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1.
In a sample from Northeast Bulgaria (500 males, 500 females) fluctuating and directional asymmetries of the radial and ulnar finger ridge-counts were studied, each sex separately and finger-by-finger. Neither the ridge counts nor their fluctuating asymmetries show any considerable sex difference. In contrast, the curves of the ulnar and radial directional asymmetries, each of them being similarly distributed over the digits in both sexes, are contrasted in males and females. One interpretation is that the sex chromosomes exert a considerable effect upon the mediolateral developmental gradients and so cause a set of well expressed sex differences in the directional asymmetries of the ulnar and radial finger ridge-counts.  相似文献   

2.
In this study, we analysed inter-sex differences within two linguistic groups from the Sardinian linguistic area and intra-sex differences between the two groups by means of 41 quantitative digital dermatoglyphic variables: 20 digital dermatoglyphic traits (radial and ulnar ridge counts on each of the 10 fingers), 15 digital dermatoglyphic directional asymmetry variables, total finger ridge count, bilateral summed radial and ulnar finger ridge counts, an index of asymmetry between homologous fingers, and two indices of intra-individual diversity of finger ridge counts. The comparisons between males and females within the same linguistic groups and between the males of the two groups and the females of the two groups were carried out with the Mann-Whitney test at a prefixed level of alpha = 0.05, using the Bonferroni correction for multiple comparisons. The results indicate a strong similarity of the two linguistic groups in the inter-sex differences, whereas there are no significant differences between them for either males or females. The similar pattern of sexual dimorphism and the homogeneity of the males and females of the two groups suggest a common genetic matrix of these Sardinian-speaking groups.  相似文献   

3.
为了解太行山猕猴掌面花纹嵴数的方向性不对称和波动性不对称的特征和性差,对26例(雌18例,雄8例)肤纹完整清晰的太行山猕猴的掌面花纹嵴数进行计数,用SPSS 13.0统计软件进行T-检验和相关分析.结果表明:在方向性小对称有关变量中存在性别差异,变量之间存在弱的负相关,波动性不对称量不存在性差,变量之间的相关系数有不同程度的性差.  相似文献   

4.
The evaluation of dermatoglyphic asymmetry represents a specific estimate of the stability of intrauterine development. In the present study, we analyzed the level of asymmetry and diversity in the radial and ulnar counts of each finger in 400 health Sardinian individuals and in 469 Sardinian subjects with four common diseases in Sardinia: type 1 diabetes, type 2 diabetes, arterial hypertension and multiple sclerosis. To measure the asymmetry, we used three indices: fluctuating asymmetry, the index of asymmetry and the index of diversity. The differences from the control group are only rarely significant. The values of fluctuating asymmetry do not present a particular distribution in relation to the pathologies, while the values of {ie139-1} and diversity are usually higher in the pathological groups. The differentiation is especially evident in the subjects with multiple sclerosis, intermediate in the diabetics and practically nil in the hypertense individuals.  相似文献   

5.
The data used in this study are the fingerprints of 744 females from 6 Sardinian linguistic groups. We analyzed 15 dermatoglyphic variables of directional asymmetry, namely the right vs left signed differences between i-th homologous fingers for larger ridge counts, radial counts and ulnar counts. Principal components analysis of the dermatoglyphic variables in the females of Sardinian linguistic groups revealed a pattern of biological relations among the groups which is consistent with their linguistic, but especially historical and demographic, backgrounds.  相似文献   

6.
Relationships between measures of body size, asymmetry, courtship effort, and mating success were investigated in the housefly, Musca domestica (Diptera: Muscidae). A previous study indicated that both male and female flies with low fluctuating asymmetry enjoyed enhanced mating success. The aim of our investigations was to determine whether the greater success of symmetrical males is due to variation in male mating effort or to female choice and whether males exhibited mate choice. However, our study found directional rather than fluctuating asymmetry with both male and female flies having, on average, longer left wings than right. Also, asymmetry was not related to mating success in either sex. Rather, both males and females appeared to exhibit choice on the basis of the size of potential mates, with males preferring females with long bodies and females preferring heavy males. Possible benefits from choice of large mates are discussed. The initial mating strikes (in which the male leaps onto the back of the female) did not appear to be targeted according to female morphology, and their frequency did not vary according to male morphology. This indicates that mate choice by both sexes according to size probably occurs during the later stages of courtship, when the flies are in intimate contact. Possible reasons for the absence of choice according to asymmetry are discussed.  相似文献   

