Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA.
Department of Biology, Agnes Scott College, Decatur, GA, 30030, USA.
Sci Rep. 2018 Oct 19;8(1):15533. doi: 10.1038/s41598-018-33948-0.
Animals use morphological signals such as ornamental traits or weaponry to mediate social interactions, and the extent of signal trait elaboration is often positively associated with reproductive success. By demonstrating relationships between signal traits and fitness, researchers often make inferences about how behaviour operates to shape those outcomes. However, detailed information about fine-scale individual behaviour, and its physiological basis, can be difficult to obtain. Here we show that experimental manipulations to exaggerate a signal trait (plumage colour) and concomitant changes in testosterone and stress-induced corticosterone levels altered social interactivity between manipulated males and their social mates. On average, darkened males did not have higher levels of interactivity than unmanipulated males; however, males who experienced a greater shift in colour (pale to dark), a larger, positive change in testosterone levels, and a dampened stress-induced corticosterone response had a larger increase in the number of interactions with their social mate post-manipulation compared to pre-manipulation. This work provides new insights into the integration and real-time flexibility of multivariate phenotypes and direct evidence for the role of social interactions in pair bond maintenance.
动物利用形态信号（如装饰性特征或武器）来调节社会互动，信号特征的精细程度通常与繁殖成功呈正相关。通过展示信号特征与适应性之间的关系，研究人员通常可以推断行为如何影响这些结果。然而，关于个体行为的详细信息及其生理基础往往难以获取。在这里，我们表明，通过实验夸大一个信号特征（羽毛颜色）并伴随睾丸酮和应激诱导的皮质酮水平的变化，会改变受操纵雄性与其社会配偶之间的社交互动性。平均而言，颜色变深的雄性与未受操纵的雄性相比，其社交互动性并没有更高；然而，经历颜色变化更大（从浅色变为深色）、睾丸酮水平更大的正向变化、应激诱导的皮质酮反应更缓和的雄性，在受操纵后与社会配偶的互动次数比受操纵前增加得更多。这项工作为多变量表型的整合和实时灵活性提供了新的见解，并为社会互动在伴侣关系维持中的作用提供了直接证据。
