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Unrelated Males (unrelated + male)
Selected AbstractsY haplogroups and aggressive behavior in a Pakistani ethnic groupAGGRESSIVE BEHAVIOR, Issue 1 2009S. Shoaib Shah Abstract Studies show that personality dimensions such as aggression are influenced by genetic factors and that allelic variants located on the Y chromosome influence such behavior. We investigated polymorphisms on the male-specific region of the human Y chromosome in 156 unrelated males from the same ethnic background, who were administered the Punjabi translation of the Buss and Perry Aggression Questionnaire that measures four aspects that constitute aggressive behavior, i.e. physical aggression, verbal aggression, anger, and hostility. A value of .85 for Cronbach's coefficient , indicates considerable internal consistency and suggests that the psychometric properties of the aggression questionnaire can be adapted for the Pakistani population. A mean score±SD of 69.70±19.95 was obtained for the questionnaire. Each individual was genotyped following a phylogenetic hierarchical approach to define evolutionary Y haplogroups. Five Y haplogroups that are commonly found in Eurasia and Pakistan comprised 87% (n=136) of the population sample, with one haplogroup, R1a1, constituting 55% of the sampled population. A comparison of the total and four subscale mean scores across the five common Y haplogroups that were present at a frequency ,3% in this ethnic group revealed no overall significant differences. However, effect-size comparisons allowed us to detect an association of the haplogroups R2 (Cohen's d statistic=.448,.732) and R1a1 (d=.107,.448) with lower self-reported aggression mean scores in this population. Aggr. Behav. 35:68,74, 2009. © 2008 Wiley-Liss, Inc. [source] Sib-mating in the ant Plagiolepis pygmaea: adaptative inbreeding?JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 12 2009N. THURIN Abstract Multiple functional queens in a colony (polygyny) and multiple mating by queens (polyandry) in social insects challenge kin selection, because they dilute inclusive fitness benefits from helping. Colonies of the ant Plagiolepis pygmaea brash contain several hundreds of multiply mated queens. Yet, within-colony relatedness remains unexpectedly high. This stems from low male dispersal, extensive mating among relatives and adoption of young queens in the natal colony. We investigated whether inbreeding results from workers expelling foreign males, and/or from preferential mating between related partners. Our data show that workers actively repel unrelated males entering their colony, and that queens preferentially mate with related males. These results are consistent with inclusive fitness being a driving force for inbreeding: by preventing outbreeding, workers reduce erosion of relatedness within colonies due to polygyny and polyandry. That virgin queens mate preferentially with related males could result from a long history of inbreeding, which is expected to reduce depression in species with regular sibmating. [source] For richer or for poorer: Marriage as an antipoverty strategyJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 4 2002Adam Thomas This study examines the effects of changes in family structure on children's economic well-being. An initial shift-share analysis indicates that, had the proportion of children living in female-headed families remained constant since 1970, the 1998 child poverty rate would have been 4.4 percentage points lower than its actual 1998 level of 18.3 percent. The March 1999 Current Population Survey is then used to conduct a second analysis in which marriages are simulated between single mothers and demographically similar, unrelated males. The microsimulation analysis addresses some of the shortcomings of the shift-share approach by making it possible to account for the possibility of a shortage of marriageable men, to control for unobservable differences between married men and women and their unmarried counterparts, and to measure directly the effects of increases in marriage on the economic well-being of children. Results from the microsimulation analysis suggest that, had the proportion of children living in female-headed families remained constant since 1970, the child poverty rate would have been 3.4 percentage points lower than its actual 1998 level. Among children whose mother participated in a simulated marriage, the poverty rate would have fallen by almost two-thirds. © 2002 by the Association for Public Policy Analysis and Management. [source] Recrudescence of sexual activity in a colony of the Mashona mole-rat (Cryptomys darlingi): an apparent case of incest avoidanceJOURNAL OF ZOOLOGY, Issue 2 2001M. Herbst Abstract Colonies of the Mashona mole-rat Cryptomys darlingi are founded from a single reproductive pair of animals that are genetically unrelated by descent. All non-reproductive animals are the progeny of the reproductive pair. Non-reproductive colony members do not seem to be suppressed from reproduction at the level of the pituitary. In colonies in which the reproductive female is removed or dies, there is strict incest avoidance and the colony remains reproductively quiescent. Reinstatement of sexual activity in a queenless colony may be brought about in the laboratory by the introduction of unfamiliar and unrelated adult males. In the queenless colony under study, there was a marked change in the dominance hierarchy with an increase in Landau's index of linearity from 0.61 to 1.0 on the introduction of two unrelated males. The two new males became the most dominant within the colony. All previously non-reproductive females exhibited heightened urinary oestradiol 17, and progesterone concentrations on the introduction of the males. However, it was only the older and most dominant non-reproductive female that became the new reproductive female and produced a litter of three pups 70 days after the initial introduction. [source] Do marker-based paternity assignments favour heterozygous and unrelated males?MOLECULAR ECOLOGY, Issue 9 2010JINLIANG WANG Abstract Genetic marker-based parentage analyses are widely applied to studies of natural populations in the fields of evolutionary biology, conservation biology and ecology. When the same markers used in a parentage analysis are used together with the inferred parentage in a downstream analysis, such as the analysis of mate choice in terms of heterozygosity or relatedness, a bias may be incurred because a subset of the genotypes are favoured in parentage assignments or non-exclusions. A previous simulation study shows that exclusion-based paternity analyses are biased in favour of heterozygous males, and males less related to the mothers than expected under random mating. In this study, I investigated the biases of genetic paternity analyses achieved by both exclusion- and likelihood-based methods, using both analytical and simulation approaches. It is concluded that while both exclusion- and likelihood-based methods can lead to biased paternity assignments or non-exclusions in favour of a subset of genotypes, the bias is not consistently towards heterozygous males or males apparently less related to mothers. Both the direction and extent of the bias depend heavily on the allele frequency distribution and the number of markers, the methods used for paternity assignments, and the estimators of relatedness. There exist important differences in the patterns of the biases between exclusion- and likelihood-based paternity analysis methods. It is concluded that the markers, except when they are highly informative to yield accurate paternity assignments or exclusions, should be split into two subsets which are used separately in the paternity and downstream analyses. [source] | ||||||||||