Maklakov, a researcher in the Department of Animal Ecology at Uppsala University, and his colleagues studied how well -- or not -- 82 species of passerine birds belonging to 22 avian families did in and around a dozen cities in France and Switzerland.
Bird species that were able to breed in city centers were considered successful colonizers. Birds that bred around the cities, but not in the urban regions themselves, were considered to be urban avoiders.
For the study, which is published in the latest issue of Royal Society Biology Letters, the scientists also looked at the brain size and body mass of each bird.
The researchers determined that the following are brainy birds that do well in cities: the great tit, the blue tit, the carrion crow, the jackdaw, the magpie, the nuthatch, the wren, the long-tailed tit and more. Pigeons are not passerines, so these ubiquitous urban dwellers were not included in the study.
While pigeons are smart, they are not necessarily the Einsteins of the bird world. "Pigeons probably represent a great example of a bird for which we inadvertently created a fantastic replica of their original habitat with plenty of nesting places, near lack of predators, and an ample food supply," Maklakov explained.