Objective The aim of this study is to estimate the prevalence of autism spectrum disorder (ASD) among 18-36 month old children in the Tianjin Municipality of China, and to identify early signs of autistic children a...Objective The aim of this study is to estimate the prevalence of autism spectrum disorder (ASD) among 18-36 month old children in the Tianjin Municipality of China, and to identify early signs of autistic children and the predictability of each individual symptom. Methods A total of 8 000 children were screened to do a questionnaire based on CHAT modified to include more early signs of autism at the age of 28-36 months. Then the at-risk children were reexamined 1.5 years later and ASD children were identified based on DSM-IV. Early signs of autism were analyzed retrospectively by using discriminant function analysis performed among ASD children, children not followed up and children followed up but failing to meet ASD criteria. Results Three hundred and sixty seven children were screened as being at-risk to ASD, and 22 of them were identified as having ASD in the subsequent diagnosis. The prevalence of ASD was 27.5 per 10 000 in Tianjin of China with a male to female ratio of 4:1. Items addressing social interactions and communications had higher predictability than other items to distinguish autistic children from non-autistic ones. Pretend play, functional play, showing and reading parents' facial expressions distinguished autistic children from those not followed up, nevertheless those followed up but failing to meet ASD criteria were not included.Conclusion The prevalence of ASD found in our study was lower than that reported in some studies by western researchers. Autism has its specific symptoms, such as deficits in social awareness, social relatedness, and social referencing.展开更多
Background: Individuality in vocalizations may provide an effective tool for surveying populations of the Common Cuckoo(Cuculus canorus) but there remains few data on which technique to use to identify individuality. ...Background: Individuality in vocalizations may provide an effective tool for surveying populations of the Common Cuckoo(Cuculus canorus) but there remains few data on which technique to use to identify individuality. In this research, we compared the within-and between-individual variation in cuckoo calls using two different analytical methods, and discuss the feasibility of using call individuality to count male cuckoos within a population.Methods: We recorded vocalization from 13 males, and measured 15 spectro-temporal variables for each call. The majority of these call variables(n = 12) have greater variation between individuals than within individual. We first calculated the similarity(Pearson's R) for each paired calls in order to find a threshold that could distinguish calls emitted from the same or different males, and then counted the number of males based on this distinction. Second, we used the more widely accepted technique of discriminant function analysis(DFA) to identify individual male cuckoos, and compared the correct rate of classifying individuals between the two analytical methods.Results: Similarity of paired calls from the same male was significantly higher than from different males. Under a relatively broad threshold interval, we achieved a high(>90%) correct rate to distinguish calls and an accurate estimate of male numbers. Based on banded males(n = 3), we found the similarity of paired calls from different days was lower when compared with paired calls from the same day, but this change did not obscure individual identification, as similarity values of paired calls from different days were still larger than the threshold used to distinguish calls from the same or different males. DFA also yielded a high rate(91.9%) of correct classification of individuals.Conclusions: Our study suggests that identifying individual vocalizations can form the basis of an appropriate survey method for counting male cuckoos within a population, provided the performance of different analytical techniques are compared.展开更多
Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments for...Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments formed in different marine(with normal and reduced salinity),brackish,and freshwater environments,depending on the development stage of the Pannonian Basin System.Carbonate minerals,clay minerals and quartz are the main constituents of all pelitic sedimentary rocks,except in those from Moslavacka Gora Mt in which carbonate minerals are not present.Feldspars,pyrite,opal-CT,and hematite are present as minor constituents in some rocks.Besides calcite,dependent on the sedimentary environment and diagenetic changes,high-magnesium calcite,aragonite,dolomite and ankerite/Cadolomite are also present.Smectite or illite-smectite is the main clay minerals in the samples.Minor constituents,present in almost all samples,are detrital illite and kaolinite.In some samples chlorite is also present in a low amount.Major elements,trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust(UCC).The contents of major and trace elements as well as SiO2/Al2O3,K2O/Al2O3,Na2O/K2O,Eu/Eu*,La/Sc,Th/Sc,La/Co Th/Co,Th/Cr,Ce/Ce* and LREE/HREE ratios,show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic(silicic),i.e.felsic rocks.展开更多
Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits ...Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits in the flyway have been assigned to melanuroides.However,a larger-bodied subspecies,bohaii,has recently been discovered in the flyway.As a result,the occurrence of Black-tailed Godwits in the flyway needs to be reconsidered such that the specific distribution of each subspecies becomes known.To this end,we developed a simple discriminant function to assign individuals to subspecies based on their bill and wing length.Cross-validation with individuals known to be bohaii or melanuroides,based on molecular analysis,showed the developed function to be 97.7%accurate.When applied to measurements of godwits captured at 22 sites across 9 countries in East-Southeast Asia and Australia,we found that bohaii and melanuroides occurred at most sites and overlapped in their distribution from Kamchatka to Australia.We examined photos from all along the flyway to verify this surprising result,confirming that both subspecies co-occur in most locations.Based on these results,we hypothesise that bohaii and melanuroides from the west of their breeding ranges mostly migrate over Chinese mainland.Birds of both subspecies from the east of their ranges are expected to migrate along the Pacific Ocean.We encourage ringing groups in East-Southeast Asia and Australia to use this simple method to keep adding knowledge about Black-tailed Godwits in the East Asian-Australasian Flyway.展开更多
Five hundred samples ofDonax spp. were collected from five beaches (Khao Tao, Sea Pine Garden, Pran Buri Forest Park, Sam Roi Yod, and Sam Phraya) in Prachaupkhirikhan province, Thailand. Five morphological variable...Five hundred samples ofDonax spp. were collected from five beaches (Khao Tao, Sea Pine Garden, Pran Buri Forest Park, Sam Roi Yod, and Sam Phraya) in Prachaupkhirikhan province, Thailand. Five morphological variables of each individual were measured and analyzed to reveal morphological variation. The discriminant function analysis of morphology suggested a clear separation into two groups. The individuals from Khao Tao and Sea Pine Garden were grouped together while individuals from Pran Buri Forest Park, Sam Roi Yod and Sam Phraya were classified into the same group. The classification function of discriminant function analysis suggested that 70% of Khao Tao population, 70% of Sea Pine Garden population, 67% of Pran Buri Forest Park population, 64% of Sam Roi Yod population and 34% of Sam Phraya population of Donax spp. could be correctly reassigned by morphology. The misclassification individuals of Sam Phraya population were assigned to Pran Buri Forest Park and Sam Roi Yod population with the correct assignment 38% and 27%, respectively. The results obtained in this study based on morphological variation indicated that Khao Tao and Sea Pine Garden populations ofDonax spp. should be treated as separated units from the other three populations for conservation management. However, the result should be confirmed again as genetic level.展开更多
In sexually dimorphic species characterized by exaggerated male ornamentation,behavioral isola-tion is often attributed to female preferences for conspecific male signals.Yet,in a number of sexu-ally dimorphic species...In sexually dimorphic species characterized by exaggerated male ornamentation,behavioral isola-tion is often attributed to female preferences for conspecific male signals.Yet,in a number of sexu-ally dimorphic species,male mate choice also results in behavioral isolation.In many of these cases,the female traits that mediate species boundaries are unclear.Females in sexually dimorphic species typically lack many of the elaborate traits that are present in males and that are often used for taxonomic classification of species.In a diverse and largely sexually dimorphic group of fishes called darters(Percidae:Etheostoma),male mate choice contributes to behavioral isolation be-tween a number of species;however,studies addressing which female traits males prefer are lack-ing.In this study,we identified the dominant female pattern for two sympatric species,Etheostoma zonale and Etheostoma barrenense,using pattern energy analysis,and we used discriminate func-tion analysis to identify which aspects of female patterning can reliably classify species.We then tested the role of female features in male mate choice for E.zonale,by measuring male preference for computer animations displaying the identified(species specific)conspecific features.We found that the region above the lateral line is important in mediating male mate preferences,with males spending a significantly greater proportion of time with animations exhibiting conspecific female patterning in this region than with animations exhibiting heterospecific female patterning.Our results suggest that the aspects of female phenotypes that are the target of male mate choice are different from the conspicuous male phenotypes that traditionally characterize species.展开更多
