We (read: allround-talented PhD student Gabriel Munar Delgado) program transponder-operated automatic feeders to provide access to individual sparrows only in specific parts of the study area. Does having access to a novel resource change where sparrows breed, and with whom they end up breeding? Basically, we test if performance-dependent habitat choice by individuals can cause adaptive population divergence, as an alternative to divergent natural selection. (PhD project codirected by Francisco Pulido)