Radiomics is a non-invasive method for extracting quantitative and higher-dimensional features from medical images for diagnosis.It has received great attention due to its huge application prospects in recent years.We...Radiomics is a non-invasive method for extracting quantitative and higher-dimensional features from medical images for diagnosis.It has received great attention due to its huge application prospects in recent years.We can know that the number of features selected by the existing radiomics feature selectionmethods is basically about ten.In this paper,a heuristic feature selection method based on frequency iteration and multiple supervised training mode is proposed.Based on the combination between features,it decomposes all features layer by layer to select the optimal features for each layer,then fuses the optimal features to form a local optimal group layer by layer and iterates to the global optimal combination finally.Compared with the currentmethod with the best prediction performance in the three data sets,thismethod proposed in this paper can reduce the number of features fromabout ten to about three without losing classification accuracy and even significantly improving classification accuracy.The proposed method has better interpretability and generalization ability,which gives it great potential in the feature selection of radiomics.展开更多
Aiming at the problems of short duration,low intensity,and difficult detection of micro-expressions(MEs),the global and local features of ME video frames are extracted by combining spatial feature extraction and tempo...Aiming at the problems of short duration,low intensity,and difficult detection of micro-expressions(MEs),the global and local features of ME video frames are extracted by combining spatial feature extraction and temporal feature extraction.Based on traditional convolution neural network(CNN)and long short-term memory(LSTM),a recognition method combining global identification attention network(GIA),block identification attention network(BIA)and bi-directional long short-term memory(Bi-LSTM)is proposed.In the BIA,the ME video frame will be cropped,and the training will be carried out by cropping into 24 identification blocks(IBs),10 IBs and uncropped IBs.To alleviate the overfitting problem in training,we first extract the basic features of the preprocessed sequence through the transfer learning layer,and then extract the global and local spatial features of the output data through the GIA layer and the BIA layer,respectively.In the BIA layer,the input data will be cropped into local feature vectors with attention weights to extract the local features of the ME frames;in the GIA layer,the global features of the ME frames will be extracted.Finally,after fusing the global and local feature vectors,the ME time-series information is extracted by Bi-LSTM.The experimental results show that using IBs can significantly improve the model’s ability to extract subtle facial features,and the model works best when 10 IBs are used.展开更多
Studies of the seasonal acclimatisation of behavioural and physiological processes usually focus on aquatic or semi-aquatic ectotherms and focus less effort on terrestrial ectotherms that experience more thermally het...Studies of the seasonal acclimatisation of behavioural and physiological processes usually focus on aquatic or semi-aquatic ectotherms and focus less effort on terrestrial ectotherms that experience more thermally heterogeneous environments. We conducted comparative studies and thermal acclimation experiments on the locomotion of the Chinese skink (Plestiodon chinensis) to test whether seasonal acclimatisation in locomotion exists in these terrestrial ectothermic vertebrates, and whether seasonal acclimatisation is predominantly induced by thermal environments. In natural populations, skinks ran faster during the summer season than during the spring season at high-test temperatures ranging from 27℃ to 36℃ but not at low-test temperatures ranging from 18℃ to 24℃. In contrast, the thermal acclimation experiments showed that the cold-acclimated skinks ran faster than the warm-acclimated skinks at the low- test temperatures but not at high-test temperatures. Therefore, the seasonal acclimatisation occurs to P chinensis, and may be induced by temperature as well as other factors like food availability, as indicated by the seasonal variation in the thermal dependence of locomotion, and the discrepancy between seasonal acclimatisation and thermal acclimation on locomotion.展开更多
Locomotor performance in lizards is strongly affected by structural habitat. Understanding this relationship allows us to predict species distributions across habitat types. However, little information is available ab...Locomotor performance in lizards is strongly affected by structural habitat. Understanding this relationship allows us to predict species distributions across habitat types. However, little information is available about the ecological role of the locomotion of multiocellated racerunner (Eremias multiocellata) in the desert steppe ecosystem of Inner Mongolia, China. Herein, we studied the effects of habitat structure on the locomotor performance of this lizard species in the field. We found that the sprint speed of this lizard declined significantly with increasing vegetation coverage. Manipulative experiments were further conducted to examine the effects of branch barriers and surface substrates on the sprint speed of the lizard. We found that the sprint speed was significantly influenced by the surface substrates and branch barriers, and there were no interactions between them. Branch barriers impeded sprint speed, and E. multiocellata showed better locomotor performance on sandy rather than loamy substrates. Our results indicate that E. multiocellata tends to occupy open areas with sandy substrates, but its locomotor performance is not closely associated with habitat preference.展开更多
