Ranking Of Traits Research Articles

Relative contributions of crown and phenological traits to growth of a pseudo-backcross pine family ((slash × loblolly) × slash) and its pure species progenitors

One pseudo-backcross [(slash × loblolly) × slash] (BC1) and open-pollinated families of the pure species progenitors were established in a single test in North Central Florida. Multivariate analysis was used to estimate the intra-trait correlation among the taxa, and path analyses were used to determine the relative contributions of crown architectural and phenological traits to first-year height growth. The multivariate analysis indicated that BC1, slash, and loblolly pine have different relationships among the traits studied, suggesting that a separate path analysis was required for each taxon. Path analysis coefficients of determination of the final models were 0.69, 0.73, and 0.65 for the pseudo-backcross, loblolly, and slash pine families, respectively. The ranking of traits by relative magnitude of effect on total growth was, for the pseudo-backcross crown projected area (CPA), fascicle length (FL), number of nodes (NN), number of branches (NB), number of needles per fascicle (NF), and fascicle diameter. For loblolly, this was CPA, NB, FL, NN, NF, initiation, and specific leaf area. For slash, this was CPA, NN, FL, NF, and NB. The study indicated that all crown traits considered in the path analysis had moderate effects on first-year height growth, with the exceptions of the consistently large effect of CPA and the minimal effect of the phenological traits.

Latitudinal variation in morphological traits of the genus Pinus and its relation to environmental and phylogenetic signals

Background: Broad-scale analysis of interspecific trait variation is a fundamental approach in comparative ecology to investigate general species–environment relationships, but inferences from environmental and phylogenetic signals are still controversially discussed. Aims: The aim of this study was to globally analyse the genus Pinus and the interspecific variation of morphological traits with latitude as a surrogate of broad-scale environmental changes, and to compare latitudinal trait correlations with biogeographic, environmental and phylogenetic signals in trait variation. Methods: Based on native range maps of 103 Pinus species, the latitudinal correlations of nine morphological traits, including needle characters, cone length and tree height were calculated. Principal component analysis was used to explore trait covariation. Variation partitioning was applied to disentangle environmental and phylogenetic signals in trait variation. Results: Strong latitudinal correlations were detected for traits, such as needle length:width ratio or needle longevity, with similar trends for different taxonomic species subsets and geographic regions. Strong latitudinal correlations were related to a decrease in the pure phylogenetic signal and to an increase in the phylogenetically structured environmental variation (PSEV), whereas the pure environmental signal was almost negligible. Conclusions: Besides a ranking of traits that differ in environmental and phylogenetic signals, our results showed a general relationship between increasing latitudinal trait correlation and an increase in PSEV, which indicates phylogenetic niche conservatism. Thus, for the investigated morphological traits of the genus Pinus both environmental and phylogenetic signals are directly linked by PSEV to broad-scale spatial patterns in trait variation.

Defining desired genetic gains for rainbow trout breeding objective using analytic hierarchy process1

Distributing animals from a single breeding program to a global market may not satisfy all producers, as they may differ in market objectives and farming environments. Analytic hierarchy process (AHP) is used to estimate preferences, which can be aggregated to consensus preference values using weighted goal programming (WGP). The aim of this study was to use an AHP-WGP based approach to derive desired genetic gains for rainbow trout breeding and to study whether breeding trait preferences vary depending on commercial products and farming environments. Two questionnaires were sent out. Questionnaire-A (Q-A) was distributed to 178 farmers from 5 continents and used to collect information on commercial products and farming environments. In this questionnaire, farmers were asked to rank the 6 most important traits for genetic improvement from a list of 13 traits. Questionnaire B (Q-B) was sent to all farmers who responded to Q-A (53 in total). For Q-B, preferences of the 6 traits were obtained using pairwise comparison. Preference intensity was given to quantify (in % of a trait mean; G%) the degree to which 1 trait is preferred over the other. Individual preferences, social preferences, and consensus preferences (Con-P) were estimated using AHP and WGP. Desired gains were constructed by multiplying Con-P by G%. The analysis revealed that the 6 most important traits were thermal growth coefficient (TGC), survival (Surv), feed conversion ratio (FCR), condition factor (CF), fillet percentage (FIL%), and late maturation (LMat). Ranking of traits based on average Con-P values were Surv (0.271), FCR (0.246), TGC (0.246), LMat (0.090), FIL% (0.081), and CF (0.067). Corresponding desired genetic gains (in % of trait mean) were 1.63, 1.87, 1.67, 1.29, 0.06, and 0.33%, respectively. The results from Con-P values show that trait preferences may vary for different types of commercial production or farming environments. This study demonstrated that combination of AHP and WGP can be used to derive desired gains for a breeding program and to quantify differences due to variations market demand or production environment.

