Do trace metals influence visual signals? Effects of trace metals on iridescent and melanic feather colouration in the feral pigeon

Trace metals are chemical pollutants of prime concern nowadays given their implication in several human diseases and their noxious effects on wildlife. Previous studies demonstrated their negative (e.g. lead, cadmium) or positive (e.g. zinc) effects on body condition, immunity and reproductive success in birds. Because of their effects on bird condition, trace metals are likely to influence the production of condition-dependent plumage colours, that may be used in mate choice. In the feral pigeon Columba livia, we investigated iridescent colouration in response to lead and zinc experimental (i.e. metal supplementation in standardized conditions) and natural exposure (i.e. metal concentrations in feathers of wild urban pigeons), and melanic feather colouration in response to experimental lead and zinc exposure. Both studies (i.e. experimental and correlative) consistently showed that lead exposure decreased iridescent neck feather brightness independently of colour morph. Moreover, lead,...

痕量金属（trace metals）是当前备受学界关注的一类化学污染物，因其与多种人类疾病存在关联，且对野生生物具有毒害作用。既往研究已证实，痕量金属对鸟类的身体状况、免疫功能与繁殖成功率兼具负面（如铅、镉）与正面（如锌）影响。鉴于其对鸟类身体状况的影响，痕量金属或可影响依赖于身体状况的羽色生成——这类羽色可用于配偶选择。本研究以野生原鸽（Columba livia）为对象，探究了铅与锌的实验暴露（即标准化条件下的金属添加处理）与自然暴露（即野生城市鸽羽毛中的金属浓度水平）对其虹彩羽色的影响，以及实验性铅、锌暴露对其黑色素羽色的影响。两项研究（即实验性研究与相关性研究）均一致表明，铅暴露会降低鸽类颈部虹彩羽毛的亮度，且该效应不受羽色型的影响。此外，铅……