Although hunting in the north-eastern Atlantic forest of Brazil began more than 500 years ago, no study to date has evaluated its impacts on the region’s mammalian fauna. For one year we carried out diurnal and noctu...Although hunting in the north-eastern Atlantic forest of Brazil began more than 500 years ago, no study to date has evaluated its impacts on the region’s mammalian fauna. For one year we carried out diurnal and nocturnal surveys using the Line Transect method in seven forest fragments varying from 7.32 ha to 469.76 ha, within a 4000 ha forest island archipelago, in Pernambuco State, Atlantic forest of northeastern Brazil. We calculated species density, population size, biomass and synergetic biomass, and recorded direct and indirect human impacts along the study transects. We recorded 44 mammalian species, of which 45.5% (n = 20) went extinct through hunting. The smallest forest fragment had the lowest richness, diversity, population size, and total biomass. It also had no synergetic biomass. The largest fragment had the highest richness, total density, and population size. There was a statistically significant relationship between fragment area and number of gunshots heard and suspended hunting platforms found;between population size and gunshots heard, suspended hunting platforms, free-roaming and feral dogs, and between total density and free-roaming and feral dogs. After more than 500 years of colonization hunting is still devastating, with larger fragments being linked to more hunters. Higher mammal abundances attracted more free-roaming and feral dogs, which have adapted to hunt wildlife on their own. Unless we protect every single forest fragment and create sustainable landscapes, we will not be able to save this hotspot’s hotspot.展开更多
Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis...Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis, we evaluated the influence of small mammal prey—present in 95% of pellets—on the reproductive performance of the sakers. In Mongolia, three species comprised 95% of the identified small mammals: Mongolian Gerbil (Meriones unguiculatus, 39%), Brandt's Vole (Lasiopodomys brandtii, 49%) and Daurian Pika (Ochotona dauurica, 7%). We found a strong positive association between the proportion of small mammals in the diet and key breeding parameters of sakers. Clutch size, fledged brood sizes, and nest success all increased with a mammal-rich diet. Earlier laying was also linked to higher small mammal intake and was independently associated with improved breeding outcomes. These findings highlight a critical role of small mammal prey in shaping the reproductive success of sakers. Conserving and restoring grassland habitats that support abundant prey populations is essential for sustaining saker populations and achieving long-term conservation goals.展开更多
Mammal distribution is shaped by different ecological and anthropogenic factors,and the pattern varies depending on their sensitivity thresholds,food and habitat preferences,ecological roles,and physical traits.The pr...Mammal distribution is shaped by different ecological and anthropogenic factors,and the pattern varies depending on their sensitivity thresholds,food and habitat preferences,ecological roles,and physical traits.The present study investigated the influence of ecological and anthropogenic factors on the distribution of mammal species communities across different trophic levels and body sizes in Myanmar's Htamanthi Wildlife Sanctuary(HWS).The values of mammal characteristics,ecological,and anthropogenic factors were analyzed in ArcMap software.Most of the large and small sized mammals,whose distribution decreases with elevation,were observed near the main streams.Across mammal tropic levels,the omnivores and herbivores were mostly observed farther from gold mining sites.In terms of forage plant effect on mammal community,floral forage plants and the presence of climber negatively affected mammal species across different trophic levels.Moreover,presence of resin trees also has a substantial impact on the distribution of medium-large animals and omnivorous mammals as trophic niche factors.Overall,our findings highlight the crucial role that ecological and anthropogenic factors play in shaping mammal distribution in the HWS.This underscores the importance of simultaneously conserving both habitat and mammal diversity in HWS,especially in the face of a changing climate and environment.展开更多
Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the ...Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that： 1 ） although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution （ 15 species were dispersed over three zones and two species over two zones） , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2） whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3）the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4） in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas.展开更多
An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were c...An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders （Rodentia, Insectivora, Scandentia and Carnivora）, while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts.展开更多
