Much is unknown about humpback whale (Megaptera novaeangliae) song. The behaviour is limited almost exclusively to
males, occurs almost exclusively on the calving grounds and is identical within a population, although it changes periodically
throughout the season. Much of current thinking associates humpback whale song with breeding, although it is not clear if it is
intended to attract a mate, fend off challengers, or a combination of the two. There is, however, very little information on the
internal biology of these large, sea-going mammals, so the majority of hypotheses have not considered much in the way of
physiological mechanisms. Nonetheless, we believe that there is enough information available to infer that a seasonal
process of neurological development and atrophy similar to that found in other animals may be present in humpback
whales. We believe this explains why humpback whale song is not produced between breeding seasons and also why it
does not vary between seasons, while it does so within a season. It also adds additional weight to the idea that humpback
whale song is an honest signal of fitness to a potential mate or competitor.