Global urbanization processes have highlighted the importance of understanding the effects of urban habitats on animal behavior. Behavioral changes are usually evaluated along an urbanization gradient, comparing urban and rural populations. However, this metric fails to consider heterogeneity between urban habitats that can differ significantly in their characteristics, such as their level of environmental variability. We suggest incorporating dimensions of environmental variability into the urbanization metric. We tested the importance of both level of urbanization and level of urban stability (the rate of anthropogenic changes) on animals' behavioral flexibility by comparing reversal learning abilities in house sparrows from sites differing in the rate of urban development over time. We show that at least for males, urban stability better explains levels of behavioral flexibility than urbanization level. We further show that urban stability corresponds to other behavioral traits such as scrounging behavior and foraging activity. Thus, considering environmental stability and predictability in the form of urban changes can help better understand the mechanisms allowing behavioral changes and adaptations to urban environments. Evaluating the dynamics of the urban built environment could provide a better metric with which to understand urbanization effects on wildlife behavior and an important next step in urban ecology.

Reversal learning experiment results for all 65 house sparrows.

Supplementary figures and tables.