Purpose:Identification of sex of unknown people becomes important in situations of mass disaster.Previous studies have shown that morphological characteristic of frontal sinus is distinctive to particular individual a...Purpose:Identification of sex of unknown people becomes important in situations of mass disaster.Previous studies have shown that morphological characteristic of frontal sinus is distinctive to particular individual and hence,literature suggests that it can be used in establishing identification of a person.However,few researches have concluded that,its use in detennining sexual dimorphism is limited.Aim:This study aimed to evaluate frontal sinus index using cone beam computed tomography(CBCT)and differentiate sex dimorphism based on the index obtained.Materials and Methods:A retrospective cross-sectional study was undertaken using three-dimensional-CBCT scans.By simple random sampling method,150 scans were selected,out of which 74 were of male and 76 were of female within the age group of20-64 years.The frontal sinus width and the height were measured,and the ratio was taken as frontal sinus index.This index was correlated to the differentiation of sex.Data were analyzed using SPSS,and sex dimorphism was assessed using discriminant function analysis.Results:The mean height of the frontal sinus in both males and females was 30.12±7.6 mm and 30.14±7.8 mm,respectively.The mean width of frontal sinus in males(13.39±3.6 mm)was slightly more than that of females(12.06±3 mm).Conclusion:The parameter frontal sinus index measured using CBCT was found to be a contributing factor in sex determination in forensic identification within the sample population.展开更多
Despite the importance of mud crab species(genus Scylla)in both coastal aquaculture and artisanal fisheries,knowledge of the species diversity and stock structure of mud crab population for their sustainable managemen...Despite the importance of mud crab species(genus Scylla)in both coastal aquaculture and artisanal fisheries,knowledge of the species diversity and stock structure of mud crab population for their sustainable management across the coastal region of Bangladesh remains obscure.Therefore,the present study was conducted to delineate the diversity and stock structure of mud crab species based on the 24 morphometric length measurements and 27 morphometric ratios data collected from the three coastal regions(Chittagong,Cox’s Bazar and Bagerhat)of Bangladesh.Based on the taxonomic keys,majority of the species(about 82.4%)were identified as S.olivacea,while the remaining(about 17.6%)was S.serrata.In consistent to our preliminary analysis,both the univariate proportion and multivariate analysis of the collected morphometric lengths and ratios data also distinctly divided the mud crabs population into two multivariate spaces as S.serrata and S.olivacea.For the further analysis of the stock structure of these two species,data were subjected to the univariate ANOVA,multivariate ANOVA,Canonical Variate Analysis(CVA),and Principal Component Analysis(PCA)according to their collection sites.Scatter plots of CVA scores between CV1 and CV2 and PCA scores between PC1 and PC2 showed that the individuals of both species clearly made clusters into three multivariate spaces with minimum overlaps according to their collection sites.In morphometric traits Linear Discriminant Function Analysis(LDFA),the average percentage of correctly classified(PCC)into the original groups of the S.olivacea and S.serrata was 100%.For stock discrimination,the average PCC into their original groups of collection sites were 100%and 99%for the S.olivacea and S.serrata,respectively.Finally,dendrogram based on the Euclidean distances consistently separated S.olivacea and S.serrata and stock structures similar to other multivariate analyses.In conclusion,our study shows that S.olivacea is the dominant mud crab species and S.serrata is the minor one,and the stock discrimination of each species should be considered in the management and conservation policy of these species along the coastal region of Bangladesh.展开更多
Determination of sex from the tibial dimensions has been attempted before in different populations.The formulae developed to determine sex of one population are not appropriate to be applied to another.Seven standard ...Determination of sex from the tibial dimensions has been attempted before in different populations.The formulae developed to determine sex of one population are not appropriate to be applied to another.Seven standard variables including the maximum length of tibia,proximal epiphyseal breadth,distal epiphyseal breadth,minimum circumference of shaft,anteroposterior diameter at nutrient foramen,transverse diameter at the nutrient foramen(TDNF),and circumference at the nutrient foramen obtained from 81 adult tibiae(56 male and 25 female)were analyzed to investigate the sexual dimorphism in the tibial dimensions to establish sex estimating formulae from the tibia in a contemporary Sri Lankan population.Results confirmed the existence of sexual dimorphism of the tibia.Discriminant functions obtained resulted in the classification accuracies ranging from 61.9%to 80.2%.The most dimorphic single parameter in males was the TDNF providing an accuracy of 92.9%,while in females,the minimum circumference of shaft provided an accuracy of 70.4%.The best multivariate equation utilizing two tibial dimensions resulted in an accuracy of 80.2%after cross‑validation.We envisage that sex estimating formulae established in this study for a contemporary Sri Lankan population will contribute toward the biological profiling and identification of unknown skeletal remains.展开更多
基金support by the National Natural Science Foundation of China Grant No.81072313
