Mushroom bodies (MBs) are bilaterally symmetrical, fly brain structures required for olfactory learning and memory. Each one is derived from four neuroblasts and consists of ∼2000 Kenyon cells (KCs) that project dendrites into the calyx where olfactory inputs are received and processed. Zhu et al. have used a clonal system to visualize neurons in whole-mount brain preparations to address key questions about the organization of these dendrites, such as: do KC dendrites of different clonal origin occupy the same or different territories in the larval and adult calyx? Their results on shed light on these important questions. For example, they find that MB dendrites of different clonal origins, although well mixed in larval brains, become restricted to distinct calycal spaces in adults, and that various subtypes of MB dendrites contribute differentially to calycal regions.