In recent years,explosion of research in the early Tertiary mammals of India has attracted widespread interest because of the importance of this fauna in understanding biogeographic origins,early evolution,and dispers...In recent years,explosion of research in the early Tertiary mammals of India has attracted widespread interest because of the importance of this fauna in understanding biogeographic origins,early evolution,and dispersal patterns of several modern mammal orders as well for its paleogeographic implications.Although Paleocene mammals are yet to be discovered in the Indian subcontinent,Indian Early Eocene mammal faunas are now becoming increasingly important in debates concerning the origins of several modern terrestrial orders.展开更多
Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could ex...Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could exert hypoxic stresses such as oxidative damage on organisms living in these environments.In order to cope with these stresses,organisms have evolved specific strategies to adapt to hypoxia,including changes in physiology,gene expression regulation,and genetic mutations.Here,we review how mammals have adapted to the three high-altitude plateaus of the world,the limited oxygen dissolved in deep water habitats,and underground tunnels,with the aim of better understanding the adaptation of mammals to hypoxia.展开更多
Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement （REM） sleep state. During REM sleep, postu...Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement （REM） sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to sur- face at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately -90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin＇s theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.展开更多
High-altitude and marine mammals inhabit distinct ecosystems but share a common challenge:hypoxia.To survive in low-oxygen environments,these species have evolved similar phenotypic pulmonary adaptations,characterized...High-altitude and marine mammals inhabit distinct ecosystems but share a common challenge:hypoxia.To survive in low-oxygen environments,these species have evolved similar phenotypic pulmonary adaptations,characterized by a high density of elastic fibers.In this study,we explored the molecular mechanisms underlying these adaptations,focusing on pulmonary fibrosis and hypoxia tolerance through comparative genomics and convergent evolution analyses.We observed significant expansions and contractions in certain gene families across both high-altitude and marine mammals,closely associated with processes involved in pulmonary fibrosis.Notably,members of the keratin gene family,such as KRT17 and KRT14,appear to be associated with the development of the dense elastic fiber phenotype observed in the lungs of hypoxia-tolerant mammals.Through selection pressure and amino acid substitution analyses,we identified multiple genes exhibiting convergent accelerated evolution,positive selection,and amino acid substitution in these species,associated with adaptation to hypoxic environments.Specifically,the convergent evolution of ZFP36L1,FN1,and NEDD9 was found to contribute to the high density of elastic fibers in the lungs of both high-altitude and marine mammals,facilitating their hypoxia tolerance.Additionally,we identified convergent amino acid substitutions and gene loss events associated with sperm development,differentiation,and spermatogenesis,such as amino acid substitutions in SLC26A3 and pseudogenization of CFAP47,as confirmed by PCR.These genetic alterations may be linked to changes in the reproductive capabilities of these animals.Overall,this study offers novel perspectives on the genetic and molecular adaptations of high-altitude and marine mammals to hypoxic environments,with a particular emphasis on pulmonary fibrosis.展开更多
Mammalian surveys are vital tools for effective managements and conservation strategies. A survey was conducted to investigate the species composition, relative abundance and to determine their major threats in Weyngu...Mammalian surveys are vital tools for effective managements and conservation strategies. A survey was conducted to investigate the species composition, relative abundance and to determine their major threats in Weyngus Forest, West Gojjam Zone, Amhara Region, Ethiopia. The data were collected from April 2020 to June 2020. Transect method and subjective interviews were used to collect data for the study. A total of 11 species of medium and large sized mammals belonging to six orders and eight families were recorded by direct and indirect evidences. Porcupine (Hystrix cristata), Vervet monkey (Chlorocebus aethiops), and Coloubus monkey (Colobus guereza) were among the medium-sized mammals while, Spotted hyena (Crocuta crocuta), Bushbuck (Tragelaphus scriptus) and Common duiker (Sylvicapra grimmia) were among the large-sized mammals recorded in the study area. Vervet monkey has been the most frequently observed species, whereas spotted hyena was observed less often. Simpson’s Similarity Index (SI) showed a significant overlap of mammalian species composition between scrubland and natural forest (SI = 0.62). Illegal logging of trees for fuel wood, agricultural land expansion, illegal hunting and land degradation were the main threats of mammals in the study area. Community participation and awareness creation are highly recommended to limit the impact of anthropogenic activities threatening wildlife.展开更多