文摘Objective The aim of this study is to estimate the prevalence of autism spectrum disorder (ASD) among 18-36 month old children in the Tianjin Municipality of China, and to identify early signs of autistic children and the predictability of each individual symptom. Methods A total of 8 000 children were screened to do a questionnaire based on CHAT modified to include more early signs of autism at the age of 28-36 months. Then the at-risk children were reexamined 1.5 years later and ASD children were identified based on DSM-IV. Early signs of autism were analyzed retrospectively by using discriminant function analysis performed among ASD children, children not followed up and children followed up but failing to meet ASD criteria. Results Three hundred and sixty seven children were screened as being at-risk to ASD, and 22 of them were identified as having ASD in the subsequent diagnosis. The prevalence of ASD was 27.5 per 10 000 in Tianjin of China with a male to female ratio of 4:1. Items addressing social interactions and communications had higher predictability than other items to distinguish autistic children from non-autistic ones. Pretend play, functional play, showing and reading parents' facial expressions distinguished autistic children from those not followed up, nevertheless those followed up but failing to meet ASD criteria were not included.Conclusion The prevalence of ASD found in our study was lower than that reported in some studies by western researchers. Autism has its specific symptoms, such as deficits in social awareness, social relatedness, and social referencing.
基金supported by the Youth Scholars Program of Beijing Normal University (No. 31601868 to CX)National Natural Science Foundation of China (No. 31301888 to DL)+1 种基金General scientific research project of Education Department of Liaoning Province (L2015196 to DL)Open Fund of Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, Beijing Normal University (K1401 to DL)
文摘Background: Individuality in vocalizations may provide an effective tool for surveying populations of the Common Cuckoo(Cuculus canorus) but there remains few data on which technique to use to identify individuality. In this research, we compared the within-and between-individual variation in cuckoo calls using two different analytical methods, and discuss the feasibility of using call individuality to count male cuckoos within a population.Methods: We recorded vocalization from 13 males, and measured 15 spectro-temporal variables for each call. The majority of these call variables(n = 12) have greater variation between individuals than within individual. We first calculated the similarity(Pearson's R) for each paired calls in order to find a threshold that could distinguish calls emitted from the same or different males, and then counted the number of males based on this distinction. Second, we used the more widely accepted technique of discriminant function analysis(DFA) to identify individual male cuckoos, and compared the correct rate of classifying individuals between the two analytical methods.Results: Similarity of paired calls from the same male was significantly higher than from different males. Under a relatively broad threshold interval, we achieved a high(>90%) correct rate to distinguish calls and an accurate estimate of male numbers. Based on banded males(n = 3), we found the similarity of paired calls from different days was lower when compared with paired calls from the same day, but this change did not obscure individual identification, as similarity values of paired calls from different days were still larger than the threshold used to distinguish calls from the same or different males. DFA also yielded a high rate(91.9%) of correct classification of individuals.Conclusions: Our study suggests that identifying individual vocalizations can form the basis of an appropriate survey method for counting male cuckoos within a population, provided the performance of different analytical techniques are compared.
基金funded by the Ministry of Science,Education and Sports,Republic of Croatia,Projects:Basic Geological Map of the Republic of Croatia,1:50,000(181-1811096-1093)the Map of Mineral and Energy Resources of the Republic of Croatia(1811811096-1104)+1 种基金Metamorphic and Magmatic Events in the Panonnian Basin Basement and Dinarides(119-1191155-1156)Evolutionary Changes of the Dinarides from Subduction to Modern Adriatic Beaches(119-1191155-1159)
文摘Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments formed in different marine(with normal and reduced salinity),brackish,and freshwater environments,depending on the development stage of the Pannonian Basin System.Carbonate minerals,clay minerals and quartz are the main constituents of all pelitic sedimentary rocks,except in those from Moslavacka Gora Mt in which carbonate minerals are not present.Feldspars,pyrite,opal-CT,and hematite are present as minor constituents in some rocks.Besides calcite,dependent on the sedimentary environment and diagenetic changes,high-magnesium calcite,aragonite,dolomite and ankerite/Cadolomite are also present.Smectite or illite-smectite is the main clay minerals in the samples.Minor constituents,present in almost all samples,are detrital illite and kaolinite.In some samples chlorite is also present in a low amount.Major elements,trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust(UCC).The contents of major and trace elements as well as SiO2/Al2O3,K2O/Al2O3,Na2O/K2O,Eu/Eu*,La/Sc,Th/Sc,La/Co Th/Co,Th/Cr,Ce/Ce* and LREE/HREE ratios,show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic(silicic),i.e.felsic rocks.
