The Syntax(?) of Humpback Whale Song

Humpback songs are widely recognized as the second most complex vocalizations in the animal kingdom. The songs are characterized by patterns of repeating phrases which are themselves made up of repeating sub-phrases, which reveal their nested structure. Considerable work has been devoted towards characterizing this hierarchical structure in information-theoretic terms, and towards situating these structures in the Chomsky hierarchy. I explore these facts through a different lens, arguing for their relevance to biolinguistic theories that take Merge, or recursion, as the “final piece” in the evolution of human language. I assess the extent to which the structures found in humpback song are generable by minimalist-style derivations. Two core structural prerequisites must hold for humpback syntax if it is to attributed to a cognitive operation like Merge: first, binary branching, and second, deep embedding of derivationally equivalent syntactic objects. I argue that both generalizations are indisputably born out by the song data, and that we have good reason to believe that humpback songs are generated by Merge. A third structural issue, that of labelling/headedness, is less easily resolved — of course, the analogous topic in human language syntax is far from settled as well.