Since the last comprehensive review of the then stateof-the-art progress in paleomammalogy in 2010,there has been substantial further advances in understanding the middle ear development and phylogeny of Mesozoic mamm...Since the last comprehensive review of the then stateof-the-art progress in paleomammalogy in 2010,there has been substantial further advances in understanding the middle ear development and phylogeny of Mesozoic mammals,evolution of early primates,and so on.The post-dentary bone morphologies of two Jurassic mammaliaforms,Dianoconodon youngi and Feredocodon chowi,demonstrate the detachment mechanism of post-dentary bones from the dentary and the eventual breakdown of the Meckel’s cartilage during the evolution of mammaliaforms.The middle ear of the Early Cretaceous Liaoconodon hui defines the transitional mammalian middle ear.The Creataceous stem therian Origolestes lii displays the decoupling of hearing and chewing apparatuses and functions.In addition,the discovery of Ambolestes zhoui,an Early Cretaceous eutherian,demonstrates that Sinodelphys,the oldest purported marsupial,is actually a eutherian.The early Eocene haplorrhine primate,Archicebus achilles,resurrects the possibility that Asia was an important stage for early primate evolution.Not only has knowledge concerning these topics been further deepened,but new knowledge has also been acquired concerning Late Cenozoic herbivores and primates in paleomammalogy on the basis of these new discoveries.展开更多
Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete sp...Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preservedhairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao,western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and lifehabits of Mesozoic symmetrodont mammals.展开更多
The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted ...The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted on Afromontane ecosystems have compared the altitudinal patterns of small mammal diversity. We investigated the species diversity and abundance of non-volant small mammals(hereafter ‘small mammals')on Mt. Kenya, the second tallest mountain in Africa,using a standard sampling scheme. Nine sampling transects were established at intervals of 200 m on the eastern(Chogoria) and western(Sirimon) slopes.A total of 1 905 individuals representing 25 species of small mammals were trapped after 12 240 trap-nights.Abundance was highest at mid-elevations on both slopes.However, species richness and their distribution patterns differed between the two slopes. More species were recorded on Chogoria(24) than on Sirimon(17). On Chogoria, species richness was higher at mid-high elevations, with a peak at mid-elevation(2 800 m a.s.l.),whereas species richness showed little variation on the Sirimon slope. These results indicate that patterns of species diversity can differ between slopes on the same mountain. In addition, we extensively reviewed literature on Mt. Kenya's mammals and compiled a comprehensive checklist of 76 mammalian species. However, additional research is required to improve our understanding of smal mammal diversity in mountain habitats in Africa.展开更多
In mammals, spinal cord injury (SCI) is a devastating event that can lead to a permanent loss of motor, sensory and autonomic functions below the site of injury. In the last years, the role of different neurotransmitt...In mammals, spinal cord injury (SCI) is a devastating event that can lead to a permanent loss of motor, sensory and autonomic functions below the site of injury. In the last years, the role of different neurotransmitter systems on regeneration and recovery from SCI has been deciphered. For example, studies in lampreys have shown that neurotransmitters play a key role in modulating the survival and regeneration of brainstem descending neurons after SCI (Romaus-Sanjurjo et al., 2018;Sobrido-Camean et al., 2018).展开更多
In this article,authors review the current knowledge of Bartonella infection in small mammals including rodents,insectivores,bats and exotic small mammal pets and their vectors in Asia.Species of Bartonella are Gram-n...In this article,authors review the current knowledge of Bartonella infection in small mammals including rodents,insectivores,bats and exotic small mammal pets and their vectors in Asia.Species of Bartonella are Gram-negative intracellular bacteria that infect erythrocytes of various mammalian and non-mammalian animals and mainly transmitted by blood sucking arthropod vectors.The genus Bartonella includes several species of important human diseases with severe clinical signs.Several new Bartonella species were isolated from rodents and other small mammals,and from human patients in Asia.Bartonella species are identified using standard polymerase chain reaction amplification and a sequencing targeting two housekeeping genes(glt.A and rpoB) and the internal transcribed spacer fragment.Authors also discuss the implications in term of potential emerging zoonotic diseases.展开更多
The current and dominant theory about the origin of modern humans is the out-of-Africa hypothesis, which asserts that populations of Homo sapiens left Africa 100,000 years ago and replaced indigenous populations of hu...The current and dominant theory about the origin of modern humans is the out-of-Africa hypothesis, which asserts that populations of Homo sapiens left Africa 100,000 years ago and replaced indigenous populations of humans in Eurasia. Many scholars equated the out-of-Africa dispersal of humans with paleoenvironmental changes. However, until now, few have paid special attention to the faunal data and whether or not faunal patterns are supportive of the popular theory. Recent comparative study of the Chinese fauna shows that the communication of faunas between Africa and East Asia could have occurred during the Neogene, but it was very limited during the Pleistocene. In the Chinese Quaternary fauna, only 16% of the genera are also present in the sub-Saharan African fauna. There is also no element among the dominant taxa of the Chinese Quaternary fauna which can be related to the African fauna. There is no reliable proof for the existence of Hippopotamus and Giraffa, as well as Panthera leo, during the Quaternary in China. Two controversial taxa are Acinonyx and Crocuta, about which there is still argument concerning their species identification in Eurasia. It is possible that both of the genera have co-specific taxa in Africa and Eurasia. Although the two genera are confined to Africa today, they did have a long evolutionary history in China. For the Out of Africa hypothesis for Homo sapiens, the implications of the limited faunal interchanges between China and Africa are not completely clear yet.展开更多
