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1.
Data from the 1800 US census were used to study relationships by isonymy among 7 civil subdivisions of Bedford County, Pennsylvania. Two analyses of the data were conducted. In the first analysis heads of household served as the unit of analysis. In the second analysis the total number of individuals in each household was used to correct for varying family sizes. All measures of internal differentiation were approximately doubled when the complete population numbers were used. The head-of-household analysis produced FST and RST values of 0.0012 and 0.0007, respectively; the complete population analysis yielded 0.0021 for FST and 0.0015 for RST. Interpopulation a priori kinship estimations were similar using both methods. Conditional kinship estimations varied more, with almost all values negative, but the head-of-household estimates were less negative. Multidimensional scaling of isonymy values coincided fairly well with actual geographic relationships, but a Mantel test revealed no significant relationship between geographic distances and isonymy, and isolation by distance values indicated a low relationship between the 2 measures. The population of the county was heterogeneous, with low kinship between its constituent communities. This appears to be a result of kin-structured long-distance migration rather than of local processes. The head-of-household values are more comparable with other studies and more representative of population relationships; complete population values exaggerate heterogeneity because of random fluctuations in household size.  相似文献   

2.
The isonymy structure of the Netherlands was studied using the surname distribution of 2.4 million private telephone users selected from a 1996 commercial CD-ROM containing the names of 6.3 million users in the country. The users were distributed in 226 towns selected on a geographic basis to form an approximately regular grid throughout the Netherlands. Names of telephone users in each town were downloaded from the CD-ROM, with private users being selected for inclusion in the analysis. The shortest linear distance between several nearest neighboring towns was less than 2 km (e.g., Kampen and Ijsselmuiden, Krommen and Zaandijk, Hendrikdo and Papendrecht) and the longest distance was 326 km (Delfzijl and Oostburg ZL). The number of different surnames revealed by the analysis was 126,485. Lasker's distance, the negative value of the logarithm of isonymy between localities, was found to be significantly correlated with linear geographic distance, with r = 0.47 +/- 0.006. A dendrogram built using the matrix of isonymy distances, using the nearest neighbor-joining method, separates the Dutch towns into several clusters, most of them correlated with traditional Dutch regions. Comparisons with the results of previous analyses of the structure of other European countries are given. From the present analysis, isolation by distance emerges clearly, and it is relevant, although much weaker than in Switzerland, Austria, Italy, and Germany. The random component of inbreeding estimated from isonymy indicates a considerable degree of homogeneity in the Netherlands.  相似文献   

3.
Analysis of the inbreeding coefficient, its structure and dynamics in rural and urbanized populations of the Kostroma province was performed. The coefficient of inbreeding was estimated for the "old" and "new" villages via migration and isonymy, the values being 0.001185; 0.000786 and 0.001341; 0.000682, respectively. It follows from these data that there is a good agreement between the values of the inbreeding coefficient estimated by two different methods and that this coefficient is diminished doubly in "new" villages. The coefficient of inbreeding in small towns was estimated via isonymy. It is 0.000704 in ancient and 0,000229 in modern towns. The decrease in the inbreeding coefficient was more pronounced in towns, as compared to villages.  相似文献   

4.
The isonymy structure of the 48 states of the continental United States of America was studied using the surname distributions of 18 million telephone users, distributed in 247 towns. The shortest linear distance between nearest neighbor towns included in the sample was 12.0 km. The largest distance was 4,577 km. The number of different surnames found in the whole analysis was 899,585. Lasker's distance was found to be significantly but weakly correlated with the geographic distance, with r = 0.21 +/- 0.01. A dendrogram of the 48 states was built from the matrix of isonymy distances: it divides the US into several clusters, in general correlated with geography. A notable exception is California and New Jersey, which cluster together. Wisconsin is separated from all other states. An important cluster is formed by Texas, Colorado, New Mexico, Nevada, and Arizona, together with Illinois and Florida. It was observed that Hispanic surnames are among the most frequent in Illinois, as they are in New Jersey and California. No main distinction among the states clearly attributable to surnames of French origin was detected; however, New Hampshire, Vermont, and Maine which have a considerable number of these surnames belong to the same northeastern cluster. From the present analysis, the great mobility of the US population emerges clearly, and it seems relevant that the practical absence of isolation by distance is seen also considering only small towns. It appears that groups of different origin are well-mixed over the whole area of the United States. The values of isonymy indicate that the south-central area of the USA has the highest level of inbreeding. In fact, the heterogeneity in surname composition is greater in the coastal areas, particularly on the East Coast, than anywhere else in the USA.  相似文献   