7.
An analysis of fluctuating asymmetry was conducted on populations of the blacklegged tick Ixodes scapularis. The eight groups used in this study consisted of larvae and nymphs and males and females from the states of Minnesota, Massachusetts, Maryland, Missouri, North Carolina and Georgia and the F1 progenies of reciprocal crosses between ticks from Massachusetts and Georgia. Measurements included 16 larval, 19 nymphal, ten female and 12 male bilateral characters. Only five differences between the right and left bilateral characters had normal distributions with means of zero and differences in variances between the groups. These five characters included three setal lengths of the larvae, the spiracular plate length of females and the coxa I internal spur widths of males. Bivariate plots of character size ((R+L)/2) and asymmetry (R-L) showed no correlation. In the spiracular plate lengths of females and one of the setal lengths, ticks from Massachusetts had significantly less within-group variance than all the other groups. The only character in which fluctuating asymmetry was observed was the coxa I internal spur width of males, in which ticks from Minnesota, Missouri and North Carolina had significantly greater variance than the remaining groups; fluctuating asymmetry in this character may be explained by sexual selection. The cross progeny did not demonstrate any fluctuating asymmetry, as would be expected if the northern and southern forms of I. scapularis were true species. The virtual lack of fluctuating asymmetry in the characters used in this study further supports the conclusions of other studies which concluded that I. scapularis is a species with clinal variation and a broad geographic distribution.  相似文献   

8.
We present a new measure of morphological asymmetry that avoids most of the statistical problems inherent in character-by-character analysis of size or shape. The method is an application of Procrustes analysis, which computes best-fitting super-positions of configurations of landmarks to the left and right sides of a single specimen. The Procrustes method combines subtle deviations in all aspects of the landmark configuration into one net asymmetry score. Directional asymmetry is separated from fluctuating asymmetry in a simple partition of a net sum-of-squares, and geometrical details of either component can be inspected by traditional methods of multivariate statistical analysis of landmarks. We demonstrate this method in a comparison of wing venation asymmetry in male (haploid) and female (diploid) honey bees (Apis mellifera). In addition we investigate the effects of ploidy and inter-subspecies hybridization on asymmetry and wing venation abnormalities, using the subspecies A. m. mellifera, A. m. carnica, and the hybrid strain “Nigra”. Results suggest that while the haploid males showed a higher frequency of wing venation abnormalities and greater total asymmetry than the diploid females, most of the asymmetry difference between males and females was in the form of directional, not fluctuating, asymmetry. Hybrid females had a higher frequency of wing venation abnormalities than females of either subspecies, but there were no significant differences in the mean level of asymmetry among females of A. m. mellifera, A. m. carnica and hybrid Nigra. Hybrid males had higher absolute frequency of wing venation abnormalities and asymmetry than males of either subspecies. However the mean frequency of venation abnormalities did not differ significantly between Nigra and A. m. carnica males, and mean asymmetries were not significantly different between Nigra and A. m. mellifera males. We discuss the relationship which is assumed to exist between developmental stability and fluctuating asymmetry in light of our result.  相似文献   

9.
Abstract 1. The form of asymmetry in bilateral organs usually follows the same pattern within single populations. However, some exceptions may occur when a population consists of different phenotypes that are from different ontogenic backgrounds and under different selective pressures. We investigated the asymmetric patterns of mandibles of larvae, females, and males in the stag beetle Prosopocoilus inclinatus. 2. Larval mandibles exhibited directional asymmetry both in length and cross direction, whereas female mandibles showed directional asymmetry in cross direction. These asymmetric structures might be more effective in cutting wood fibres. 3. For the relation of male mandible length to body size, a model with a switch point showed a better fit to the data than a convex curve model. This shows that the males are dimorphic with two distinct morphs. 4. The form of asymmetry in male mandible length differed between the morphs. The smaller males exhibited left‐biased directional asymmetry in common with larvae, whereas the larger males exhibited fluctuating asymmetry. 5. This is a novel finding of a morph‐dependent asymmetry. The morph‐dependent asymmetry in males may be as a result of different selection on each morph or a developmental constraint from larval mandibles to adult ones.  相似文献   

