Humpback Vocalizations

Abstract

Humpback Vocalizations Rajiv Mohabir (bio) Rajiv Mohabir, poem, humpback, whales, Hal Whitehead, Luke Rendell, whale song In any birthing area, humpbacks sing the same, slowly evolving song. Learning strains from one another, they sing across the fathoms, their phrases and themes shifting in a pattern of small changes until they stitch new songs of older material. Songs at the end of the summer transform from the beginning of the season. Biologists Hal Whitehead and Luke Rendell write that, in Hawaiian waters, groups of the North Pacific variety alter their own songs in response to songs they have heard from other, very distant, humpbacks. This suggests music carries across thousands of miles. When apart the songs of different socializing groups evolve at similar rates. Or at some meeting place mid-migration do humpbacks gather? ________ Mysticetes do not have phonic lips or a museau de singe as with whales like odontocetes Larynges large as British call boxes emit frequencies Megaptera novaeangliae's U- folds between upper and lower respiratory systems vibrate [End Page 93] ________ To hear sound and song and noise alike, scientists must dig further into the biology of a humpback's curved bulla. They know it attaches to the cetacean's jaw. The bulla looks like a conch shell or a giant clam that's been warped into a cave. Or it looks like a sliced mushroom or the mouth of a cowrie shell, but delicate. For sound to be realized in the tympanic plate, fat and soft tissue must vibrate against the jaw. The cochlea joins to the periotic by a thin membranelike bone. This formation, the tympanoperiotic complex, processes soundthrough bone conduction. ________ No one knows the why or where of it, but most agree whale song is moving. Why else send recordings in the Voyager spacecraft on the Golden Record? Is it the slow erasure of a species that wails out? Humans look for meaning and aesthetics in what they cannot understand— Biologists Whitehead and Rendell wonder why whale song rhymes or is perceived as rhyming through pattern repetition. Is it lyrical? Is it cetacean rhetoric? How human language breaks apart at the point of conception. The echo is amniotic. We, once aquatic, heard as whales do. ________ Megaptera novaeangliae's tympanoperiotic complex is designed to hear songs across great distances at frequencies below what the human ear can discern. It is a delicate instrument of song and divination, an environment under threat of shipping lanes [End Page 94] and naval sonar pulses. Songs are made of notes, or base units that humpbacks emit at 30–4,000 hertz, which is in the range of human hearing. Acoustic trauma will rupture the process— whales no longer able to tell how deep they dive. The pressure crushes— ________ In representations of the structure of humpback vocalizations, bioacousticians chart the anatomy of the line. Repetition, irregularity, looseness, and deft shifts of breath and phrase magic the water column. aaa bcb cbc ded eff ded eff g The rhyme sense in a complete song leaves the listener in a sonically unfamiliar place. In fact, the g cascades, a grand departure—a kind of poetic anticlosure asking for riff and response. Perhaps this is an eight-stanza poem, mediated through human interpretation of what we can only imagine, not living in a three-dimensional water column. ________ O O O O O O O O O O O O O O O O ________ OAccording to cetacean biologists, a unit may be imagined tO be nOtes of humpback song.| | | O | O | O | A collection of units is called a phrase (Of up tO ten seconds). Modulated O frequency O| | O | | | | and amplitude, the nOtes are wrOught into phrases humpbacks repeat into a theme. Whales,| O O O | | | | | which scientists postulate sing for aesthetics' sake (hence poetry), add theme to theme, they| | | | | | weave songs that last for up to twenty to thirty minutes each. Some, they repeat for days. [End Page 95] ________ Whale song constantly evolves though the extinction event looms—That great god. Whales in the same regions sing similar, if not the same, songs during the same times, each whale shifting tune and phrasing to...