城市化正在全球范围内以越来越快的速度改变着生态系统,1,2及其对野生动植物的深远影响已得到充分记录。3,4,5,6了解动物如何在城市环境中茁壮成长以及这种环境如何影响(共同)进化过程仍然是一个重要挑战。7城市环境可以提供诸如食物或巢穴等资源(例如,空洞)10,8,9,也减少了对捕食者的暴露。11,12对于某些物种,城市环境也可能影响对寄生的易感性,13,14,但这从未经过实验测试。这里,我们使用现场观察和实验操作的组合来显示Daurianredstarts,腓尼古鲁,普通布谷鸟的共同宿主,Cuculuscanorus,在靠近人类的地方筑巢,以避免育巢寄生。首先,随着与最近建筑物的距离增加,redstarts更有可能被寄生。第二,redstarts调整了它们的筑巢位置,以应对季节性可预测的育巢寄生风险变化。第三,通过实验模拟杜鹃在自然不存在的时期内的存在,增加了redstarts嵌套在室内或更靠近人类住区的可能性。这些发现表明,redstarts积极选择将其巢穴放置在人类住所附近,以防御杜鹃。我们的研究举例说明了动物如何利用城市环境,将其用作抵御有害种间相互作用的新型防线。
Urbanization is transforming ecosystems at a global scale and at an increasing rate,1,2 and its profound consequences for wildlife have been well documented.3,4,5,6 Understanding how animals thrive in the urban environment and how this environment affects (co-)evolutionary processes remains an important challenge.7 Urban environments can provide resources such as food or nest sites (e.g., cavities)10,8,9 and also reduce exposure to predators.11,12 For some species, urban environments may also affect susceptibility to brood parasitism,13,14 but this has never been tested experimentally. Here, we use a combination of field observations and experimental manipulations to show that Daurian redstarts, Phoenicurus auroreus, a common host of the common cuckoo, Cuculus canorus, nest in proximity to humans to avoid brood parasitism. First, redstarts were more likely to be parasitized with increasing distance to the nearest building. Second, redstarts adjusted their nesting location in response to a seasonally predictable change in the risk of brood parasitism. Third, experimentally simulating the presence of cuckoos during a period when they are naturally absent increased the likelihood that redstarts nested indoors or closer to human settlements. These findings suggest that redstarts actively choose to place their nest in the vicinity of a human residence as a defense against cuckoos. Our study exemplifies how animals take advantage of the urban environment by using it as a novel line of defense against detrimental interspecific interactions.