Urban birds need to be smart or fast-breeding

To thrive in urban environments, birds need to either have large brains, or breed many times over their life, according to a new study involving UCL. The study, published in Frontiers in Ecology and Evolution , suggests that birds have two alternative strategies for coping with the difficulties of humanity's increasingly chaotic cities. "The expansion of cities is a major driver of biodiversity loss and even extinction, and yet some animals are able to thrive in cities. We hope that by identifying which species are better able to adapt, we can also predict which species may be at risk and how to support them with targeted conservation efforts," said co-author Dr Alex Pigot (UCL Centre for Biodiversity & Environment Research). "The species that can tolerate cities are important because they are the ones that most people will have contact with in their daily lives, and they can have important effects on the environment within our cities," he added. The study's lead author, Dr Ferran Sayol (University of Gothenburg and the Gothenburg Global Biodiversity Centre in Sweden) added: "Cities are harsh environments for most species and therefore often support much lower biodiversity than natural environments." Past studies have shown that birds with larger brains have a number of advantages, such as being better able to find new food sources and to avoid human-made hazards. But researchers haven't yet been able to explain why some species with small brains - such as pigeons and swifts - also are able to flourish in cities.