Daurian redstarts move their nesting sites closer to or even inside human settlements when cuckoos are around. In doing so, they actively protect their nest against brood parasitism, as cuckoos avoid human settlements. An international team of scientists showed both observational and experimental evidence for this anti-parasitism strategy in a population of Daurian redstarts in northeastern China. Their research illustrates how the breeding behavior of two interacting bird species co-evolves. It also gives us a glimpse on how urbanization can affect interspecific interactions.