A study of morphological and genetic distance among four Indian villages of Nicaragua

The degree of biological difference between four native populations from Nicaragua has been sought by measuring their morphological distance (DM) and genetic distance (DG). The calculation methods proposed by Sanghvi (1953) were applied. DM is estimated by taking into account first a set of craniometric measurements DM (C), then a set of somatometric measurements DM (S), and finally by calculating both sets jointly DM (CS). Comparison is also carried out by measuring DM according to a set of 13 indices (7 cranial and 6 somatic ones) DM (I). The position acquired by each population with respect to the others differs according to its determination as DM (C) or DM (S). On the contrary, DM (CS) and DM (I) seem to yield identical results, though little comparable with those obtained by comparison carried out according to the traditional anthropological methods. Moreover, the position of the four populations for DM at various levels in no case corresponds to that obtained by the measurement of DG.     

Beta-globin gene cluster haplotype distribution in five Brazilian Indian tribes

Haplotypes derived from five polymorphic restriction sites in the beta-globin gene cluster were investigated in 139 individuals from five different Brazilian Indian tribes by the polymerase chain reaction (PCR). Eight haplotypes were identified. Haplotypes 2 (+????) and 6 (?++?+) were the most frequent and were common to all tribes. Their prevalences ranged from 60% to 93% and from 3% to 18%, respectively. Average heterozy-gosity measured by the Gini-Simpson index is markedly reduced among these Brazilian Indians when compared with Europeans (56%), but much less (8%) in relation to Asiatics, suggesting the absence of an important bottleneck effect in the early colonization of South America. The coefficient of gene differentiation (GST′) was estimated as 0.082 among six Brazilian Indian tribes, but when only three Tupi-Mondé-speaking tribes were considered, this estimate was reduced to 0.030. © 1995 Wiley-Liss, Inc.     

Genetic distance and gene diversity among linguistically different tribes of Mexican Indians.

Using gene frequency data for 14 genetic loci, genetic distances between 13 tribes of Mexican Indians belonging to 12 language groups were determined and a dendrogram was constructed. The genetic distance between tribes is correlated more with geographic proximity than with language affinity. The gene diversity (heterozygosity) of the total population was decomposed into the three components, i.e., the gene diversity between three main linguistic groups, the gene diversity between tribes within the main linguistic groups and the gene diversity within tribes. About 95% of the total gene diversity exists within tribes, the intergroup and intertribe components being only about 5%.     

Linkage disequilibria and haplotype structure of four SNPs of the interleukin 1 gene cluster in seven Asian Indian populations

Variation at four single nucleotide polymorphism (SNP) sites of the interleukin 1 (IL1) gene cluster was investigated among 280 unrelated individuals, representing 7 caste groups from the state of Karnataka, India, and one European American community of Boston, Massachusetts. Allele and haplotype frequencies, strength of linkage disequilibrium, and signatures of recombination varied considerably among populations. Variable community sizes and traditions of consanguinity may account for the observed variation.     

Population studies on southwestern Indian tribes. V. Tooth morphology as an indicator of biological distance

The value of phylogenetic comparisons between populations based on tooth morphology depends on a knowledge of the extent to which the observed morphological variation is genetic in origin. This knowledge can be derived unequivocally only from the analysis of family data. However, in the absence of such knowledge the ability of tooth morphology to distinguish biological differences can be evaluated directly by testing its discriminating power in practice on populations between which the degrees of genetic difference are already known. The results of such an evaluation show that different degrees of subjectivity of scoring are associated with different characters, but that moderately good correspondence between known genetic differences and differences based on tooth morphology can be achieved when characters showing the least subjectivity of scoring are used.     

Mutation rates from rare variants of proteins in Indian tribes

Summary Recent attempts to estimate mutation rates in man have resulted in some theoretical developments. Recently, Nei (1977) provided a new formula for estimating mutation rates from electrophoretically detected rare protein variants. His formula is applied here to estimate mutation rates from such variants among the Kadars of Kerala and five tribes of Andhra Pradesh in India. The estimates seem to differ from Nei's estimate on South American Indians by an order of magnitude, although the standard errors associated with such estimates are rather large.     