Farmers’ participatory selection for early bulking cassava genotypes in semi-arid Eastern Kenya

Cassava is an important food security crop in semi-arid, Eastern Kenya, but production is constrained by planting late bulking landraces. Therefore, farmer participatory variety selection was initiated with the aim of identifying early bulking varieties with preferred root qualities. Four popular local varieties were crossed with six early-bulking varieties selected from IITA germplasm in a North Carolina II mating scheme. The resultant 225 cloned F1 progenies were evaluated for early bulking in a 15 x 15 simple lattice design with two replications at KARI-Kiboko farm in Eastern Kenya. Sixty-five farmers participated in the selection of early bulking genotypes with preferred root qualities during the second and third harvests at 7 and 8 months after planting. At 7 months, there was a significant variation among genotypes for root bulking, cyanide content, dry matter content, harvest index and root number. Farmers subjected all the genotypes to a preference test and selected 30 genotypes (13%), which combined early-bulking and high root quality. A selection index based on farmers’ ranking of agronomic traits was then imposed on the selected 30 genotypes to identify those that were superior in both agronomic and end-user traits for possible release and advancement. The selected genotypes were all significantly superior to the parents. The top 10 genotypes displayed above average performance for all agronomic traits. Involving farmers in selection helped to identify early bulking genotypes with end-user root qualities that could/should ultimately accelerate their adoption. Key words: Cassava, participatory, early bulking.

Mate preferences among the Shuar of Ecuador: trait rankings and peer evaluations

A large body of research has examined sex differences in mate preferences, but very little of such work has been conducted in small-scale societies. Study 1 explored women's and men's mate preferences within a modern hunter-horticulturalist population in Amazonian Ecuador. In contrast to patterns documented in much of the existing literature, women and men from three Shuar villages were nearly identical in their stated preferences for physical attractiveness and resource-related traits, and physical attractiveness was ranked at the bottom among 19 traits. Study 2 examined the relationship between unmarried Shuar participants' assessments of the personal characteristics of known peers and their assessments of those peers as desirable long-term partners. When assessed using this method, physical attractiveness appeared to weigh much more heavily into Shuar evaluations of partner desirability, and a sex difference emerged in the preference for resource-related traits. Overall, there were substantial differences between individuals' stated preferences and their preferences as revealed in peer ratings. Across both measurement techniques, however, Shuar women and men were very similar in their preferences for physical attractiveness. These results raise questions about the universality of sex differences in mate preferences documented in the existing literature.

The Preferred Traits of Mates in a Cross-National Study of Heterosexual and Homosexual Men and Women: An Examination of Biological and Cultural Influences

BBC Internet survey participants (119,733 men and 98,462 women) chose from a list of 23 traits those they considered first, second, and third most important in a relationship partner. Across all participants, the traits ranked most important were: intelligence, humor, honesty, kindness, overall good looks, face attractiveness, values, communication skills, and dependability. On average, men ranked good looks and facial attractiveness more important than women did (d = 0.55 and 0.36, respectively), whereas women ranked honesty, humor, kindness, and dependability more important than men did (ds = 0.23, 0.22, 0.18, and 0.15). Sexual orientation differences were smaller than sex differences in trait rankings, but some were meaningful; for example, heterosexual more than homosexual participants assigned importance to religion, fondness for children, and parenting abilities. Multidimensional scaling analyses showed that trait preference profiles clustered by participant sex, not by sexual orientation, and by sex more than by nationality. Sex-by-nation ANOVAs of individuals' trait rankings showed that sex differences in rankings of attractiveness, but not of character traits, were extremely consistent across 53 nations and that nation main effects and sex-by-nation interactions were stronger for character traits than for physical attractiveness. United Nations indices of gender equality correlated, across nations, with men's and women's rankings of character traits but not with their rankings of physical attractiveness. These results suggest that cultural factors had a relatively greater impact on men's and women's rankings of character traits, whereas biological factors had a relatively greater impact on men's and women's rankings of physical attractiveness.

Functional traits of woody plants: correspondence of species rankings between field adults and laboratory‐grown seedlings?

Abstract.Research into interspecific variation in functional traits is important for our understanding of trade‐offs in plant design and function, for plant functional type classifications and for understanding ecosystem responses to shifts in species composition. Interspecific rankings of functional traits are a function of, among other factors, ontogenetic or allometric development and environmental effects on phenotypes. For woody plants, which attain large size and long lives, these factors might have strong effects on interspecific trait rankings. This paper is the first to test and compare the correspondence of interspecific rankings between laboratory grown seedlings and field grown adult plants for a wide range of functional leaf and stem traits. It employs data for 90 diverse woody and semiwoody species in a temperate British and a (sub)Mediterranean Spanish flora, all collected according to a strict protocol. For 12 out of 14 leaf and stem traits we found significant correlations between the species ranking in laboratory seedlings and field adults. For leaf size and maximum stem vessel diameter > 50 % of variation in field adults was explained by that in laboratory seedlings. Two important determinants of plant and ecosystem functioning, specific leaf area and leaf N content, had only 27 to 36 and 17 to 31 % of variation, respectively, in field adults explained by laboratory seedlings, owing to subsets of species with particular ecologies deviating from the general trend. In contrast, interspecific rankings for the same traits were strongly correlated between populations of field adults on different geological substrata. Extrapolation of interspecific trait rankings from laboratory seedlings to adult plants in the field, orvice versa, should be done with great caution.

