色素着色在动物中普遍存在。它的进化和生态特征通常归因于主要颜料的性质;因此,大多数研究都集中在类胡萝卜素着色中的主要色素,如类胡萝卜素。然而,着色来自主要颜料和许多其他少数颜料,而后者的重要性被忽视了。这里,我们专注于卟啉,在鸟类羽毛中发现的一种“不常见”的色素,并在谷仓燕子Hirundorustica的羽毛颜色变化的背景下研究了其重要性。我们发现谷仓燕子的“基于pheomelanin的着色”在紫外线照射后褪色,这种效果在幼小燕子(雏鸟和雏鸟,here).我们还发现它不是主要的色素,pheomelanin,但是原卟啉IX色素在紫外线照射后显示出相同的脱色模式,尤其是幼小燕子的羽毛。事实上,羽毛中卟啉的含量在统计学上解释了上述年龄依赖性羽毛颜色的变化。目前的研究表明,少数色素,卟啉,解释季节内动态颜色变化,羽毛着色的生态特征。卟啉介导的快速颜色变化将有益于幼鸟,在独立前几周,羽毛颜色会影响父母的食物分配,但不是以后。未来的研究不应忽视这些次要但必需的色素及其进化和生态功能。
Pigmentary coloration is widespread in animals. Its evolutionary and ecological features are often attributed to the property of predominant pigments; therefore, most research has focused on predominant pigments such as carotenoids in carotenoid-based coloration. However, coloration results from predominant pigments and many other minority pigments, and the importance of the latter is overlooked. Here, we focused on porphyrin, an \"uncommon\" pigment found in bird feathers, and investigated its importance in the context of feather color changes in the barn swallow Hirundo rustica. We found that the \"
pheomelanin-based coloration\" of the barn swallow faded after the irradiation of UV light, and this effect was particularly strong in the feathers of young swallows (nestlings and fledglings, here). We also found that it is not the predominant pigment,
pheomelanin, but protoporphyrin IX pigment that showed the same pattern of depigmentation after the irradiation of UV light, particularly in the feathers of young swallows. In fact, the abovementioned age-dependent feather color change was statistically explained by the amount of porphyrin in the feathers. The current study demonstrates that a minority pigment, porphyrin, explains within-season dynamic color change, an ecological feature of feather coloration. The porphyrin-mediated rapid color change would benefit young birds, in which feather coloration affects the parental food allocation during a few weeks before independence, but not later. Future studies should not ignore these minor but essential pigments and their evolutionary and ecological functions.