Learning is a fundamental source of individuality.

Learning significantly enhances behavioral individuality in genetically identical Drosophila, with persistent effects observed across 90 genetic backgrounds.

• Why it matters: Understanding the sources of behavioral variation is crucial for deciphering how individuality arises beyond genetics and environment, impacting fields from neuroscience to evolution.
• What they did: The study measured behavior in thousands of flies performing tasks with or without learning requirements, and used computer simulations to replicate the phenomenon, highlighting reinforced learning's role.
• The result: Learning-induced individuality persisted over time and was amplified by initial condition differences, demonstrating that momentary experience extends genetic and environmental influences on behavior.