Many mammals risk damage from oxidative stress stemming from frequent dives(i.e., cycles of ischemia/reperfusion and hypoxia/reoxygenation),high altitude and subterranean environments, or powered flight. Purine metabo...Many mammals risk damage from oxidative stress stemming from frequent dives(i.e., cycles of ischemia/reperfusion and hypoxia/reoxygenation),high altitude and subterranean environments, or powered flight. Purine metabolism is an essential response to oxidative stress, and an imbalance between purine salvage and de novo biosynthesis pathways can generate damaging reactive oxygen species(ROS). Here, we examined the evolution of 117 purine metabolism-related genes to explore the accompanying molecular mechanisms of enhanced purine metabolism in mammals under high oxidative stress. We found that positively selected genes,convergent changes, and nonparallel amino acid substitutions are possibly associated with adaptation to oxidative stress in mammals. In particular, the evolution of convergent genes with c AMP and c GMP regulation roles may protect mammals from oxidative damage. Additionally, 32 genes were identified as under positive selection in cetaceans, including key purine salvage enzymes(i.e., HPRT1), suggesting improved re-utilization of non-recyclable purines avoid hypoxanthine accumulation and reduce oxidative stress. Most intriguingly, we found that six unique substitutions in cetacean xanthine dehydrogenase(XDH), an enzyme that regulates the generation of the ROS precursor xanthine oxidase(XO) during ischemic/hypoxic conditions, show enhanced enzyme activity and thermal stability and diminished XO conversion activity. These functional adaptations are likely beneficial for cetaceans by reducing radical oxygen species production during diving. In summary, our findings offer insights into the molecular and functional evolution of purine metabolism genes in mammalian oxidative stress adaptations.展开更多
Optogenetics is a newly-introduced technology in the life sciences and is gaining increasing attention.It refers to the combination of optical technologies and genetic methods to control the activity of specific cell ...Optogenetics is a newly-introduced technology in the life sciences and is gaining increasing attention.It refers to the combination of optical technologies and genetic methods to control the activity of specific cell groups in living tissue,during which high-resolution spatial and temporal manipulation of cells is achieved.Optogenetics has been applied to numerous regions,including cerebral cortex,hippocampus,ventral tegmental area,nucleus accumbens,striatum,spinal cord,and retina,and has revealed new directions of research in neuroscience and the treatment of related diseases.Since optogenetic tools are controllable at high spatial and temporal resolution,we discuss its applications in these regions in detail and the recent understanding of higher brain functions,such as reward-seeking,learning and memory,and sleep.Further,the possibilities of improved utility of this newly-emerging technology are discussed.We intend to provide a paradigm of the latest advances in neuroscience using optogenetics.展开更多
文摘Although hunting in the north-eastern Atlantic forest of Brazil began more than 500 years ago, no study to date has evaluated its impacts on the region’s mammalian fauna. For one year we carried out diurnal and nocturnal surveys using the Line Transect method in seven forest fragments varying from 7.32 ha to 469.76 ha, within a 4000 ha forest island archipelago, in Pernambuco State, Atlantic forest of northeastern Brazil. We calculated species density, population size, biomass and synergetic biomass, and recorded direct and indirect human impacts along the study transects. We recorded 44 mammalian species, of which 45.5% (n = 20) went extinct through hunting. The smallest forest fragment had the lowest richness, diversity, population size, and total biomass. It also had no synergetic biomass. The largest fragment had the highest richness, total density, and population size. There was a statistically significant relationship between fragment area and number of gunshots heard and suspended hunting platforms found;between population size and gunshots heard, suspended hunting platforms, free-roaming and feral dogs, and between total density and free-roaming and feral dogs. After more than 500 years of colonization hunting is still devastating, with larger fragments being linked to more hunters. Higher mammal abundances attracted more free-roaming and feral dogs, which have adapted to hunt wildlife on their own. Unless we protect every single forest fragment and create sustainable landscapes, we will not be able to save this hotspot’s hotspot.
