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3. Biology of the Rufous Hornero, from mechanisms to behavioral ecology: a potential Neotropical model species?

Author

Mentesana, Lucia, Amador, Ana, Amorim, Paulo, Delhey, Kaspar, Diniz, Pedro, Mindlin Rosendo Fraga, Gabriel B., Reboreda, Juan C., Schaaf, Alejandro, Tassino, Bettina, and Adreani, Nicolas M.

Subjects
BIRD behavior, ANIMAL sexual behavior, BIRD ecology, RESEARCH questions, SONGBIRDS
Abstract

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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5. Neutral and selective drivers of colour evolution in a widespread Australian passerine

Author

Morales, Hernán E, Pavlova, Alexandra, Sunnucks, Paul, Major, Richard, Amos, Nevil, Joseph, Leo, Wang, Biao, Lemmon, Alan R, Endler, John A, and Delhey, Kaspar

Subjects
Climate Change Impacts and Adaptation, Biological Sciences, Ecology, Genetics, Environmental Sciences, Human Genome, adaptive, carotenoid, colour variation, melanin, neutral, path analysis, spatial autocorrelation, Earth Sciences, Biological sciences, Earth sciences, Environmental sciences
Abstract

AIM: Rump plumage coloration of the Eastern Yellow Robin (Eopsaltria australis), a widespread Australian songbird, varies from bright yellow in the tropical north to oliveâgreen in the temperate south. Here, we test whether colour variation: (1) correlates most strongly with neutral genetic variation and so is best explained by historical processes, (2) reflects selection associated with different visual environments (dense versus open habitats) and/or (3) reflects selection associated with climatic variation. LOCATION: Eastern Australia. METHODS: We quantified colour variation using reflectance spectrometry and visual models. We performed geographical cline analysis of colour and neutral genetic variation (genomeâwide single nucleotide polymorphisms). We tested for correlations of colour variation with climate, vegetation density, geographical location and genetic variation. We accounted for covariation and spatial autocorrelation, and conducted analyses at continental and regional spatial scales. RESULTS: Clinal variation of colour traits and neutral genetic markers were largely concordant. At the continental scale, colour variation was strongly associated with neutral genetic structure and geography, and to a lesser extent with environment. At the regional scale, environmental variation was a better predictor of colour variation than it was at the larger scale. MAIN CONCLUSION: At the continental scale, colour variation is strongly associated with largeâscale population history. In contrast, at the regional scale, where the influence of history and geography is weaker, environmental variation has a role in facilitating the maintenance of colour variation. Our results highlight the need to assess selective and neutral alternatives at multiple spatial scales when studying geographical variation.

Published
2017

31. When does early-life telomere length predict survival? A case study and meta-analysis

Author

Eastwood, Justin R., Dupoue, Andreaz, Delhey, Kaspar, Verhulst, Simon, Cockburn, Andrew, Peters, Anne, Eastwood, Justin R., Dupoue, Andreaz, Delhey, Kaspar, Verhulst, Simon, Cockburn, Andrew, and Peters, Anne

Abstract

Suboptimal conditions during development can shorten telomeres, the protective DNA caps on the end of chromosomes. Shorter early-life telomere length (TL) can indicate reduced somatic maintenance, leading to lower survival and shorter lifespan. However, despite some clear evidence, not all studies show a relationship between early-life TL and survival or lifespan, which may be due to differences in biology or study design (e.g., survival period measured). In superb fairy-wrens (Malurus cyaneus), we assessed whether early-life TL predicts mortality across different life-history stages (fledgling, juvenile, adult). However, in contrast to a similar study on a congener, early-life TL did not predict mortality across any life stage in this species. We then performed a meta-analysis including 32 effect sizes from 23 studies (15 birds and three mammals) to quantify the effect of early-life TL on mortality whilst taking into consideration potential sources of biological and methodological variation. Overall, the effect of early-life TL on mortality was significant, corresponding to a 15% reduction in mortality risk with each standard deviation increase in TL. However, the effect became weaker when correcting for publication bias. Contrary to our predictions, there was no evidence that effects of early-life TL on mortality varied with species lifespan or the period over which survival was measured. However, negative effects of early-life TL on mortality risk were pervasive throughout life. These results imply that effects of early-life TL on mortality are more likely to be context-dependent than age-dependent, although substantial power and publication bias issues highlight the need for more research.

Published
2023
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32. Which plumage patches provide information about condition and success in a female fairy-wren?

Author

Nolazco, Sergio, Delhey, Kaspar, Fan, Marie, Hall, Michelle L., Kingma, Sjouke A., Roast, Michael J., Teunissen, Niki, Peters, Anne, Nolazco, Sergio, Delhey, Kaspar, Fan, Marie, Hall, Michelle L., Kingma, Sjouke A., Roast, Michael J., Teunissen, Niki, and Peters, Anne

Abstract

Recent evidence suggests that female ornaments can commonly act as signals. However, how signaling functions might be affected by the tendency for reduced ornament elaboration in relation to males is less well-understood. We address this in mutually ornamented purple-crowned fairy-wrens. We investigated putatively ornamental (tail, ear coverts, crown) and non-ornamental (throat, back) plumage patches in females and compared our findings to previous studies in males. Both sexes have brown backs, buff-white throats, and turquoise-blue tails (bluer in males), while ear coverts are rufous in females and black in males. Both sexes also have a seasonal crown (slate-gray in females, black-and-purple in males). Dominant (breeder) females expressed more complete and grayer (more ornamented) crowns, although variation in coloration should not be discriminable by individuals. Unexpectedly, subordinates showed more colorful (saturated) rufous ear coverts, which should be discriminable. Condition-dependence was only evident for crown completeness (% slate-gray cover). Females with more reddish-brown backs were more reproductively successful. Variation in plumage characteristics did not explain differential allocation by mates or chances of gaining dominance. Our outcomes were not entirely consistent with findings in males. The most notable disparity was for the crown, a signal used in male-male competition that in females seems to be expressed as an incomplete version of the male crown that is not associated with fitness benefits. Our study shows that in a species, multiple traits can vary in their information content and that female ornaments can sometimes be less informative than in males, even those that are produced seasonally.

Published
2023

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