Desertification is a serious ecological problem leading to significant biodiversity loss,but how desertification drives shifts in life history and fitness of animals remains understudied.To clarify whether habitat des...Desertification is a serious ecological problem leading to significant biodiversity loss,but how desertification drives shifts in life history and fitness of animals remains understudied.To clarify whether habitat desertification causes shifts in life history strategies,we compared ecological factors and reproductive traits of Phrynocephalus przewalskii from three different desertification habitats-fixed dune,semi-fixed dune and mobile dune of a semi-arid region of Inner Mongolia,at the eastern edge of Hobq Desert,China.Our results showed a significant shift in the egg size-number trade-off of P.przewalskii in response to desertification,with lizards from the mobile dune habitat producing smaller clutches of larger eggs than lizards from the fixed and semi-fixed dune habitats.This life history shift is likely adaptive and driven by abiotic factors(temperature and precipitation)rather than biotic factors(food availability and lizard population density).Our study demonstrates that habitat desertification drives the shift in egg size-number trade-off in a lizard and highlights the importance of exploring the life history responses of animals to habitat desertification as well as to other traditionally well-studied factors like temperature,especially in the context of future global clima te change.展开更多
Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Su...Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Successful captive breeding can provide individuals to be reintroduced into their natural habitat and help to restore the wild populations. Studying the mating behavior and parturition of these lizards in captivity will enable us understand how is this ancient species reproduction and optimize artificial reproduction protocol. We studied the mating behavior and parturition of Chinese crocodile lizards in captivity using video recordings at the Daguishan National Nature Reserve, China, from 2015 to 2017. We analyzed pre-copulation and copulation, which occurred in mid-March to late May from all studied years. Pre-copulation and copulation lasted on average 7.51(n=11) and 27.45(n=11) minutes, respectively. We found that large-bodied male lizards have longer copulation periods, a pattern seen in other lizard species. In the mating event, males always initiated sex, while the females were passive. The duration of parturition lasted 153.8 ± 26.8(n=46) minutes, and larger females had heavier clutches. In addition, even though Chinese crocodile lizards represent an ancient lizard clade with primitive characteristics, they still abide by the reproduction patterns seen in most other lizard species.展开更多
Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in d...Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in different habitats,from July to September 2020,we radio-tagged and tracked 15 individuals in each of sites distributed at high(3600 m)and low(2600 m)altitudes on the Dangjin Mountain,Gansu Province,northwest China.We calculated home range size using the 100%minimum convex polygon method,and analyzed the influence of inherent lizard characteristics and external environmental factors.Our results revealed that for both high-and lowaltitude lizard populations,the sizes of home ranges were positively correlated with lizard body mass.Moreover,after eliminating the effect of body mass as a covariable,we established that the home ranges of high-altitude lizards(5255.1±1103.8 m^(2))were larger than those of the low-altitude lizards(2208.1±348.7 m^(2)).Lizards in the high-altitude population were also characterized by longer daily suitable activity times and spent significantly more time in full sunlight than those in the low-altitude population.Furthermore,the food resources for lizards in low-altitude habitats were more abundant than those in high-altitude habitats In conclusion,we established that P.vlangalii lizards inhabiting high-altitude sites had larger home ranges than conspecific lizards distributed at a lower altitude,which was associated not only with endogenous factors,such as body mass,but also with habitat-related environmental factors,such as the quality of thermal resources and availability of food.展开更多
Pattern synthesise of antenna arrays is usually complicated optimization problems,while evolutionary algorithms(EAs)are promising in solving these problems.This paper does not propose a new EA,but does construct a new...Pattern synthesise of antenna arrays is usually complicated optimization problems,while evolutionary algorithms(EAs)are promising in solving these problems.This paper does not propose a new EA,but does construct a new form of optimization problems.The new optimization formulation has two differences from the common ones.One is the objective function is the field error between the desired and the designed,not the usual amplitude error between the desired and the designed.This difference is beneficial to decrease complexity in some sense.The second difference is that the design variables are changed as phases of desired radiation field within shaped-region,instead of excitation parameters.This difference leads to the reduction of the number of design variables.A series of synthesis experiments including equally and unequally spaced linear arrays with different pattern shape requirements are applied,and the effectiveness and advantages of the proposed new optimization problems are validated.The results show that the proposing a new optimization formulation with less complexity is as significant as proposing a new algorithm.展开更多
