ABSTRACT
Throughout the vertebrates, reproductive hormones are well known to perform two critical functions that synchronize sexual interactions between conspecifics. They act on the brain to induce synchrony between an individual's reproductive behavior and the maturation of its gametes, and they also act on effectors to generate behavioral and other signals that induce reproductive synchrony between conspecifics (Pfaff et al., 2002). In fish, however, hormones can have a third set of actions: after release to the environment, they can serve as sex pheromones. Many sex steroids, prostaglandins and their metabolites are detected with great sensitivity and specificity by a diverse array of fishes, and exert key effects on the reproductive behavior and physiology of such ecologically and economically important taxa as the carps, salmonids, and gobies (Stacey and Sorensen, 2002, 2006).