基金funded by the National Natural Science Foundation of China[31830089,31801985,32270518]。
文摘Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits in the flyway have been assigned to melanuroides.However,a larger-bodied subspecies,bohaii,has recently been discovered in the flyway.As a result,the occurrence of Black-tailed Godwits in the flyway needs to be reconsidered such that the specific distribution of each subspecies becomes known.To this end,we developed a simple discriminant function to assign individuals to subspecies based on their bill and wing length.Cross-validation with individuals known to be bohaii or melanuroides,based on molecular analysis,showed the developed function to be 97.7%accurate.When applied to measurements of godwits captured at 22 sites across 9 countries in East-Southeast Asia and Australia,we found that bohaii and melanuroides occurred at most sites and overlapped in their distribution from Kamchatka to Australia.We examined photos from all along the flyway to verify this surprising result,confirming that both subspecies co-occur in most locations.Based on these results,we hypothesise that bohaii and melanuroides from the west of their breeding ranges mostly migrate over Chinese mainland.Birds of both subspecies from the east of their ranges are expected to migrate along the Pacific Ocean.We encourage ringing groups in East-Southeast Asia and Australia to use this simple method to keep adding knowledge about Black-tailed Godwits in the East Asian-Australasian Flyway.
文摘Five hundred samples ofDonax spp. were collected from five beaches (Khao Tao, Sea Pine Garden, Pran Buri Forest Park, Sam Roi Yod, and Sam Phraya) in Prachaupkhirikhan province, Thailand. Five morphological variables of each individual were measured and analyzed to reveal morphological variation. The discriminant function analysis of morphology suggested a clear separation into two groups. The individuals from Khao Tao and Sea Pine Garden were grouped together while individuals from Pran Buri Forest Park, Sam Roi Yod and Sam Phraya were classified into the same group. The classification function of discriminant function analysis suggested that 70% of Khao Tao population, 70% of Sea Pine Garden population, 67% of Pran Buri Forest Park population, 64% of Sam Roi Yod population and 34% of Sam Phraya population of Donax spp. could be correctly reassigned by morphology. The misclassification individuals of Sam Phraya population were assigned to Pran Buri Forest Park and Sam Roi Yod population with the correct assignment 38% and 27%, respectively. The results obtained in this study based on morphological variation indicated that Khao Tao and Sea Pine Garden populations ofDonax spp. should be treated as separated units from the other three populations for conservation management. However, the result should be confirmed again as genetic level.
基金This research was funded in part by an Animal Behavior Society Student Research Grant provided to NSR.
文摘In sexually dimorphic species characterized by exaggerated male ornamentation,behavioral isola-tion is often attributed to female preferences for conspecific male signals.Yet,in a number of sexu-ally dimorphic species,male mate choice also results in behavioral isolation.In many of these cases,the female traits that mediate species boundaries are unclear.Females in sexually dimorphic species typically lack many of the elaborate traits that are present in males and that are often used for taxonomic classification of species.In a diverse and largely sexually dimorphic group of fishes called darters(Percidae:Etheostoma),male mate choice contributes to behavioral isolation be-tween a number of species;however,studies addressing which female traits males prefer are lack-ing.In this study,we identified the dominant female pattern for two sympatric species,Etheostoma zonale and Etheostoma barrenense,using pattern energy analysis,and we used discriminate func-tion analysis to identify which aspects of female patterning can reliably classify species.We then tested the role of female features in male mate choice for E.zonale,by measuring male preference for computer animations displaying the identified(species specific)conspecific features.We found that the region above the lateral line is important in mediating male mate preferences,with males spending a significantly greater proportion of time with animations exhibiting conspecific female patterning in this region than with animations exhibiting heterospecific female patterning.Our results suggest that the aspects of female phenotypes that are the target of male mate choice are different from the conspicuous male phenotypes that traditionally characterize species.