10.
Radial and ulnar ridge counts on each of the 10 fingers, total finger ridge count, bilateral summed radial and ulnar finger ridge counts, an index of asymmetry between homologous fingers and two indices of intraindividual diversity of finger ridge counts were used to identify biological relationships among Sardinian linguistic groups. Stepwise discriminant analysis of 26 digital traits of 1258 Sardinians, 647 females and 611 males, was carried out. The results indicate high intergroup heterogeneity; moreover, with p≤0.01 as F-to-enter and p≤0.05 as F-to-remove, only 5 of the 26 digital variables are in the model (URC R5, RRC L5, RRC R5, URC R4, URC L5). The pattern of interpopulation biological relationships shows a clearly distinct position of the Gallurian group (both males and females), which speaks an Italian dialect. It originated mainly from Corsican immigration to the Gallura region starting from the XVII century. While the properly Sardinian linguistic groups (Campidanian and Logudorian) and the Sassarian group, which speaks an Italian dialect that developed as a “lingua franca” during the Middle Ages (XII–XIV centuries) due to linguistic contact between Sardinians and Italians, are positioned close to one another. This pattern agrees more with the ethno-historical back-ground than with the linguistic one.  相似文献   

11.
The present study is carried out to evaluate the effect of chromosomal morbidity (82% are 47XXY and in the remaining cases there is the extra X and/or Y) in the males with Klinefelter’s syndrome, based on dermatoglyphic traits and indices of diversity and asymmetry. The main objectives of the present study is to find dermatoglyphic traits and fluctuating asymmetry indices which could be “marker traits” and could indicate the degree of developmental instability of the organism. The sample of males with Klinefelter’s syndrome (N=171) was collected in the Institute of Human Genetics of Sheba Medical Center, Ramat-Gan, Israel, by Professor Bat-Miriam Katznelson during 20 years, between 1968–1988. All patients were confirmed by chromosomal examination. The finger and palm prints were collected with the aid of pads manufactured by Lamedco Inc., Knoxville, Tennessee, U.S.A. Interpretation of the prints was according to Cummins and Midlo (1961) and Penrose (1968) and included identification of patterns, ridge counts and the measurements of distances sum of and angles in the palms. 79 dermatoglyphic variables for every patient: 28 continuous traits, 9 discrete traits, 11 indices of intra-individual diversity, 15 indices of directional asymmetry and 16 indices of fluctuating asymmetry were estimated. The problem of asymmetry, fluctuating and directional and of intraindividual diversity of quantitative dermatoglyphic traits is reviewed here as well as illustrated by data obtained on a sample of healthy control group of Jews from Israel. In this first part of our paper we will discuss the data on individual dermatoglyphic traits on digits and palms. The second part will be dedicated to multivariate analysis in order to compare between Klinefelter’s syndrome and control healthy individuals based on quantitative dermatoglyphic traits and indices of diversity and asymmetry.  相似文献   

12.
It is assumed that the transition from the Late Eneolithic to the Early Bronze Age in Central Europe was associated with substantial changes in subsistence and the perception of gender differences. However, the archeological record itself does not entirely support this model. Alternatively, this transition may be interpreted as a continuous process. We used asymmetry in external dimensions, and asymmetry in size and distribution of cortical tissue of humeri to elucidate the nature of this transition with respect to differences in manipulative behavior. The total sample of 67 individuals representing five archaeological cultures was used. The results indicate that the pattern of asymmetry of the humeral external measurements and the cross-sectional parameters taken at 35% of humeral biomechanical length remain stable during the Late Eneolithic and Early Bronze Age. However, females of both periods show fluctuating asymmetry for all of the cross-sectional parameters, but directional asymmetry for biomechanical length. Males are nonsignificantly shifted from the line of equivalence for biomechanical length, but exhibit directional asymmetry for the cortical area and polar moment of area. Only distal articular breadth yields fluctuating asymmetry for both females and males in both periods. Thus, the transition from the Late Eneolithic to the Early Bronze Age can be seen as a continuous process that probably affected only a limited part of human activities. We interpret the differences between females and males of both periods as evidence of gender-specific activities; males might have been associated with extra-domestic agricultural labor that resulted in asymmetrical manipulative loading and females with domestic labor with symmetrical manipulative loading in both periods.  相似文献   