Environmental changes along an altitudinal gradient can facilitate the differentiation of life-history features in ectothermic species,but little attention has been devoted to the reciprocal influence of altitude and ...Environmental changes along an altitudinal gradient can facilitate the differentiation of life-history features in ectothermic species,but little attention has been devoted to the reciprocal influence of altitude and alpine slope directionality on life-history variation.According to life-history theory,increased environmental stress causes a change in reproductive allocation from number to quality of offspring,as well as a stronger trade-off between size and number of offspring.To clarify the influence of environmental pressures on the life-history features of the Qinghai toad-headed lizard Phrynocephalus vlangalii along an altitudinal cline,we surveyed late pregnant females from 3 populations of low(2,600 m),middle(3,400 m),and high(3,600 m)elevations in the Dangjin Mountain of Gansu,China from July to October 2019,and compared their inter-population differences in maternal body size,reproductive characteristics,offspring growth,and locomotor performance.Because of lower temperatures,higher humidity,and lower light intensity caused by slope aspect and altitude,the middle-altitude region experienced stronger environmental stress than the high-and low-altitude regions.Our results showed that females were larger at middle-and high-altitude sites and smaller at the low-altitude site,following Bergmann’s rule.We also found that females from low-altitude population gave birth earlier than those from the middle and high altitudes.Our results showed a shift in the offspring size-number trade-off of P.vlangalii in response to colder and harsher environments,with lizards from the alpine steppe(i.e.the middle-and high-altitude habitats)producing fewer but larger offspring than those from the warm steppe(i.e.the low-altitude habitat).Low-altitude juveniles grew faster than high-altitude ones,but at the same rates as middle-altitude juveniles.This result demonstrates that the growth of P.vlangalii was associated with temperature and light intensity.Our findings contribute to enhancing our understanding of the altitudinal variation in life-history features of plateau ectotherms and their phenotypic plasticity or local adaptation.展开更多
Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age ...Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age at first reproduction,litter size and adult life expectancy)were collected from 121 Hainan Eld’s deer(Cervus eldi hainanus Thomas,1918),an in situ herd of an endemic,rare and endangered cervid inhabiting Bangxi Natural Reserve of Hainan Island,from 1990 to 2002.First,we constructed a dynamic life table to analyze the life history pattern of the population,which showed that the difference between the average lifespan of males and females was not significant(P>0.05),and that the difference between the average lifespan of the whole Hainan Eld’s deer population and that of other Eld’s deer populations living in South Asia(P>0.05),North America(P>0.05)and Europe(P>0.05)was not significant.Second,we used individual reproductive success or number of offspring of a male over its lifetime to estimate male individual fitness.Statistic analysis showed that male individual fitness was not significantly correlated with total antler velvet mass.Third,we used the population intrinsic rate of increase to measure population fitness,and population fitness of Hainan Eld’s deer was compared with similar indexes of 5 other cervid species.Hainan Eld’s deer population fitness index was 0.012,the second lowest value relative to other cervids.Results indicated that this rare species is still endangered and is in need of additional protection.展开更多
基金Major Project for New Generation of AI Grant No.2018AAA0100400)the Scientific Research Fund of Hunan Provincial Education Department,China(Grant Nos.21A0350,21C0439,22A0408,22A0414,2022JJ30231,22B0559)the National Natural Science Foundation of Hunan Province,China(Grant No.2022JJ50051).
文摘Radiomics is a non-invasive method for extracting quantitative and higher-dimensional features from medical images for diagnosis.It has received great attention due to its huge application prospects in recent years.We can know that the number of features selected by the existing radiomics feature selectionmethods is basically about ten.In this paper,a heuristic feature selection method based on frequency iteration and multiple supervised training mode is proposed.Based on the combination between features,it decomposes all features layer by layer to select the optimal features for each layer,then fuses the optimal features to form a local optimal group layer by layer and iterates to the global optimal combination finally.Compared with the currentmethod with the best prediction performance in the three data sets,thismethod proposed in this paper can reduce the number of features fromabout ten to about three without losing classification accuracy and even significantly improving classification accuracy.The proposed method has better interpretability and generalization ability,which gives it great potential in the feature selection of radiomics.
