedrock foundation for much progress in biological science and human health.After the Human Genome Project was completed in the early 2000s,next generation sequencing technologies were developed and that has revolutionized genomics.Here is a brief account of the May 1985 meeting at University of California Santa Cruz.Historical accounts often begin with a the Department of Energy(DOE)meeting in Santa Fe in March 1986 and neglect including the Santa Cruz meeting[1],although sometimes it is discussed[2].
文摘In vertebrate limb, a group of specialized epithelial cells called Apical Ectodermal Ridge (AER) form at the boundary of dorsal and ventral limb ectoderm. Recent experiments suggest that AER forms at the boundary of Fringe expressing and Fringe non-expressing cells by a specific type of receptor-ligand interaction called as inductive signaling, involving the transmembrane proteins Notch, Serrate and Delta. Experiments conducted on Drosophila wing disc have shown that Fringe inhibits the binding ability of Serrate ligand to Notch and enhances that of Delta to Notch. Although several of the signaling elements have been identified experimentally, it remains unclear how the inter-cellular interactions can give rise to such a boundary of specialized cells. Here we present an ordinary differential equation (ODE) model involving Delta→Notch and Serrate→Notch interactions between juxtaposed Fringe expressing and Fringe nonexpressing cells. When simulated in a compartmentalized set up, this model gives rise to high Notch levels at the boundary of Fringe expressing and Fringe non-expressing cells.
