Sex-specific food-preference decisions are influenced by modulated sensory function. A. Humans exhibit sex differences in preference for salt, and salt preference in women changes over the menstrual cycle. The mechanisms underlying these different food preferences are unknown (reprinted with permission from . Copyright 1994, Elsevier Ltd.). B. Female fiddler crabs exhibit greater behavioral sensitivity to food stimuli. Sex differences in physiological responses of sensory neurons to food-related stimuli in crabs mirror differences in behavior (reprinted with permission from . Copyright 1995, Springer-Verlag) C. Serotonin is known to regulate carbohydrate consumption in several species. Treating Drosophila females with the precursor for serotonin elevates the level of this neurotransmitter, and mimics food-preference changes that occur as a function of reproductive status (Reprinted with permission from . Copyright 2010, Elsevier Ltd.).