5.
The method of isonymy to estimate inbreeding is applied to the historical population of the Quebrada de Humahuaca (Province de Jujuy, Republic of Argentina). Data from the baptismal records of the Parochial Church of Humahuaca from 1734 to 1810 were grouped into two periods, 1734-72 and 1773-1810. The analysis was carried out twice: (a) using the surnames exactly as they were registered; (b) combining homonymous surnames which were pronounced or spelt in a similar way. The random and non-random components of inbreeding have been investigated through different methods. There were no significant differences between the results of the two analyses, nor between the expected and observed isonymy. The value of F lies somewhere between those for offspring of first cousins once removed and second cousins once removed. There is a tendency for F and its components to increase through time. It is concluded that the high altitude aboriginal population of Humahuaca Parish must have behaved as a panmictic unit.  相似文献   

6.
FST was estimated for 67 communities and 6 small towns of Kostroma province. The mean FST value for rural and urban populations was (0.83 +/- 0.08).10(-3) and (0.29 +/- 0.07).10(-3), respectively. The connection between FST values and the load of autosomal-recessive disorders was established; the coefficient of correlation (by Chuprov) was 0.34 (chi 2 = 8.45; P less than 0.05). The matrices of genetic distances for two groups of districts of Kostroma province, based on surnames frequencies, were calculated. Dendrogramms were constructed using genetic distances, which reflect the degree of genetical similarity of the populations. The conclusion drawn from the analysis of these dendrogramms is that there is distinct isolation by distance in populations of Kostroma province. It is shown that genetical subdivision of populations is dependent on geographical and some other factors and on the load of autosomal-recessive pathology in the population.  相似文献   

7.
To study the isonymy structure of Texas, we analyzed the surname distributions of 3.6 million telephone users registered for the year 1996 in 232 towns distributed in the 7 regions of the state. The number of different surnames was 235,740. Matrices of isonymy distances between towns and between geographic regions were constructed and tested for correlation with geographic distance. We found that isonymy distances between the seven regions showed borderline or no correlation with geographic distance, with r = 0.089 +/- 0.232, r = 0.492 +/- 0.232, and r = 0.337 +/- 0.232 for Lasker's, Euclidean, and Nei's distances, respectively. Isonymy distances between towns were significantly correlated with geographic distance, with r = 0.249 +/- 0.006 for Lasker's distance, r = 0.338 +/- 0.006 for the Euclidean distance, and r = 0.418 +/- 0.006 for Nei's distance. Two dendrograms, one for the 7 regions and one for the 232 towns, were built from the matrices of Nei's distances. The dendrogram for regions indicates that a main surname differentiation exists between the East and West areas of Texas, with West Texas being predominantly Hispanic and East Texas being predominantly English-speaking. The dendrogram for the towns confirms in detail the differences identified by the matrix of distances between regions. Random inbreeding calculated from isonymy, F(ST), was highest in the west and in the south of the state. It was lowest in the area of Austin and Houston. Average Fisher's alpha for towns was 734, for regions it was 1,047, and for Texas as a whole it was 1,230. The geographic distribution of alpha in the state shows distinctly lower values in the traditionally Hispanic west and higher values in the east and on the Gulf of Mexico.  相似文献   

8.
The isonymy structure of Italy was studied using the surname distribution of 5,043,580 private telephone users selected from a 1996 commercial CD-ROM that contains all 24 million users in the country. The users were distributed in 123 towns selected on a geographic basis. The 123 towns were either on the main communication roads of the country or at the ends of such roads. The shortest distance between nearest neighbor towns was 5.3 km (Carrara and Massa), and the largest distance was 1,136 km (Aosta and Castrignano del Capo). The number of different surnames found in the whole analysis was 215,623. Lasker's distance, the negative value of the logarithm of random isonymy between localities, was linearly and significantly correlated with the logarithm of geographic distance, with r = 0.63 +/- 0.008. A dendrogram was built from the matrix of isonymy distances, using UPGMA. It separates the Italian towns into 5 main clusters: 1 in the southern portion of the country, a second cluster toward the center, and 3 in the northern area of Italy. Within each cluster small subclusters with specific geographic distributions could be related to regional borders. Comparisons with the results of a previous analysis of Switzerland and Germany's structures are given. From the present analysis isolation by distance emerges clearly, although it is less strong than in Switzerland and stronger than in Germany. The random component of inbreeding estimated from isonymy indicates that the southern area of Italy is on average more inbred than the northern area. In fact, the heterogeneity is greater in the northern area, particularly in the plain of the Po River, than anywhere else in Italy.  相似文献   