13.
Finger dermatoglyphics of the Tibetans   总被引:1,自引:0,他引:1  
Finger prints of 156 Tibetan males and 150 females have been analyzed. Whorls are more abundant in Tibetan males (60.24%) than in females (48.67%). The index of pattern intensity shows a higher value in males (15.95) than the females (14.65). The bimanual differences (both in males and females) are not statistically significant for the occurrence of pattern on the digits of the right and left hands. However, the difference between the sexes for the occurrence of patterns on the finger balls, are statistically significant. Ridge counting was done for each finger. On all fingers, Tibetan males have higher ridge-counts than females. The possible tendency for the right hands to possess higher ridge-counts cannot be demonstrated statistically. Tibetans show greater affinity with the Southern Mongoloids in the frequency distributions of pattern types on the finger balls. However, a more detailed dermatoglyphic study of all the Mongoloid populations in South East Asia, Central Asia and Far East would yield information of great value in disclosing the palmar pattern distributions among the Mongoloids.  相似文献   

14.
We analysed asymmetry in the wings of the speckled wood butterfly (Pararge aegeria)by measuring area, length and width of fore- and hindwings. The type of asymmetry is fluctuating except for fore- and hindwing area, and forewing width in males, where asymmetry is directional. The amount of asymmetry (variance of the left wing minus the right wing) is less in males than in females. Within males asymmetry was directional and less in pale, predominantly territorial males than in melanic, predominantly non-territorial males. Asymmetry was negatively related to growth rate within females, but not within males. Females grew faster than males, but had higher asymmetry, whereas the more asymmetrical melanic males grew more slowly than pale males. The differences in the type and amount of asymmetry between the sexes and colour classes suggest a relationship with sex-specific flight patterns such as the territorial spiralling flight of males. We hypothesize that slightly asymmetrical males turn faster, and therefore are superior in territorial disputes over more symmetrical or extremely asymmetrical males. This implies that sexual selection via male–male competition influences the type and amount of asymmetry. The existence of more extremely asymmetrical individuals in females, and to a lesser extent in non-territorial males, may indicate that there are costs in reducing asymmetry.  相似文献   

15.
采用体质测量法以天津汉族正常者310例(女性231例, 男性79例)为对照, 分析天津汉族抑郁症患者202例(女性140例, 男性62例)的皮纹特征。经统计学分析, 结果显示: 抑郁症患者组双手a-b嵴线数、小鱼际及各指间区真实花纹出现率较正常组无显著性差异; 指端斗形纹出现率增加(P<0.01); 掌部a-b嵴线数波动不对称性(FA值)增加(P<0.01)、atd角偏大(P<0.01)、桥贯型及皱褶掌出现率增加(P<0.01)等可能是抑郁症患者的主要皮纹特征。  相似文献   

16.
We tested whether directional selection on an index-based wing character in Drosophila melanogaster affected developmental stability and patterns of directional asymmetry. We selected for both an increase (up selection) and a decrease (down selection) of the index value on the left wing and compared patterns of fluctuating and directional asymmetry in the selection index and other wing traits across selection lines. Changes in fluctuating asymmetry across selection lines were predominantly small, but we observed a tendency for fluctuating asymmetry to decrease in the up-selected lines in both replicates. Because changes in fluctuating asymmetry depended on the direction of selection, and were not related to changes in trait size, these results fail to support existing hypotheses linking directional selection and developmental stability. Selection also produced a pattern of directional asymmetry that was similar in all selected lines whatever the direction of selection. This result may be interpreted as a release of genetic variance in directional asymmetry under selection.  相似文献   

