A small group of chemically related molecules regulates various neurophysiological processes and behaviors. These so-called biogenic amines were formed very early in evolution. To elucidate their exact function, scientists in the Research Unit “Biogenic Amines in Insects: Coordination of Physiological Processes and Behavior” analyze the relatively simple structures of the nervous systems of different insect species, such as the honeybee, grasshopper, or fruit fly Drosophila. Through its investigations at different system levels of the insect brain, the Research Unit aims to reach a comprehensive understanding of biogenic amines, which should in turn lead to some important conclusions about the function of these molecules in vertebrates.