Biological Sciences A08, University of Sydney, Sydney, NSW, Australia.
Evolutionary and Behavioural Ecology Associate Research Unit, CSIC, Natural History Museum of Barcelona, P. Picasso s/n, 08003 Barcelona, Spain.
Sci Total Environ. 2015 Nov 1;532:512-6. doi: 10.1016/j.scitotenv.2015.06.021. Epub 2015 Jun 20.
Metals are naturally found in the environment but are also emitted through anthropogenic activities, raising some concerns about the potential deleterious effects of these elements on wildlife. The potential effects of metals on bird coloration have been the focus of several recent studies since animal colored-signals often reflect the physiology of their bearers and are thus used by animals to assess the quality of another individual as a mate or competitor. These studies have shown that the melanin pigmentation seems to be positively associated and the carotenoid-based coloration negatively associated with metal exposure in wild birds. Although these studies have been very useful to show the associations between metal exposure and coloration, only few of them have actually quantified the levels of metal exposure at the individual level; always focusing on one or two of them. Here, we measured the concentrations of eight metals in great tits' feathers and then assessed how these levels of metals were associated with the carotenoid and melanin-based colorations. We found that the melanin pigmentation was positively associated with the copper concentration and negatively correlated with the chromium concentration in feathers. In addition, we have shown that the carotenoid-based coloration was negatively associated with the feather's mercury concentration. This study is the first one to identify some metals that might affect positively and negatively the deposition of melanin and carotenoid into the plumage of wild birds.
金属在环境中自然存在，但也通过人为活动排放，这引起了人们对这些元素对野生动物潜在有害影响的一些关注。由于动物的彩色信号通常反映了它们携带者的生理状况，因此动物会利用这些信号来评估另一个个体作为配偶或竞争者的质量，因此金属对鸟类颜色的潜在影响一直是最近几项研究的重点。这些研究表明，黑色素沉着似乎与金属暴露呈正相关，而基于类胡萝卜素的颜色与金属暴露呈负相关。尽管这些研究对于表明金属暴露与颜色之间的关联非常有用，但实际上只有少数研究在个体水平上真正量化了金属暴露的水平；总是关注其中的一两个。在这里，我们测量了大山雀羽毛中的八种金属浓度，然后评估了这些金属水平与基于类胡萝卜素和黑色素的颜色之间的关联。我们发现黑色素沉着与羽毛中的铜浓度呈正相关，与铬浓度呈负相关。此外，我们还表明，基于类胡萝卜素的颜色与羽毛中的汞浓度呈负相关。这项研究首次确定了一些可能对野生鸟类羽毛中黑色素和类胡萝卜素沉积产生正向和负向影响的金属。