17.
Fluctuating asymmetry was measured by the Pearson correlation coefficient between a-b ridge-counts of the right and left hands. Such data were available for 38 samples, which were grouped by major geographical regions. Significant heterogeneity exists within some of the geographical groups but the between geographical group component is highly significant in both sexes. Our results show that a sizable fraction of variation in fluctuating asymmetry is related to geographical race. There is no evidence that it follows environmental or ecological lines. The variation between geographical races suggests that there is a genetic component in the magnitude of fluctuating asymmetry.  相似文献   

18.
Developmental stability reflects the ability of a genotype to develop in the same way under varying environmental conditions. Deviations from developmental stability, arising from disruptive effects of environmental and genetic stresses, can be measured in terms of fluctuating asymmetry, a particularly sensitive indicator of the ability to cope with these stresses during ontogeny. In an inbred Adriatic island population, we expected dental arch fluctuating asymmetry 1) to be higher than in an outbred sample from the same island, and 2) within this population, to increase with the level of inbreeding. Due to environmental stress, we also expected to find higher fluctuating asymmetry in the outbred island population than in an urban reference group from the same country. The material consisted of 506 dental casts of 253 children from 1) the island of Hvar, and 2) Zagreb, Croatia. Three-dimensional coordinates of 26 landmarks spanning the arches were digitized. The analysis partitioned the asymmetry of arch forms into components for directional and fluctuating bilateral asymmetry, using the appropriate Procrustes method (geometric morphometrics). The results corroborated the hypotheses. Fluctuating asymmetry was found to be higher on the island than in Zagreb in all groups and in both jaws, and increased significantly with endogamy level in the lower jaw. There was no significant directional asymmetry in the Zagreb sample and likewise none in the upper jaws of the outbred island group, but significant directional asymmetry in both jaws of the inbred population and also in the lower jaws of the outbred island group. These results suggest an environmental as well as a genetic influence on dental arch asymmetry. Although the lower jaws expressed these two stresses almost additively, the upper jaws appeared to be better buffered. The role of directional asymmetry as a potential indicator of craniofacial developmental instability clearly merits further attention.  相似文献   

19.
Stabilizing selection for a set of morphometric wing traits was combined with directional selection for increased expression of radius incompletus (ri) mutation of Drosophila melanogaster. Three experimental regimens were used: directional and stabilizing selection (stabilized lines); directional selection (unstabilized lines); no selection (control lines). The dynamics of two fitness-associated parameters (coefficient of fluctuating asymmetry and population size) was registered during the experiment. At the end of experiment, selection competitive ability test was carried out. The competitive indices did not significantly differ under various treatments, while fluctuating asymmetry was significantly lower in stabilized than in unstabilized lines. Average population size was greater in stabilized lines as compared to the unstabilized ones. The possible causes for these differences are discussed.  相似文献   

20.
The socioeconomic structure of an early medieval society from the Mikul?ice settlement (Czech Republic) was studied on the basis of an evaluation of the fluctuating and directional asymmetry (DA) of skulls. Two distinct inhabited regions, castle and sub‐castle, were compared. Fluctuating asymmetry (FA) was used as a bioindicator of environmental stress, which is thought to have been different in the Mikul?ice castle and sub‐castle regions. DA is consistent with biomechanical loading, and it was expected to reflect different subsistence patterns. The material consisted of 129 crania from what was presumed to be a higher socioeconomic class (Mikul?ice castle) and 71 crania from middle and lower socioeconomic classes (Mikul?ice sub‐castle). As a comparative sample, 138 crania from modern, lower socioeconomic classes (Pachner Collection) were used. The three‐dimensional coordinates of 68 landmarks were digitized and analyzed using geometric morphometrics. In terms of DA, the highest values were recorded in the sub‐castle sample and confirmed their lower socioeconomic position, with a grittier and lower protein diet compared with the castle sample. In terms of FA, distinctive differences between the sexes were found. In males, no differences were observed between castle and sub‐castle, and the lowest FA values were recorded. In females, significantly higher values of FA were found, surprisingly in the castle sample, comparable with the more stressed Pachner Collection. We suspect that the FA reflects a more varied population of castle females as a consequence of patrilocality, although environmental stress remains a possibility. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

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