基金supported by the National Natural Science Foundation of China (32125005, 32361133559)the Institute of Zoology,Chinese Academy of Sciences (2023IOZ0104)+2 种基金the Third Xinjiang Scientific Expedition Program (Grant No. 2022xjkk0800)the CAS-TWAS President’s Fellowship programme (BB)The Environment Agency Abu Dhabi (EAD) funded the project under a MOU with Mongolia’s Ministry of Environment and Green Development (MEGD)
文摘Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis, we evaluated the influence of small mammal prey—present in 95% of pellets—on the reproductive performance of the sakers. In Mongolia, three species comprised 95% of the identified small mammals: Mongolian Gerbil (Meriones unguiculatus, 39%), Brandt's Vole (Lasiopodomys brandtii, 49%) and Daurian Pika (Ochotona dauurica, 7%). We found a strong positive association between the proportion of small mammals in the diet and key breeding parameters of sakers. Clutch size, fledged brood sizes, and nest success all increased with a mammal-rich diet. Earlier laying was also linked to higher small mammal intake and was independently associated with improved breeding outcomes. These findings highlight a critical role of small mammal prey in shaping the reproductive success of sakers. Conserving and restoring grassland habitats that support abundant prey populations is essential for sustaining saker populations and achieving long-term conservation goals.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1A2C201017812)support of‘R&D Program for Forest Science Technology(Project No.2022461B10-2424-0201)’provided by Korea Forest Service(Korea Forestry Promotion Institute)。
文摘Mammal distribution is shaped by different ecological and anthropogenic factors,and the pattern varies depending on their sensitivity thresholds,food and habitat preferences,ecological roles,and physical traits.The present study investigated the influence of ecological and anthropogenic factors on the distribution of mammal species communities across different trophic levels and body sizes in Myanmar's Htamanthi Wildlife Sanctuary(HWS).The values of mammal characteristics,ecological,and anthropogenic factors were analyzed in ArcMap software.Most of the large and small sized mammals,whose distribution decreases with elevation,were observed near the main streams.Across mammal tropic levels,the omnivores and herbivores were mostly observed farther from gold mining sites.In terms of forage plant effect on mammal community,floral forage plants and the presence of climber negatively affected mammal species across different trophic levels.Moreover,presence of resin trees also has a substantial impact on the distribution of medium-large animals and omnivorous mammals as trophic niche factors.Overall,our findings highlight the crucial role that ecological and anthropogenic factors play in shaping mammal distribution in the HWS.This underscores the importance of simultaneously conserving both habitat and mammal diversity in HWS,especially in the face of a changing climate and environment.
基金National Natural Science Foundation of China(30070679)the Natural Science Foundation of Hubei Province(2004ABA138)+1 种基金the Key Technology R&D Programme Foundation of Hubei Province(2002AA301C43)the Hubei Health Bureau Research Programme Foundation(NX200427)
文摘Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that： 1 ） although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution （ 15 species were dispersed over three zones and two species over two zones） , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2） whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3）the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4） in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas.
基金This project was supported by the Natural Science Foundation of China(30460125)
文摘An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders （Rodentia, Insectivora, Scandentia and Carnivora）, while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts.
基金funded by the Department of Science and Technology(DST),Government of Indiafunding support by the Science and Engineering Research Board(SERB),New Delhi(No.SR/FTP/ES-49/2012).