9.
We compare the performance of Nm estimates based on FST and RST obtained from microsatellite data using simulations of the stepwise mutation model with range constraints in allele size classes. The results of the simulations suggest that the use of microsatellite loci can lead to serious overestimations of Nm, particularly when population sizes are large (N > 5000) and range constraints are high (K < 20). The simulations also indicate that, when population sizes are small (N /= 50) and many loci (nl >/= 20), RST performs better than FST for most of the parameter space. However, FST-based estimates are always better than RST when sample sizes are moderate or small (ns 相似文献   

10.
Empirical measures of fire-service quality and efficiency are examined for New York City in the period 1968–1979. Marked decreases in the ability to control and contain structural fires are found to result from a program of fire-service reductions begun in 1972. Exacerbated by the New York City fiscal crisis of 1975, decreases in fire-service efficiency since 1972 appear to have initiated a geographically spreading and apparently recurrent fire epidemic. The decreases have accelerated since 1976, implying that recurring epidemic episodes could be more severe than the 1974–1977 crisis, which destroyed large areas in some neighborhoods of the city, including the South Bronx, Bushwick, Brownsville, East New York, East Harlem, and others. The results of an extensive data analysis are contrasted with the methods and conclusions of a widely circulated study entitled Setting Municipal Priorities 1981.  相似文献   

11.
Several authors have argued that three separate introductions of roughly 100 individuals were required initially to establish the House Sparrow (Passer domesticus) in the Brooklyn, New York area. We argue that these claims are in error and that the actual record suggests that it is likely the initial introduction of just 16 birds in 1851 was all that was required to establish the species in New York. We further suggest that a similar level of scrutiny of historical records will reveal more examples of misinterpretations and errors, casting doubt on the validity of studies that claim propagule pressure has played an important role in determining the fate of bird introductions.  相似文献   

12.
I use the concept of “engaged anthropology” to frame a discussion of how “spatializing culture” uncovers systems of exclusion that are hidden or naturalized and thus rendered invisible to other methodological approaches. “Claiming Space for an Engaged Anthropology” is doubly meant: to claim more intellectual and professional space for engagement and to propose that anthropology include the dimension of space as a theoretical construct. I draw on three fieldwork examples to illustrate the value of the approach: (1) a Spanish American plaza, reclaimed from a Eurocentric past, for indigenous groups and contemporary cultural interpretation; (2) Moore Street Market, an enclosed Latino food market in Brooklyn, New York, reclaimed for a translocal set of social relations rather than a gentrified redevelopment project; (3) gated communities in Texas and New York and cooperatives in New York, reclaiming public space and confronting race and class segregation created by neoliberal enclosure and securitization.  相似文献   

13.
A variety of resistance training interventions are used to improve field sport acceleration (e.g., free sprinting, weights, plyometrics, resisted sprinting). The effects these protocols have on acceleration performance and components of sprint technique have not been clearly defined in the literature. This study assessed 4 common protocols (free sprint training [FST], weight training [WT], plyometric training [PT], and resisted sprint training [RST]) for changes in acceleration kinematics, power, and strength in field sport athletes. Thirty-five men were divided into 4 groups (FST: n = 9; WT: n = 8; PT: n = 9; RST: n = 9) matched for 10-m velocity. Training involved two 60-minute sessions per week for 6 weeks. After the interventions, paired-sample t-tests identified significant (p ≤ 0.05) within-group changes. All the groups increased the 0- to 5-m and 0- to 10-m velocity by 9-10%. The WT and PT groups increased the 5- to 10-m velocity by approximately 10%. All the groups increased step length for all distance intervals. The FST group decreased 0- to 5-m flight time and step frequency in all intervals and increased 0- to 5-m and 0- to 10-m contact time. Power and strength adaptations were protocol specific. The FST group improved horizontal power as measured by a 5-bound test. The FST, PT, and RST groups all improved reactive strength index derived from a 40-cm drop jump, indicating enhanced muscle stretch-shortening capacity during rebound from impacts. The WT group increased absolute and relative strength measured by a 3-repetition maximum squat by approximately 15%. Step length was the major limiting sprint performance factor for the athletes in this study. Correctly administered, each training protocol can be effective in improving acceleration. To increase step length and improve acceleration, field sport athletes should develop specific horizontal and reactive power.  相似文献   