基金supported by the National Natural Science Foundation of Hunan Province,China(Grant Nos.2021JJ50058,2022JJ50051)the Open Platform Innovation Foundation of Hunan Provincial Education Department(Grant No.20K046)The Scientific Research Fund of Hunan Provincial Education Department,China(Grant Nos.21A0350,21C0439,19A133).
文摘Aiming at the problems of short duration,low intensity,and difficult detection of micro-expressions(MEs),the global and local features of ME video frames are extracted by combining spatial feature extraction and temporal feature extraction.Based on traditional convolution neural network(CNN)and long short-term memory(LSTM),a recognition method combining global identification attention network(GIA),block identification attention network(BIA)and bi-directional long short-term memory(Bi-LSTM)is proposed.In the BIA,the ME video frame will be cropped,and the training will be carried out by cropping into 24 identification blocks(IBs),10 IBs and uncropped IBs.To alleviate the overfitting problem in training,we first extract the basic features of the preprocessed sequence through the transfer learning layer,and then extract the global and local spatial features of the output data through the GIA layer and the BIA layer,respectively.In the BIA layer,the input data will be cropped into local feature vectors with attention weights to extract the local features of the ME frames;in the GIA layer,the global features of the ME frames will be extracted.Finally,after fusing the global and local feature vectors,the ME time-series information is extracted by Bi-LSTM.The experimental results show that using IBs can significantly improve the model’s ability to extract subtle facial features,and the model works best when 10 IBs are used.
基金supported by grants from the National Natural Science Foundation of China (30770274)the "One Hundred Talents Program" of the Chinese Academy of Sciences for W. G. DU
文摘Studies of the seasonal acclimatisation of behavioural and physiological processes usually focus on aquatic or semi-aquatic ectotherms and focus less effort on terrestrial ectotherms that experience more thermally heterogeneous environments. We conducted comparative studies and thermal acclimation experiments on the locomotion of the Chinese skink (Plestiodon chinensis) to test whether seasonal acclimatisation in locomotion exists in these terrestrial ectothermic vertebrates, and whether seasonal acclimatisation is predominantly induced by thermal environments. In natural populations, skinks ran faster during the summer season than during the spring season at high-test temperatures ranging from 27℃ to 36℃ but not at low-test temperatures ranging from 18℃ to 24℃. In contrast, the thermal acclimation experiments showed that the cold-acclimated skinks ran faster than the warm-acclimated skinks at the low- test temperatures but not at high-test temperatures. Therefore, the seasonal acclimatisation occurs to P chinensis, and may be induced by temperature as well as other factors like food availability, as indicated by the seasonal variation in the thermal dependence of locomotion, and the discrepancy between seasonal acclimatisation and thermal acclimation on locomotion.
基金performed under the approval from the Animal Ethics Committee at the Institute of Zoology,Chinese Academy of Sciences(IOZ14001)
文摘Locomotor performance in lizards is strongly affected by structural habitat. Understanding this relationship allows us to predict species distributions across habitat types. However, little information is available about the ecological role of the locomotion of multiocellated racerunner (Eremias multiocellata) in the desert steppe ecosystem of Inner Mongolia, China. Herein, we studied the effects of habitat structure on the locomotor performance of this lizard species in the field. We found that the sprint speed of this lizard declined significantly with increasing vegetation coverage. Manipulative experiments were further conducted to examine the effects of branch barriers and surface substrates on the sprint speed of the lizard. We found that the sprint speed was significantly influenced by the surface substrates and branch barriers, and there were no interactions between them. Branch barriers impeded sprint speed, and E. multiocellata showed better locomotor performance on sandy rather than loamy substrates. Our results indicate that E. multiocellata tends to occupy open areas with sandy substrates, but its locomotor performance is not closely associated with habitat preference.