Performance comparison between k-tuple distance and four model-based distances in phylogenetic tree reconstruction

Phylogenetic tree reconstruction requires construction of a multiple sequence alignment (MSA) from sequences. Computationally, it is difficult to achieve an optimal MSA for many sequences. Moreover, even if an optimal MSA is obtained, it may not be the true MSA that reflects the evolutionary history of the underlying sequences. Therefore, errors can be introduced during MSA construction which in turn affects the subsequent phylogenetic tree construction. In order to circumvent this issue, we extend the application of the k-tuple distance to phylogenetic tree reconstruction. The k-tuple distance between two sequences is the sum of the differences in frequency, over all possible tuples of length k, between the sequences and can be estimated without MSAs. It has been traditionally used to build a fast ‘guide tree’ to assist the construction of MSAs. Using the 1470 simulated sets of sequences generated under different evolutionary scenarios, the neighbor-joining trees and BioNJ trees, we compared the performance of the k-tuple distance with four commonly used distance estimators including Jukes–Cantor, Kimura, F84 and Tamura–Nei. These four distance estimators fall into the category of model-based distance estimators, as each of them takes account of a specific substitution model in order to compute the distance between a pair of already aligned sequences. Results show that trees constructed from the k-tuple distance are more accurate than those from other distances most time; when the divergence between underlying sequences is high, the tree accuracy could be twice or higher using the k-tuple distance than other estimators. Furthermore, as the k-tuple distance voids the need for constructing an MSA, it can save tremendous amount of time for phylogenetic tree reconstructions when the data include a large number of sequences.     

Chemodiversity of exudate flavonoids in seven tribes of Cichorioideae and Asteroideae (Asteraceae)

Members of several genera of Asteraceae, belonging to the tribes Mutisieae, Cardueae, Lactuceae (all subfamily Cichorioideae), and of Astereae, Senecioneae, Helenieae and Heliantheae (all subfamily Asteroideae) have been analyzed for chemodiversity of their exudate flavonoid profiles. The majority of structures found were flavones and flavonols, sometimes with 6- and/or 8-substitution, and with a varying degree of oxidation and methylation. Flavanones were observed in exudates of some genera, and, in some cases, also flavonol- and flavone glycosides were detected. This was mostly the case when exudates were poor both in yield and chemical complexity. Structurally diverse profiles are found particularly within Astereae and Heliantheae. The tribes in the subfamily Cichorioideae exhibited less complex flavonoid profiles. Current results are compared to literature data, and botanical information is included on the studied taxa.     

A further study of genetic distance among Australian Aborigines: Nine tribes in the Northern Territory

Summary A study of genetic distance has been carried out between 9 Aboriginal tribes in the Northern Territory of Australia. The B statistic of Balakrishnan and Sanghvi (1968) was employed and the analysis was based on the variability demonstrated in 8 blood groups, serum protein and enzyme systems. The genetic distance relationships were found to be correlated with linguistic differences amongst the tribes as well as with the geographic distance separating them.

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Zusammenfassung Eine genetische Abstands-Studie von 9 Eingeborenen-Stämmen im nördlichen Australien wurde ausgeführt. Die B-Statistik von Balakrishnan u. Sanghvi (1968) wurde angewendet. Die Analyse geht von den Unterschieden aus, die in 8 Blutgruppen, im Serum-Protein und bei den Enzym-systemen demonstriert wurden. Die genetische Abstands-Verwandtchaft wurde mit linguistischen Unterschieden und mit der räumlichen Entfernung, in der die Stämme wohnen, in Beziehung gesetzt.

     

Microdemographic variation and family composition in four thai villages

Examination of Thai ethnographic materials highlights several problems in comparative analysis of social processes that are population linked. Marked differences in family composition among four Central Thai villages are shown to arise primarily from a common family system operating on different underlying sociocultural and demographic processes. Satisfactory analysis requires detailed demographic data, information on other sociocultural processes, and a formal model of family dynamics relating the demographic to the other kinds of data. Lack of even one of these three components may make comparison meaningless. Demographic anthropology and historical demography provide complementary data well suited to anthropological studies of social organization.     

A memetic-aided approach to hierarchical clustering from distance matrices: application to gene expression clustering and phylogeny

We propose a heuristic approach to hierarchical clustering from distance matrices based on the use of memetic algorithms (MAs). By using MAs to solve some variants of the Minimum Weight Hamiltonian Path Problem on the input matrix, a sequence of the individual elements to be clustered (referred to as patterns) is first obtained. While this problem is also NP-hard, a probably optimal sequence is easy to find with the current advances for this problem and helps to prune the space of possible solutions and/or to guide the search performed by an actual clustering algorithm. This technique has been successfully applied to both a Branch-and-Bound algorithm, and to evolutionary algorithms and MAs. Experimental results are given in the context of phylogenetic inference and in the hierarchical clustering of gene expression data.     

