22 research outputs found
Genetic Analysis of Female Preference Functions as Function-Valued Traits
The genetic analysis of female preferences has been seen as a particularly challenging empirical endeavor because of difficulties in generating suitable preference metrics in experiments large enough to adequately characterize variation. In this article, we take an alternative approach, treating female preference as a function-valued trait and exploiting random-coefficient models to characterize the genetic basis of female preference without measuring preference functions in each individual. Applying this approach to Drosophila bunnanda, in which females assess males through a multivariate contact pheromone system, we gain three valuable insights into the genetic basis of female preference functions. First, most genetic variation was attributable to one eigenfunction, suggesting shared genetic control of preferences for nine male pheromones. Second, genetic variance in female preference functions was not associated with genetic variance in the pheromones, implying that genetic variation in female preference did not maintain genetic variation in male traits. Finally, breeding values for female preference functions were skewed away from the direction of selection on the male traits, suggesting directional selection on female preferences. The genetic analysis of female preference functions as function-valued traits offers a robust statistical framework for investigations of female preference, in addition to alleviating some experimental difficulties associated with estimating variation in preference functions
Rapid desiccation hardening changes the cuticular hydrocarbon profile of Drosophila melanogaster
Mate choice for genetic quality when environments vary: suggestions for empirical progress
Mate choice for good-genes remains one of the most controversial evolutionary processes ever proposed. This is partly because strong directional choice should theoretically deplete the genetic variation that explains the evolution of this type of female mating preferences (the so-called lek paradox). Moreover, good-genes benefits are generally assumed to be too small to outweigh opposing direct selection on females. Here, we review recent progress in the study of mate choice for genetic quality, focussing particularly on the potential for genotype by environment interactions (GEIs) to rescue additive genetic variation for quality, and thereby resolve the lek paradox. We raise five questions that we think will stimulate empirical progress in this field, and suggest directions for research in each area: 1) How is condition-dependence affected by environmental variation? 2) How important are GEIs for maintaining additive genetic variance in condition? 3) How much do GEIs reduce the signalling value of male condition? 4) How does GEI affect the multivariate version of the lek paradox? 5) Have mating biases for high-condition males evolved because of indirect benefits
Fostering metacognitive skills: A longitudinal cohort study
Metacognitive awareness, which is part of self regulated learning, includes the domains of knowledge of cognition and regulation of cognition. Students with effective metacognitive skills are more aware of their strengths and weaknesses and strive to further improve their learning skills. This longitudinal cohort study uses the Junior Metacognitive Awareness Inventory (Jr. MAI) to measure student metacognitive awareness across Years 7 to 10 in a north Queensland girls’ Catholic college
Corporate governance
Governance is largely about the decision-making process in a complex organization Shareholders (owners) delegate authority to professionals who have the managerial skills to increase shareholders’ wealth. As a consequence the contributors of a firm's capital base are usually different from the contributors of its management base. This separation of ownership from control has led to organizations establishing a system of corporate governance controls designed to discourage managers from pursuing objectives that fail to maximize shareholder wealth. These controls constitute the firm's corporate governance framework. Corporate governance controls are designed to monitor managers behavior or align the goals of management with the goals of shareholders.\ud
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In this chapter, a corporate governance framework is developed that outlines the roles and responsibilities of participants involved in governing the organization and portraying information to the capital market
The depletion of genetic variance by sexual selection
Sexually selected traits display substantial genetic variance [1, 2], in conflict with the expectation that sexual selection will deplete it [3-5]. Condition dependence is thought to resolve this paradox [5-7], but experimental tests that relate the direction of sexual selection to the availability of genetic variance are lacking. Here, we show that condition-dependent expression is not sufficient to maintain genetic variance available to sexual selection in multiple male sexually selected traits. We employed an experimental design that simultaneously determined the quantitative genetic basis of nine male cuticular hydrocarbons (CHCs) of Drosophila bunnanda, the extent of condition dependence of these traits, and the strength and direction of sexual selection acting upon them. The CHCs of D. bunnanda are condition dependent, with 18% of the genetic variance in male body size explained by genetic variance in CHCs. Despite the presence of genetic variance in individual male traits, 98% of the genetic variance in CHCs was found to be orientated more than 88 degrees away from the direction of sexual selection and therefore unavailable to selection. A lack of genetic variance in male traits in the direction of sexual selection may represent a general feature of sexually selected systems, even in the presence of condition-dependent trait expression