Olfactory Behavior: Making Scents of a Changing World

The olfactory sensory system is a part of the nervous system that has something for everyone; with as many as 1,000 genes coding for olfactory receptors it sports the largest gene family in the vertebrate genome; the olfactory sensory neurons regenerate throughout life; the sensory neurons send axons directly into the nervous system with the first synaptic contact occurring within the olfactory bulb; and it is the functional unit for essential behaviors such as courtship, predator avoidance and localization of food sources. Olfactory behaviors are unique in that the sensory coding of the system is not understood in as much detail as other sensory systems such as the visual and auditory systems, and the central projections are processed differently within the central nervous system. Here I review aspects of olfactory behaviors in fish, with an emphasis on zebrafish, and ponder the future of olfactory behavior research in the coming decade.