From the rainforest to the concrete jungle: On the causes and consequences of altered sexual communication in urban túngara frogs

Túngara frogs are common in both natural and urban areas and are therefore an interesting species to study how evolution is affected by urbanization. In this dissertation I investigated the causes and consequences of differences in sexual communication between urban and forest frogs. Light and noise pollution have direct effects on the communication and hormone balance of frogs, and lead to more conspicuous calling behavior. In the city there are fewer predators that prey on calling frogs, so more conspicuous calling behavior in the city has a low risk and can therefore be seen as an adaptation. In addition, I found heritable differences between urban and forest frogs, meaning that these differences could evolve further over several generations. Finally, I showed that light and noise pollution influence interactions between rivals and mate choice and therefore impact fitness, but in a different way for urban and forest frogs. Taken together, it appears that there is potential for evolution of sexual communication in túngara frogs, which could help this species further adapt to urban areas in the long term.