杨树无性系光合特征的研究

对新培育的金科系列的4个杨树无性系（3^#、6^#、8^#、9^#）的光合特征及净光合速率、水分利用效率与主要影响因子的关系进行了研究。结果表明：不同月份4个无性系的净光合速率的日进程一般在10:00左右达到峰值,然后逐渐降低;蒸腾速率日进程不尽一致;气孔导度在7:00～9:00出现峰值后,缓慢下降。在6～8月,4个无性系的净光合速率的总平均值(μmol CO₂·m^-2·s^-1)排序为：无性系9^#（8.53）>6^#>（7.21）3^#（6.47）>8^#（4.98）;蒸腾速率的总平均值(mmol H₂O·m^-2·s^-1)排序为：无性系9^#（3.74）>3^#（2.76）>6^#（1.76）>8^#（1.47）;水分利用效率的总平均值(mmol CO₂·mol^-1 H₂O)排序为：无性系8^#（4.77）>6^#（4.35）>3^#（2.99）>9^#（2.40）。4个无性系的净光合速率与水分利用效率的排序并不一致。9^#属于高光合、高蒸腾、低水分利用效率类型,8^#属低光合、低蒸腾、高水分利用效率类型。在6月份6^#无性系的净光合速率和水分利用效率与温度、湿度显著相关,3^#、8^#、9^#无性系与光合有效辐射和气孔导度密切相关。     

Partial correlation of distance matrices in studies of population structure

Anthropological studies of human population structure commonly compare various monogenic and polygenic (metric) distance matrices to distance matrices obtained from measures of geographical dispersion, linguistic differences, and migration patterns in an attempt to infer something about the effects of evolutionary factors (drift and differential selection, in particular). It is, though, commonly recognized that geography, language, and migration patterns may be intercorrelated due to the common effects of historical and social processes. Previous attempts to deal with the problems of assessing relative effects among such sets of intercorrelated factors using partial correlations have resulted in coefficients that are either not well defined or have no known sampling distribution or both. Here, we outline a general approach to partialling distance matrices that results in well-defined coefficients and valid significance testing procedures. Application of the matrix partialling methods to a variety of distance matrices obtained for a sample of eight ethnolinguistic groups from the Harvard Solomon Islands Expedition (Friedlaender et al., 1986) reveals a close association between language dissimilarity and dermatoglyphics controlling for geography, thus reinforcing earlier suggestions that dermatoglyphics, properly used, reflect historical relationships of groups in this region better than do anthropometry, odontometrics, or small batteries of blood polymorphisms.     

Allozymic variation in four Indian species of genusMus: A comparative analysis

The present study focusses on allozyme variation in the commensal house mouseMus musculus, the pygmy field miceM. booduga andM. terricolor, and the spiny mouseM. platythrix. Genetic heterozygosity was estimated using a set of 24 polymorphic biochemical genetic markers. The extent of variability present inM. booduga, M. terricolor andM. platythrix has been compared with that in theM. musculus complex. Levels of allozyme variation at species level indicate thatM. musculus has the maximum heterogeneity, followed byM. booduga andM. terricolor, whileM. platythrix shows comparatively homogeneous genetic make-up. Gene frequency data have been used to trace phylogenetic relationships among these four species.     

A morphometric study of the Thingbu-pa and population comparison with neighbouring Monpa tribes of Arunachal Pradesh, India

In the present study an attempt has been made to examine the morphometric characteristics of the adult males of the Thinbu-pa and the nature and extent of morphometric variation among four neighbouring Monpa groups of Arunachal Pradesh (India), namely the Panchen-pa, Dirang Monpa, Tawang Monpa and Kalaktang Monpa. For the sake of investigation altogether 14 anthropometric measurements (11 pertaining to head and face and 3 on the body as a whole) have been taken and 5 indices have been calculated. To obtain the distance values the methods of Penrose (1947, 1954) and El-Najjar (1978) have been followed. It is observed that the Thingbu-pa maintain far distance with the four neighbouring Monpa groups as well as the Panchen-pa also maintain far distance with the other four groups, while the Dirang Monpa, Tawang Monpa and Kalaktang Monpa maintain close distance among each other.