文摘In recent years,explosion of research in the early Tertiary mammals of India has attracted widespread interest because of the importance of this fauna in understanding biogeographic origins,early evolution,and dispersal patterns of several modern mammal orders as well for its paleogeographic implications.Although Paleocene mammals are yet to be discovered in the Indian subcontinent,Indian Early Eocene mammal faunas are now becoming increasingly important in debates concerning the origins of several modern terrestrial orders.
基金Doctoral Research Fund of Mudanjiang Teachers College,Grant/Award Number:No.1002319042The filing project of Heilongjiang Education Department,Grant/Award Number:1354MSYTD024Ancell-Teicher Research Foundation for Genetic and Molecular Evolution.
文摘Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could exert hypoxic stresses such as oxidative damage on organisms living in these environments.In order to cope with these stresses,organisms have evolved specific strategies to adapt to hypoxia,including changes in physiology,gene expression regulation,and genetic mutations.Here,we review how mammals have adapted to the three high-altitude plateaus of the world,the limited oxygen dissolved in deep water habitats,and underground tunnels,with the aim of better understanding the adaptation of mammals to hypoxia.
基金supported by grants from DBT,DST,UGC-CAS,New Delhi,India
文摘Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement （REM） sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to sur- face at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately -90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin＇s theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.
基金supported by the National Natural Science Foundation of China(32270442,31872219,31370401,32030011,31630071,31772448)National Key Research and Development Program of China(2022YFF1301602)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_1747,KYCX23_1740)。
文摘High-altitude and marine mammals inhabit distinct ecosystems but share a common challenge:hypoxia.To survive in low-oxygen environments,these species have evolved similar phenotypic pulmonary adaptations,characterized by a high density of elastic fibers.In this study,we explored the molecular mechanisms underlying these adaptations,focusing on pulmonary fibrosis and hypoxia tolerance through comparative genomics and convergent evolution analyses.We observed significant expansions and contractions in certain gene families across both high-altitude and marine mammals,closely associated with processes involved in pulmonary fibrosis.Notably,members of the keratin gene family,such as KRT17 and KRT14,appear to be associated with the development of the dense elastic fiber phenotype observed in the lungs of hypoxia-tolerant mammals.Through selection pressure and amino acid substitution analyses,we identified multiple genes exhibiting convergent accelerated evolution,positive selection,and amino acid substitution in these species,associated with adaptation to hypoxic environments.Specifically,the convergent evolution of ZFP36L1,FN1,and NEDD9 was found to contribute to the high density of elastic fibers in the lungs of both high-altitude and marine mammals,facilitating their hypoxia tolerance.Additionally,we identified convergent amino acid substitutions and gene loss events associated with sperm development,differentiation,and spermatogenesis,such as amino acid substitutions in SLC26A3 and pseudogenization of CFAP47,as confirmed by PCR.These genetic alterations may be linked to changes in the reproductive capabilities of these animals.Overall,this study offers novel perspectives on the genetic and molecular adaptations of high-altitude and marine mammals to hypoxic environments,with a particular emphasis on pulmonary fibrosis.
文摘Mammalian surveys are vital tools for effective managements and conservation strategies. A survey was conducted to investigate the species composition, relative abundance and to determine their major threats in Weyngus Forest, West Gojjam Zone, Amhara Region, Ethiopia. The data were collected from April 2020 to June 2020. Transect method and subjective interviews were used to collect data for the study. A total of 11 species of medium and large sized mammals belonging to six orders and eight families were recorded by direct and indirect evidences. Porcupine (Hystrix cristata), Vervet monkey (Chlorocebus aethiops), and Coloubus monkey (Colobus guereza) were among the medium-sized mammals while, Spotted hyena (Crocuta crocuta), Bushbuck (Tragelaphus scriptus) and Common duiker (Sylvicapra grimmia) were among the large-sized mammals recorded in the study area. Vervet monkey has been the most frequently observed species, whereas spotted hyena was observed less often. Simpson’s Similarity Index (SI) showed a significant overlap of mammalian species composition between scrubland and natural forest (SI = 0.62). Illegal logging of trees for fuel wood, agricultural land expansion, illegal hunting and land degradation were the main threats of mammals in the study area. Community participation and awareness creation are highly recommended to limit the impact of anthropogenic activities threatening wildlife.
