Humans are rapidly transforming natural ecosystems into urban areas, leading to an alarming loss of biodiversity, in particular in the tropics. Some of this biodiversity loss could be mitigated if species are able to adapt to these evolutionary novel urban environments. An important aspect of urban success concerns adaptation to a sensory environment that is heavily affected by acoustic noise and artificial light pollution. Animals can for instance alter their sexual signals to optimally attract mates in the novel urban habitats. However, such change in sexual traits may at the same time attract more unwanted eavesdroppers, such as predators and parasites.The aim of this proposal is to understand whether and how sexual communication signals can adapt to the urban environment. The first research objective addresses how signal traits can change in response to the altered sensory environment of cities. For this objective we will record the sexual signals of frogs from forest and urban populations and relate various signal traits to variation in the sensory environment, such as anthropogenic noise and light levels. The second research objective addresses how signal change affects both attraction of mates and unwanted eavesdroppers present in urban areas. We will play urban and forest recorded signals in urban and forest environments to test their attractiveness to females as well as predatory bats and parasitic flies.