No abstract

Individual variation in achromatic plumage reflectance of male Blackcapped Chickadees (Poecile atricapillus) is correlated with social rank and reproductive success, suggesting it may play an important role in sexual signaling. We asked whether female chickadees could assess male quality based on plumage, in the absence of information about relative social dominance. Sexually mature but inexperienced females captured during the pair formation period in late fall and early winter were presented with a choice of two unfamiliar, sexually experienced males in separate compartments of an outdoor mate choice arena. Following each preference trial, we released the males into a single compartment and scored their pairwise dominance interactions. In 10 of 11 trials, females spent significantly more time with the male subsequently identified as dominant, despite not witnessing the males interact. Spectral analysis of male plumage reflectance revealed that UV-chroma of dark body regions (bib, cap and mantle) was significantly greater in dominant, preferred males and that dominant, preferred males had significantly brighter white cheek patches. There were no differences in vocalization rates of preferred and nonpreferred males. These results show that female chickadees can rapidly assess unfamiliar males based on visual cues, and suggest that variation in achromatic plumage functions in sexual signaling.

With the proliferation of short term study abroad programs at institutions of higher education, there is a need for more rigorous assessment of how these pr ograms contribute to intercultural learning. This article presents a multi institutional comparative study of students’ intercultural learning in six short term study abroad programs in Canada and the U nited S tates , employing both quantitative and qualitat ive methods. The study combines pre and post IDI survey scores with a qualitative analysis of student writing to present evidence about the impact of specific program features on students’ intercultural learning, as well as an analysis of how the students themselves make sense of their experiences abroad. We argue that the extent of pre departure intercultural training has a positive relationship with intercultural learning outcomes. Additionally, we present evidence that service learning opportunities and intra group dynamics contribute to students’ intercultural competence. We conclude that mixed methods analysis provides the most effective way of identifying how different program factors contribute to intercultural growth, when that growth occurs in a pr ogram cycle, and how program leaders can provide effective intercultural interventions to best facilitate student learning abroad.

We examined sex allocation patterns in island and mainland populations of cooperatively breeding white-winged fairy-wrens. The marked differences in social structure between island and mainland populations, in addition to dramatic plumage variation among males both within and between populations, provided a unique situation in which we could investigate different predictions from sex allocation theory in a single species. First, we test the repayment (local resource enhancement) hypothesis by asking whether females biased offspring sex ratios in relation to the assistance they derived from helpers. Second, we test the male quality (attractiveness) hypothesis, which suggests that females mated to attractive high-quality males should bias offspring sex ratios in favor of males. Finally, we test the idea that females in good condition should bias offspring sex ratios toward males because they are able to allocate more resources to offspring, whereas females in poor condition should have increased benefits from producing more female offspring (Trivers-Willard hypothesis). We used molecular sexing techniques to assess total offspring sex ratios of 86 breeding pairs over 2 years. Both offspring and first brood sex ratios were correlated with the pair-male's body condition such that females increased the proportion of males in their brood in relation to the body condition (mass corrected for body size) of their social partner. This relation was both significant and remarkably similar in both years of our study and in both island and mainland populations. Although confidence of paternity can be low in this and other fairy-wren species, we show how this finding might be consistent with the male quality (attractiveness) hypothesis with respect to male condition. There was no support for the repayment hypothesis; the presence of helpers had no effect on offspring sex ratios. There was weak support for both the male quality (attractiveness) hypothesis with respect to plumage color and the maternal condition hypothesis, but their influence on offspring sex ratios was negligible after controlling for the effects of pair-male condition.

With increasing demands for universities to create graduates that are numerically and scientifically literate, it is important to determine effective ways to engage students so that they can acquire these literacies. Using an undergraduate, interdisciplinary course that focused on scientific and mathematical literacy, I examined how contextualization influenced students' abilities to build connections between their learning and their lives. In their written reflections, students connected course concepts with their social lives, academic pursuits and global or societal issues without specific prompting. I suggest that contextualization combined with reflection allows students to illustrate their understanding and apply this knowledge to novel scenarios.