14.
In order to estimate the isonymy structure of Spain, we studied surname distribution in 283 Spanish towns based on 3.625 million telephone users selected from 6.328 million users, downloaded from a commercial CD-ROM which contains all 13 million users in the country. Since in Spain the surname is made by the paternal and the maternal surname, it was possible to classify surnames according to parental origin. Two matrices of isonymy distances, one for paternal and one for maternal surnames, were constructed and tested for correlation with geographic distance. For the whole of Spain, Euclidean distance was significantly but weakly correlated with geographic distance both for paternal and maternal surnames, with r = 0.205 +/- 0.013 and r = 0.263 +/- 0.012, respectively. Two dendrograms of the 283 sampled towns were built from the two matrices of Euclidean distance. They are largely colinear. Four main clusters identified by the dendrograms are correlated with geography. Given the surname structure of Spain, we were able to calculate from isonymy and for each town 1). total or expressed inbreeding, 2). random or expected inbreeding, and 3). local inbreeding. Total inbreeding, F(IT), was highest in the North Atlantic regions and lowest along the Mediterranean Coast. The lowest levels were found in Andalusia, Catalunyia, Valencia, and Navarra. Random inbreeding, F(ST), had a similar geographical pattern. Local inbreeding, F(IS), was relatively uniform in the whole of Spain. In towns, random inbreeding dominates over local inbreeding. From the analysis, it emerges that the northwestern area of Spain is the most inbred.  相似文献   

15.
Situated along a corridor linking the Asian continent with the outer islands of the Pacific, Papua New Guinea has long played a key role in understanding the initial peopling of Oceania. The vast diversity in languages and unique geographical environments in the region have been central to the debates on human migration and the degree of interaction between the Pleistocene settlers and newer migrants. To better understand the role of Papua New Guinea in shaping the region's prehistory, we sequenced the mitochondrial DNA (mtDNA) control region of three populations, a total of 94 individuals, located in the East Sepik Province of Papua New Guinea. We analyzed these samples with a large data set of Oceania populations to examine the role of geography and language in shaping population structure within New Guinea and between the region and Island Melanesia. Our results from median‐joining networks, star‐cluster age estimates, and population genetic analyses show that while highland New Guinea populations seem to be the oldest settlers, there has been significant gene flow within New Guinea with little influence from geography or language. The highest genetic division is between Papuan speakers of New Guinea versus East Papuan speakers located outside of mainland New Guinea. Our study supports the weak language barriers to genetic structuring among populations in close contact and highlights the complexity of understanding the genetic histories of Papua New Guinea in association with language and geography. Am J Phys Anthropol 142:613–624, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

16.
Recent studies of Anopheles gambiae, the principal mosquito vector of malaria in Africa, suggested that the eastern Rift Valley and its surrounding areas act as a barrier to gene flow. To quantify the unique effect of these areas on gene flow, we measured genetic variation within and between populations from each side of the Rift. Low differentiation was measured between populations on each side of the Rift (mean FST < 0.008, mean RST < 0.002). However, high differentiation was measured across the Rift (mean FST = 0.104; mean RST = 0.032). Genetic diversity within populations was lower in eastern populations, suggesting that the effective population sizes (Ne) of these populations were lower than those of western populations. We partitioned the overall differentiation across the Rift into three factors: variation in Ne between populations contributed 7-20%; distance contributed 10-30%, and the remainder, corresponding to the unique effect of the Rift was 50-80%. The Rift's effect was highly significant based on FST. The greater sensitivity of FST in measuring differentiation indicated that drift and not mutation generated the differences between populations. Restricted gene exchange across several hundred kilometers on the face of intense human transportation implies that active mosquito dispersal is the major form of migration, and that migration is a multistep process, where step length is relatively short.  相似文献   