文摘Since the last comprehensive review of the then stateof-the-art progress in paleomammalogy in 2010,there has been substantial further advances in understanding the middle ear development and phylogeny of Mesozoic mammals,evolution of early primates,and so on.The post-dentary bone morphologies of two Jurassic mammaliaforms,Dianoconodon youngi and Feredocodon chowi,demonstrate the detachment mechanism of post-dentary bones from the dentary and the eventual breakdown of the Meckel’s cartilage during the evolution of mammaliaforms.The middle ear of the Early Cretaceous Liaoconodon hui defines the transitional mammalian middle ear.The Creataceous stem therian Origolestes lii displays the decoupling of hearing and chewing apparatuses and functions.In addition,the discovery of Ambolestes zhoui,an Early Cretaceous eutherian,demonstrates that Sinodelphys,the oldest purported marsupial,is actually a eutherian.The early Eocene haplorrhine primate,Archicebus achilles,resurrects the possibility that Asia was an important stage for early primate evolution.Not only has knowledge concerning these topics been further deepened,but new knowledge has also been acquired concerning Late Cenozoic herbivores and primates in paleomammalogy on the basis of these new discoveries.
文摘Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preservedhairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao,western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and lifehabits of Mesozoic symmetrodont mammals.
基金supported by the Sino-Africa Joint Research Centre,Chinese Academy of Sciences(SAJC201612)
文摘The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted on Afromontane ecosystems have compared the altitudinal patterns of small mammal diversity. We investigated the species diversity and abundance of non-volant small mammals(hereafter ‘small mammals')on Mt. Kenya, the second tallest mountain in Africa,using a standard sampling scheme. Nine sampling transects were established at intervals of 200 m on the eastern(Chogoria) and western(Sirimon) slopes.A total of 1 905 individuals representing 25 species of small mammals were trapped after 12 240 trap-nights.Abundance was highest at mid-elevations on both slopes.However, species richness and their distribution patterns differed between the two slopes. More species were recorded on Chogoria(24) than on Sirimon(17). On Chogoria, species richness was higher at mid-high elevations, with a peak at mid-elevation(2 800 m a.s.l.),whereas species richness showed little variation on the Sirimon slope. These results indicate that patterns of species diversity can differ between slopes on the same mountain. In addition, we extensively reviewed literature on Mt. Kenya's mammals and compiled a comprehensive checklist of 76 mammalian species. However, additional research is required to improve our understanding of smal mammal diversity in mountain habitats in Africa.
基金supported by grants from Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund 2007–2013(BFU2014-56300-P and BFU-2017-87079-P)a fellowship from EMBO(7010,to DRS)+3 种基金a grant from the Xunta de Galicia(2016-PG008,to ABI)a grant from the crowdfunding platform Precipita(FECYT Spanish Ministry of Economy and Competitiveness 2017-CP081)
文摘In mammals, spinal cord injury (SCI) is a devastating event that can lead to a permanent loss of motor, sensory and autonomic functions below the site of injury. In the last years, the role of different neurotransmitter systems on regeneration and recovery from SCI has been deciphered. For example, studies in lampreys have shown that neurotransmitters play a key role in modulating the survival and regeneration of brainstem descending neurons after SCI (Romaus-Sanjurjo et al., 2018;Sobrido-Camean et al., 2018).
基金Supported by the French ANR CERoPath project(number ANR 07 BDIV 012)the French ANR BiodivHealthSEA project(number ANR 11 CPEL.002)
文摘In this article,authors review the current knowledge of Bartonella infection in small mammals including rodents,insectivores,bats and exotic small mammal pets and their vectors in Asia.Species of Bartonella are Gram-negative intracellular bacteria that infect erythrocytes of various mammalian and non-mammalian animals and mainly transmitted by blood sucking arthropod vectors.The genus Bartonella includes several species of important human diseases with severe clinical signs.Several new Bartonella species were isolated from rodents and other small mammals,and from human patients in Asia.Bartonella species are identified using standard polymerase chain reaction amplification and a sequencing targeting two housekeeping genes(glt.A and rpoB) and the internal transcribed spacer fragment.Authors also discuss the implications in term of potential emerging zoonotic diseases.
