Zhang Jinggang, Santema Peter, Li Jianqiang, Deng Wenhong, Kempenaers Bart
Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, China; Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany.
Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany; Edward Grey Institute, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
Curr Biol. 2023 Mar 27;33(6):1125-1129.e3. doi: 10.1016/j.cub.2023.01.047. Epub 2023 Feb 17.
Urbanization is transforming ecosystems at a global scale and at an increasing rate, and its profound consequences for wildlife have been well documented. Understanding how animals thrive in the urban environment and how this environment affects (co-)evolutionary processes remains an important challenge. Urban environments can provide resources such as food or nest sites (e.g., cavities) and also reduce exposure to predators. For some species, urban environments may also affect susceptibility to brood parasitism, 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.
城市化正在全球范围内以越来越快的速度改变生态系统，其对野生动物产生的深远影响已有充分记载。了解动物如何在城市环境中繁衍生息以及这种环境如何影响（共同）进化过程仍然是一项重大挑战。城市环境可以提供食物或巢穴（如树洞）等资源，还能减少被捕食的风险。对一些物种来说，城市环境可能也会影响其对巢寄生的易感性，但这从未经过实验验证。在此，我们结合野外观察和实验操作，发现作为杜鹃（大杜鹃）常见宿主的白眉歌鸫会在靠近人类的地方筑巢以避免巢寄生。首先，白眉歌鸫距离最近建筑物越远，被寄生的可能性越大。其次，白眉歌鸫会根据巢寄生风险的季节性可预测变化来调整筑巢位置。第三，在杜鹃自然不存在的时期通过实验模拟其出现，增加了白眉歌鸫在室内筑巢或在更靠近人类住区处筑巢的可能性。这些发现表明，白眉歌鸫会主动选择在人类住所附近筑巢以抵御杜鹃。我们的研究例证了动物如何利用城市环境，将其作为抵御有害种间相互作用的新防线。