基金supported by grants from the National Natural Science Foundation of China (31861143023, 31821001, and 31570526)China’s Biodiversity Observation Network (Sino-BON)
文摘Desertification is a serious ecological problem leading to significant biodiversity loss,but how desertification drives shifts in life history and fitness of animals remains understudied.To clarify whether habitat desertification causes shifts in life history strategies,we compared ecological factors and reproductive traits of Phrynocephalus przewalskii from three different desertification habitats-fixed dune,semi-fixed dune and mobile dune of a semi-arid region of Inner Mongolia,at the eastern edge of Hobq Desert,China.Our results showed a significant shift in the egg size-number trade-off of P.przewalskii in response to desertification,with lizards from the mobile dune habitat producing smaller clutches of larger eggs than lizards from the fixed and semi-fixed dune habitats.This life history shift is likely adaptive and driven by abiotic factors(temperature and precipitation)rather than biotic factors(food availability and lizard population density).Our study demonstrates that habitat desertification drives the shift in egg size-number trade-off in a lizard and highlights the importance of exploring the life history responses of animals to habitat desertification as well as to other traditionally well-studied factors like temperature,especially in the context of future global clima te change.
基金financially support by the National Key Research & Development Program of China (2016YFC0503200)the Natural Science Foundation of China (31760623)the Financial Project of State Forestry Administration (V2130211)
文摘Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Successful captive breeding can provide individuals to be reintroduced into their natural habitat and help to restore the wild populations. Studying the mating behavior and parturition of these lizards in captivity will enable us understand how is this ancient species reproduction and optimize artificial reproduction protocol. We studied the mating behavior and parturition of Chinese crocodile lizards in captivity using video recordings at the Daguishan National Nature Reserve, China, from 2015 to 2017. We analyzed pre-copulation and copulation, which occurred in mid-March to late May from all studied years. Pre-copulation and copulation lasted on average 7.51(n=11) and 27.45(n=11) minutes, respectively. We found that large-bodied male lizards have longer copulation periods, a pattern seen in other lizard species. In the mating event, males always initiated sex, while the females were passive. The duration of parturition lasted 153.8 ± 26.8(n=46) minutes, and larger females had heavier clutches. In addition, even though Chinese crocodile lizards represent an ancient lizard clade with primitive characteristics, they still abide by the reproduction patterns seen in most other lizard species.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA20050201)the National Natural Science Fund of China (31861143023).
文摘Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in different habitats,from July to September 2020,we radio-tagged and tracked 15 individuals in each of sites distributed at high(3600 m)and low(2600 m)altitudes on the Dangjin Mountain,Gansu Province,northwest China.We calculated home range size using the 100%minimum convex polygon method,and analyzed the influence of inherent lizard characteristics and external environmental factors.Our results revealed that for both high-and lowaltitude lizard populations,the sizes of home ranges were positively correlated with lizard body mass.Moreover,after eliminating the effect of body mass as a covariable,we established that the home ranges of high-altitude lizards(5255.1±1103.8 m^(2))were larger than those of the low-altitude lizards(2208.1±348.7 m^(2)).Lizards in the high-altitude population were also characterized by longer daily suitable activity times and spent significantly more time in full sunlight than those in the low-altitude population.Furthermore,the food resources for lizards in low-altitude habitats were more abundant than those in high-altitude habitats In conclusion,we established that P.vlangalii lizards inhabiting high-altitude sites had larger home ranges than conspecific lizards distributed at a lower altitude,which was associated not only with endogenous factors,such as body mass,but also with habitat-related environmental factors,such as the quality of thermal resources and availability of food.
基金Major Project for New Generation of AI under Grant 2018AAA0100400in part by Scientific Research Fund of Hunan Provincial Education Department of China under Grant 21A0350,21C0439+4 种基金in part by the National Natural Science Foundation of China under Grant 61673355in part by the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)under Grant CUGGC02in part by the Hubei Provincial Natural Science Foundation of China under Grant 2015CFA010in part by the high-performance computing platform of the China University of Geosciencesin part by the 111 projectunder Grant B17040.
