Song sparrows living in urban habitats show different patterns of neural activity after hearing a competitor's song (as captured by immediate early gene expression), than those living in rural habitats. These differences were found in two regions of the 'social behavior network' of brain, which, as the name indicates, regulates social behavior. Additionally, urban and rural birds have different amounts of a neural chemical, arginine vasotocin (AVT), in a brain region specifically implicated in regulating aggression (BSTm). Though much more work needs to be done, these findings published in a special edition of Frontiers in Ecology and Evolution suggest that the social behavior network is involved in behavioral adjustments that song sparrows make to urbanization. For more information check out the full article!