A mother’s physiological response to her environment is an important source of behavioral variation in her offspring. Females in more competitive environments transfer more testosterone to their developing offspring, which can make offspring more behaviorally aggressive. This is potentially beneficial as aggressive behaviors can improve success in competitive interactions, but aggression is also costly. Thus, a mother’s ability to communicate the environment to the next generation, helping them match their behavior to it, can be critical to their success. However, the mechanisms underlying how maternal hormones shape behaviors and the extent to which they are beneficial remain poorly understood. The proposed work will identify gene networks in the hypothalamus, a brain region that regulates hormones and social behaviors, that are sensitive to early testosterone across development and relate them to adult behavior. This work will also test how well early testosterone exposure prepares offspring for competitive environments. While this maternal effect is observed in many species, this work will be performed in the well-studied avian species the house sparrow (Passer domesticus), given the ease of manipulating hormones in externally developing eggs. This research includes integrated educational aims to enhance engagement with science by creating authentic research experiences for students and data science training opportunities. It will also engage the public in animal behavior