文摘Purpose:Identification of sex of unknown people becomes important in situations of mass disaster.Previous studies have shown that morphological characteristic of frontal sinus is distinctive to particular individual and hence,literature suggests that it can be used in establishing identification of a person.However,few researches have concluded that,its use in detennining sexual dimorphism is limited.Aim:This study aimed to evaluate frontal sinus index using cone beam computed tomography(CBCT)and differentiate sex dimorphism based on the index obtained.Materials and Methods:A retrospective cross-sectional study was undertaken using three-dimensional-CBCT scans.By simple random sampling method,150 scans were selected,out of which 74 were of male and 76 were of female within the age group of20-64 years.The frontal sinus width and the height were measured,and the ratio was taken as frontal sinus index.This index was correlated to the differentiation of sex.Data were analyzed using SPSS,and sex dimorphism was assessed using discriminant function analysis.Results:The mean height of the frontal sinus in both males and females was 30.12±7.6 mm and 30.14±7.8 mm,respectively.The mean width of frontal sinus in males(13.39±3.6 mm)was slightly more than that of females(12.06±3 mm).Conclusion:The parameter frontal sinus index measured using CBCT was found to be a contributing factor in sex determination in forensic identification within the sample population.
基金This study was funded by the Chittagong Veterinary and Animal Sciences University(CVASU)research budget and University Grants Commission(UGC)of Bangladesh.Supports from the masters’students and supporting staffs of the Department of Marine Bioresource Science(MBS)of CVASU are gratefully appreciated.
文摘Despite the importance of mud crab species(genus Scylla)in both coastal aquaculture and artisanal fisheries,knowledge of the species diversity and stock structure of mud crab population for their sustainable management across the coastal region of Bangladesh remains obscure.Therefore,the present study was conducted to delineate the diversity and stock structure of mud crab species based on the 24 morphometric length measurements and 27 morphometric ratios data collected from the three coastal regions(Chittagong,Cox’s Bazar and Bagerhat)of Bangladesh.Based on the taxonomic keys,majority of the species(about 82.4%)were identified as S.olivacea,while the remaining(about 17.6%)was S.serrata.In consistent to our preliminary analysis,both the univariate proportion and multivariate analysis of the collected morphometric lengths and ratios data also distinctly divided the mud crabs population into two multivariate spaces as S.serrata and S.olivacea.For the further analysis of the stock structure of these two species,data were subjected to the univariate ANOVA,multivariate ANOVA,Canonical Variate Analysis(CVA),and Principal Component Analysis(PCA)according to their collection sites.Scatter plots of CVA scores between CV1 and CV2 and PCA scores between PC1 and PC2 showed that the individuals of both species clearly made clusters into three multivariate spaces with minimum overlaps according to their collection sites.In morphometric traits Linear Discriminant Function Analysis(LDFA),the average percentage of correctly classified(PCC)into the original groups of the S.olivacea and S.serrata was 100%.For stock discrimination,the average PCC into their original groups of collection sites were 100%and 99%for the S.olivacea and S.serrata,respectively.Finally,dendrogram based on the Euclidean distances consistently separated S.olivacea and S.serrata and stock structures similar to other multivariate analyses.In conclusion,our study shows that S.olivacea is the dominant mud crab species and S.serrata is the minor one,and the stock discrimination of each species should be considered in the management and conservation policy of these species along the coastal region of Bangladesh.
文摘Determination of sex from the tibial dimensions has been attempted before in different populations.The formulae developed to determine sex of one population are not appropriate to be applied to another.Seven standard variables including the maximum length of tibia,proximal epiphyseal breadth,distal epiphyseal breadth,minimum circumference of shaft,anteroposterior diameter at nutrient foramen,transverse diameter at the nutrient foramen(TDNF),and circumference at the nutrient foramen obtained from 81 adult tibiae(56 male and 25 female)were analyzed to investigate the sexual dimorphism in the tibial dimensions to establish sex estimating formulae from the tibia in a contemporary Sri Lankan population.Results confirmed the existence of sexual dimorphism of the tibia.Discriminant functions obtained resulted in the classification accuracies ranging from 61.9%to 80.2%.The most dimorphic single parameter in males was the TDNF providing an accuracy of 92.9%,while in females,the minimum circumference of shaft provided an accuracy of 70.4%.The best multivariate equation utilizing two tibial dimensions resulted in an accuracy of 80.2%after cross‑validation.We envisage that sex estimating formulae established in this study for a contemporary Sri Lankan population will contribute toward the biological profiling and identification of unknown skeletal remains.