Explorations of construct validity in a combined managerial and personality assessment programme

A combined programme entailing separate managerial and personality assessment staffs was employed to explore the construct validity of managerial performance dimensions. For a sample of 119 MBA (Master of Business Administration) candidates, principal components analysis of mean ratings on 14 managerial performance dimensions identified a Strategic Managerial Style (SMS) (e.g. decision making, fact‐finding) and an Interpersonal Managerial Style (IMS) (e.g. oral communication, initiative). Among independent scorings for the managerial assessment procedures, performance on the in‐basket exercise best predicted SMS while performance in the leaderless group discussion best predicted IMS. Trait rankings, Adjective Check List impressions, and Q sort portraits recorded by the personality assessment staff were related to the SMS and IMS as well as to the managerial assessment staff's overall judgments of Managerial Potential (MP). Of the domains of the five‐factor model of personality dimensions, the SMS trait descriptors were most characterized by Conscientiousness and Openness, the IMS by Extraversion, Openness and low Agreeableness, and the MP by Extraversion and Openness. Implications were drawn for the relation of managerial assessment centre measures to concurrent personality measures and for alternative predictive models of career outcome criteria.

Improving the Validity of Letters of Recommendation: An Investigation of Three Standardized Reference Forms

Although letters of recommendation are (LORs) widely used, little research has examined how accurately they predict job performance. The few existing studies have yielded mixed results, and meta-analytic estimates of validity range from .14 to .27 (Hunter & Hunter, 1984; Reilly & Chao, 1982). This investigation was designed to improve predictive validity by developing a standardized reference form and evaluating 3 different rating formats: Multi-Item scales, Relative Percentile Method (RPM) scales, and Global Trait Rankings. A total of 520 individuals applied to the Canadian military, and 544 LORs were obtained. Complete predictor and criterion data were available for 57 participants. Regression analyses indicated that the validity of the RPM rating format (R2(adj) = .18; R(adj) = .42) was substantially higher than previous estimates of LOR validity. The 2 remaining methods produced nonsignificant results. Limitations of the study, suggestions for future research, and implications for the field are discussed.

Occupation and Physical Punishment: A Response to Straus

In the preceding paper, Straus reports no difference between and parents in their use of physical punishment. He interprets this as showing parents of upwardly mobile children have tended to use child rearing practices (in this case, avoidance of physical punishment). In so doing, they help to equip the child with personality traits appropriate for the child's stratum of destination. However, his interpretation ignores the fact just over half of both and parents did use physical punishment. It raises the intriguing question of accounting for the half who used physical punishment, especially among the class. Perhaps Straus' findings can be explained by the fact his measure of social is based on dividing the population into a working class who performed manual jobs and a middle class who did non-manual work. However, with the increased affluence and technological complexity of society, the dichotomy of manual versus non-manual may no longer validly serve as a basis for differentiating life styles and especially child rearing patterns. Even with education and occupational title held constant, there are differences inherent within the framework of one's occupation which may show a closer relationship to child rearing patterns. For example, consider three mechanical engineers, all with a M.S. degree. One engineer is a theoretically oriented college professor, another is in an executive administrative position, and the third is employed in a large factory installation and spends much of his time actually with and redesigning machinery. On a traditional social index such as Hollingshead-Redlich two factor index, all three engineers would be given the same social class. But the tasks required by their particular jobs, which (in line with Kohn's theory) are considered to influence the way they socialize their children, differ considerably. Therefore, it is suggested what appears to be a narrowing of the gap between the and in child rearing patterns (Bronfenbrenner, 1961) results from the fact in an affluent i dustrial society the dichotomy of manual-non manual is no longer the highly differentiating factor it may once have been. Consequently, attempts to relate child rearing techniques to social may suppress an actual relationship between occupation and child rearing techniques. What is needed is a system of conceptualizing occupations in a way which more directly reflects the demand characteristics of an occupation. The taxonomy of 'occupational environments introduced by Holland (1959) in a paper on vocational choice theory, seems to be one such possibility. Holland's categories take into account the particular interpersonal, verbal and motor skills utilized in an individual's job, and thus cut across social boundaries. To provide a preliminary examination of the hypothesis child rearing patterns are related to the tasks which one does in his job, a small exploratory study was undertaken. Using students in an undergraduate sociology class, the Straus study was replicated, and the data was analyzed, step by step, according to the procedures outlined in his paper. Although the sample size was small(N = 17), he results obtained were so similar to those reported by Straus, there exists a measure of confidence the same phenomena are being reported. For example, 53 percent of the respondents in the replication reported use or threat of use of physical punishment. And the rankings of traits which parents consider desirable in their children are also consistent with those reported by Straus. As in the Straus study, there were no important differences between social classes (mean physical punishment scores of 1.02 for the and 1.00 for the class). Finally, in agreement with Straus, parents who ranked as a desired characteristic (first to third in ranking) had mean physical punishment scores of 1.50, compared to 0.22 for parents who ranked obedience from fourth to last. When that I think for myself was ranked first to third, the mean physical punishment score was 0.18, compared to 0.95 when this charac-