文摘Pattern synthesise of antenna arrays is usually complicated optimization problems,while evolutionary algorithms(EAs)are promising in solving these problems.This paper does not propose a new EA,but does construct a new form of optimization problems.The new optimization formulation has two differences from the common ones.One is the objective function is the field error between the desired and the designed,not the usual amplitude error between the desired and the designed.This difference is beneficial to decrease complexity in some sense.The second difference is that the design variables are changed as phases of desired radiation field within shaped-region,instead of excitation parameters.This difference leads to the reduction of the number of design variables.A series of synthesis experiments including equally and unequally spaced linear arrays with different pattern shape requirements are applied,and the effectiveness and advantages of the proposed new optimization problems are validated.The results show that the proposing a new optimization formulation with less complexity is as significant as proposing a new algorithm.
基金Thiswork was supported,by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20050201)the National Natural Science Fund of China(31861143023).
文摘Environmental changes along an altitudinal gradient can facilitate the differentiation of life-history features in ectothermic species,but little attention has been devoted to the reciprocal influence of altitude and alpine slope directionality on life-history variation.According to life-history theory,increased environmental stress causes a change in reproductive allocation from number to quality of offspring,as well as a stronger trade-off between size and number of offspring.To clarify the influence of environmental pressures on the life-history features of the Qinghai toad-headed lizard Phrynocephalus vlangalii along an altitudinal cline,we surveyed late pregnant females from 3 populations of low(2,600 m),middle(3,400 m),and high(3,600 m)elevations in the Dangjin Mountain of Gansu,China from July to October 2019,and compared their inter-population differences in maternal body size,reproductive characteristics,offspring growth,and locomotor performance.Because of lower temperatures,higher humidity,and lower light intensity caused by slope aspect and altitude,the middle-altitude region experienced stronger environmental stress than the high-and low-altitude regions.Our results showed that females were larger at middle-and high-altitude sites and smaller at the low-altitude site,following Bergmann’s rule.We also found that females from low-altitude population gave birth earlier than those from the middle and high altitudes.Our results showed a shift in the offspring size-number trade-off of P.vlangalii in response to colder and harsher environments,with lizards from the alpine steppe(i.e.the middle-and high-altitude habitats)producing fewer but larger offspring than those from the warm steppe(i.e.the low-altitude habitat).Low-altitude juveniles grew faster than high-altitude ones,but at the same rates as middle-altitude juveniles.This result demonstrates that the growth of P.vlangalii was associated with temperature and light intensity.Our findings contribute to enhancing our understanding of the altitudinal variation in life-history features of plateau ectotherms and their phenotypic plasticity or local adaptation.
基金Funding for this study was provided by National Nature Science Foundation of China (30430120). We followed guidelines for the use of animals in research as pub-lished by the journal Animal Behaviour. We thank staff at Hainan Datian National Nature Reserve for assistance during our field research with special thanks to Li Shanyuan and Xing Yichang who graciously contributed their time and effort during this study.
基金We are grateful to Mr Youfeng Zheng and Mr Daliang Fu of the Bangxi Natural Reserve of Hainan Province for their help in the course of field data collection.We sincerely thank anonymous reviewers for comments and suggestions that helped to improve the manuscript.The research was supported by the Key National Natural Science Foundation(Fund No.30430120)China Postdoctoral Fund No.20070410635 and the Introduction of Higher-Level-Talents Foundation of Central South University of Forestry and Technology(Fund No.101-0630).
文摘Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age at first reproduction,litter size and adult life expectancy)were collected from 121 Hainan Eld’s deer(Cervus eldi hainanus Thomas,1918),an in situ herd of an endemic,rare and endangered cervid inhabiting Bangxi Natural Reserve of Hainan Island,from 1990 to 2002.First,we constructed a dynamic life table to analyze the life history pattern of the population,which showed that the difference between the average lifespan of males and females was not significant(P>0.05),and that the difference between the average lifespan of the whole Hainan Eld’s deer population and that of other Eld’s deer populations living in South Asia(P>0.05),North America(P>0.05)and Europe(P>0.05)was not significant.Second,we used individual reproductive success or number of offspring of a male over its lifetime to estimate male individual fitness.Statistic analysis showed that male individual fitness was not significantly correlated with total antler velvet mass.Third,we used the population intrinsic rate of increase to measure population fitness,and population fitness of Hainan Eld’s deer was compared with similar indexes of 5 other cervid species.Hainan Eld’s deer population fitness index was 0.012,the second lowest value relative to other cervids.Results indicated that this rare species is still endangered and is in need of additional protection.