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The present experiments were conducted to test the hypothesis that septal arginine vasotocin (AVT) and vasoactive intestinal polypeptide (VIP) modulate directed song (a courtship behaviour) and aggression in male zebra finches (Taeniopygia guttata). Subjects were surgically fitted with a guide cannula directed at the septum. Following recovery they were tested for aggression and directed song following infusions of AVT, its antagonist (anti-vasopressin, AVP), and saline volume control. Infusion of the AVT antagonist significantly reduced all three aggressive behaviours measured (pecks, beak fences and chases); and AVT infusion significantly facilitated beak fencing. Vasoactive intestinal polypeptide treatment significantly reduced pecking. No treatment produced a change in directed song. Comparison with findings in mammals suggests that modulation of aggression by septal AVT (or AVP) is evolutionarily conserved in vertebrates, but modulation of aggression by VIP has not previously been reported for any vertebrate.

The Toll/NF-B pathway is a common, evolutionarily conserved innate immune pathway that modulates the responses of animal cells to microbe-associated molecular patterns (MAMPs). Because MAMPs have been implicated as critical elements in the signaling of symbiont-induced development, an expressed sequence tag library from the juvenile light organ of Euprymna scolopes was used to identify members of the Toll/NF-B pathway. Full-length transcripts were identified by using 5 and 3 RACE PCR. Seven transcripts critical for MAMP-induced triggering of the Toll/NF-B phosphorylation cascade have been identified, including receptors, signal transducers, and a transcription factor. Further investigations should elucidate the role of the Toll/NF-B pathway in the initiation of the beneficial symbiosis between E. scolopes and Vibrio fischeri.

recruitment. The 1996 year-class was the strongest for over a decade but, at the present high exploitation rate of young cod, few individuals have survived to reach sexual maturity.The combination of this exploitation with the recent changes in North Sea temperature, a low spawning-stock biomass and a stock dominated by young immature individuals, means that fishery managers must take precautionary measures 6 . In order to give the mature stock a chance to rebuild, fishing mortality rates need to be reduced to at least the precautionary levels advised by ICES 1 .