17 research outputs found
Breeding Experience and the Heritability of Female Mate Choice in Collared Flycatchers
Heritability in mate preferences is assumed by models of sexual selection, and preference evolution may contribute to adaptation to changing environments. However, mate preference is difficult to measure in natural populations as detailed data on mate availability and mate sampling are usually missing. Often the only available information is the ornamentation of the actual mate. The single long-term quantitative genetic study of a wild population found low heritability in female mate ornamentation in Swedish collared flycatchers. One potentially important cause of low heritability in mate ornamentation at the population level is reduced mate preference expression among inexperienced individuals.Applying animal model analyses to 21 years of data from a Hungarian collared flycatcher population, we found that additive genetic variance was 50 percent and significant for ornament expression in males, but less than 5 percent and non-significant for mate ornamentation treated as a female trait. Female breeding experience predicted breeding date and clutch size, but mate ornamentation and its variance components were unrelated to experience. Although we detected significant area and year effects on mate ornamentation, more than 85 percent of variance in this trait remained unexplained. Moreover, the effects of area and year on mate ornamentation were also highly positively correlated between inexperienced and experienced females, thereby acting to remove difference between the two groups.The low heritability of mate ornamentation was apparently not explained by the presence of inexperienced individuals. Our results further indicate that the expression of mate ornamentation is dominated by temporal and spatial constraints and unmeasured background factors. Future studies should reduce unexplained variance or use alternative measures of mate preference. The heritability of mate preference in the wild remains a principal but unresolved question in evolutionary ecology
Additive genetic variance of quantitative traits in natural and pond-bred populations of the Lake Tanganyika cichlid Tropheus moorii
Genetic diversity and parasite prevalence in two species of bumblebee
Many bumblebee species have been suffering from significant declines across their ranges in the Northern Hemisphere over the last few decades. The remaining populations of the rare species are now often isolated due to habitat fragmentation and have reduced levels of genetic diversity. The persistence of these populations may be threatened by inbreeding depression, which may result in a higher susceptibility to parasites. Here we investigate the relationship between genetic diversity and prevalence of the parasitic mite Locustacarus buchneri in bumblebees, using the previously-studied system of Bombus muscorum and Bombus jonellus in the Western Isles of Scotland. We recorded L. buchneri prevalence in 17 populations of B. muscorum and 13 populations of B. jonellus and related the results to levels of heterozygosity. For B. muscorum, we found that prevalence of the mite was higher in populations with lower genetic diversity but there was no such relationship in the more genetically diverse B. jonellus. In contrast to population-level measures of genetic diversity, the heterozygosity of individual bees was not correlated with infection status. We suggest population-level genetic homogeneity may facilitate parasite transmission and elevate prevalence, with potential consequences for population persistence. © 2014 Springer International Publishing Switzerland
Host heterozygosity and genotype rarity affect viral dynamics in an avian subspecies complex
Ethical Leadership with Both “Moral Person” and “Moral Manager” Aspects: Scale Development and Cross-Cultural Validation
The importance of ethical leadership in organizations has been increasingly recognized, especially as a shield against unethical employee behaviors and corporate misconducts. Ethical leadership has been theorized to include two aspects: “moral person” and “moral manager.” This conceptualization resonates well with Chinese teachings of Confucius on leadership and management—namely xiuji (cultivating oneself) and anren (bringing the good to others). Based on the theoretical framework of ethical leadership, we develop and validate a new ethical leadership measure (ELM). Through qualitative studies (i.e., face-to-face interviews, open-ended surveys, and literature review) and five quantitative studies, we establish the reliability and convergent, discriminant, and predictive validities of the ELM in a Chinese context. In addition, using a US sample, we find that the ELM has partial measurement invariance across Chinese and American contexts.</p