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A recent study (Bentley et al. 2004) presented evidence for the presence of an immunoreactive third GnRH in songbirds that is clearly hypophysiotropic and has gonadotropin-releasing capabilities. This third GnRH, immunoreactive (ir)-lamprey GnRH-III, possibly has multiple functions, as suggested by its widespread distribution. In addition, ir-lamprey GnRH-III is present in abundance in telencephalic areas, including the hippocampal formation and the song control system. In no vertebrate has a GnRH been localized in these “higher” control regions before, although fragments of mammalian GnRH have been detected in primate forebrain, and their functions are unknown (Terasawa et al. 2001). In fact, we are aware of only two studies that have investigated the GnRH system concurrently with the oscine song control system (MacDougall-Shackleton et al. 2001; Marsh et al. 2002), most likely because the distribution of ir-chicken GnRH-I and -II are so distant from telencephalic areas (Juss et al. 1992; Millam et al. 1993). The finding that a third GnRH is likely involved in regulation of reproductive function in songbird species has implications for the way in which we envisage the avian brain processes environmental cues and transduces them into endocrine signals. We will understand this putative peptide more when it is isolated and sequenced from the songbird brain.