17.
Comparisons of the patterns of differentiation among genetic markers with different modes of inheritance can provide insights into patterns of sex-biased dispersal and gene flow. Here, we compare the patterns of differentiation in six microsatellite loci among eight northern breeding populations of the yellow warbler (Dendroica petechia) with results obtained with mitochondrial DNA. Significant but low levels of differentiation (overall FST = 0.014; overall RST = 0.015) were present across all populations. The level of differentiation is substantially less than that observed in the same samples based on mitochondrial DNA control region variation. The presence of low population imbalance index values and significant isolation-by-distance relationships for both FST and RST suggests that these populations are at evolutionary equilibrium and that the high degree of similarity between populations may be due to high levels of male-biased gene flow. This suggests that there may be significant but previously unappreciated differences in the long-distance and/or episodic dispersal behaviour of males and females in these birds.  相似文献   

18.
An important characteristic of the genetic structure of populations, random inbreeding (interpopulation variation), was evaluated on the basis of quasi-genetic markers (surnames). The following methodological issues are considered: estimation of random inbreeding using the coefficient of isonymy fr in a subdivided population; a comparison of inbreeding levels calculated on the basis of surname frequencies using fr and Wright's FST; a comparison of inbreeding estimates obtained on the basis of surnames and genetic markers; inbreeding variation in populations of the same hierarchical rank; and planning of genetic studies of a subdivided population. The population of Adygs (an indigenous ethnic group of Northern Caucasus) was examined as a model subdivided population. The population system of Adygs is hierarchical. Parameters of random inbreeding were examined at each level of the system "ethnic group==>tribe==>geographic group of auls==>aul." Frequencies of surnames were collected subtotally. Data on frequencies of 1340 surnames in 61 auls representing all Adyg tribes were analyzed. In total, 60,000 people were examined. The inbreeding estimates obtained on the basis of Wright's FST and the coefficient of isonymy fr virtually coincided: for Adygs in general, FST x 10(2) = 2.13 and fr x 10(2) = 2.09. At the same time, the inbreeding level exhibited marked differences among tribes: in Shapsugs, these differences were an order of magnitude higher than in Kabardins (fr x 10(2) = 2.53 and 0.25, respectively). The inbreeding estimates for auls differed by two orders of magnitudes: fr x 10(2) = 0.07 and fr x 10(2) = 7.88. An analysis of ten auls yielded fully coinciding inbreeding estimates based on quasi-genetic (fr x 10(2) = 0.60) and classical (FST x 10(2) = 0.69) gene markers. Computer maps of surname distributions in Adygs (1340 maps) were constructed for the first time ever. Based on these maps, the map of random inbreeding in the Adyg population was obtained.  相似文献   

19.
The distributions of surnames have been studied in 12 rural ethnic territorial groups of Sakha Republic (Yakutia). The populations studied are characterized by considerable accumulation of individual surnames, the surname spectra of representative of different ethnic groups living in the same area substantially overlapping. The random isonymy, migration index, surname diversity, and the surname distribution redundancy index display geographic and ethnic differences. The isonymy relationship coefficients calculated for representatives of individual ethnic groups (Yakuts, Evens, and Russians) and for total populations of the settlements studied are determined by the geographic distances between the compared populations and the intensity of migrations.  相似文献   

20.
Migrations, dynamics of the gametic structure of rural populations, and marriage structure with respect to birthplaces and inbreeding estimated from isonymy have been studied in the Ust-Aldan ulus (administrative district) of Sakha Republic (Yakutia). The villages studied (Byadi, Dyupsya, and Cheriktey) are characterized by intense migration; however, the migration radius is small (most migrations occur within the district). The rural populations studied differ in the intensities and directions of gamete flows and their dynamics. There is no substantial gamete flow into the Ust-Aldan population from outside Sakha Republic. About 50% of marriages contracted in this population are homolocal (between residents of the same district); the endogamy is low (15%). In most cases of heterolocal marriages (contracted between residents of different districts), one of the spouses is a local resident. The inbreeding estimated from isonymy is FTT = 0.002930 in Yakuts; it is mainly accounted for by the nonrandom component (FIS = 0.002232 and FST = 0.000700).  相似文献   

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