基金supported by the International Cooperation Program of MST of China(2009DFB20580)the Major Basic Research Project of MST of China(Grant No: 2006CB806400)+1 种基金Special Basic Research Project(Grant No:2007FY110200)of MST of Chinathe IVPP Project(Grant No:KA209508)
文摘The current and dominant theory about the origin of modern humans is the out-of-Africa hypothesis, which asserts that populations of Homo sapiens left Africa 100,000 years ago and replaced indigenous populations of humans in Eurasia. Many scholars equated the out-of-Africa dispersal of humans with paleoenvironmental changes. However, until now, few have paid special attention to the faunal data and whether or not faunal patterns are supportive of the popular theory. Recent comparative study of the Chinese fauna shows that the communication of faunas between Africa and East Asia could have occurred during the Neogene, but it was very limited during the Pleistocene. In the Chinese Quaternary fauna, only 16% of the genera are also present in the sub-Saharan African fauna. There is also no element among the dominant taxa of the Chinese Quaternary fauna which can be related to the African fauna. There is no reliable proof for the existence of Hippopotamus and Giraffa, as well as Panthera leo, during the Quaternary in China. Two controversial taxa are Acinonyx and Crocuta, about which there is still argument concerning their species identification in Eurasia. It is possible that both of the genera have co-specific taxa in Africa and Eurasia. Although the two genera are confined to Africa today, they did have a long evolutionary history in China. For the Out of Africa hypothesis for Homo sapiens, the implications of the limited faunal interchanges between China and Africa are not completely clear yet.
基金supported by the National Natural Science Foundation of China(NSFC)(31900310 to R.T.)Key Project of the NSFC(32030011 and 31630071 to G.Y.)+2 种基金NSFC(31950410545 to I.S.)Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Jiangsu Specially-Appointed Professors Program(to I.S.)。
文摘Many mammals risk damage from oxidative stress stemming from frequent dives(i.e., cycles of ischemia/reperfusion and hypoxia/reoxygenation),high altitude and subterranean environments, or powered flight. Purine metabolism is an essential response to oxidative stress, and an imbalance between purine salvage and de novo biosynthesis pathways can generate damaging reactive oxygen species(ROS). Here, we examined the evolution of 117 purine metabolism-related genes to explore the accompanying molecular mechanisms of enhanced purine metabolism in mammals under high oxidative stress. We found that positively selected genes,convergent changes, and nonparallel amino acid substitutions are possibly associated with adaptation to oxidative stress in mammals. In particular, the evolution of convergent genes with c AMP and c GMP regulation roles may protect mammals from oxidative damage. Additionally, 32 genes were identified as under positive selection in cetaceans, including key purine salvage enzymes(i.e., HPRT1), suggesting improved re-utilization of non-recyclable purines avoid hypoxanthine accumulation and reduce oxidative stress. Most intriguingly, we found that six unique substitutions in cetacean xanthine dehydrogenase(XDH), an enzyme that regulates the generation of the ROS precursor xanthine oxidase(XO) during ischemic/hypoxic conditions, show enhanced enzyme activity and thermal stability and diminished XO conversion activity. These functional adaptations are likely beneficial for cetaceans by reducing radical oxygen species production during diving. In summary, our findings offer insights into the molecular and functional evolution of purine metabolism genes in mammalian oxidative stress adaptations.
基金supported by the National Basic Research Program of China (2011CB503700)
文摘Optogenetics is a newly-introduced technology in the life sciences and is gaining increasing attention.It refers to the combination of optical technologies and genetic methods to control the activity of specific cell groups in living tissue,during which high-resolution spatial and temporal manipulation of cells is achieved.Optogenetics has been applied to numerous regions,including cerebral cortex,hippocampus,ventral tegmental area,nucleus accumbens,striatum,spinal cord,and retina,and has revealed new directions of research in neuroscience and the treatment of related diseases.Since optogenetic tools are controllable at high spatial and temporal resolution,we discuss its applications in these regions in detail and the recent understanding of higher brain functions,such as reward-seeking,learning and memory,and sleep.Further,the possibilities of improved utility of this newly-emerging technology are discussed.We intend to provide a paradigm of the latest advances in neuroscience using optogenetics.
