Of Whales and Teeth by Louis Arth ur Norton
[CaptainAhab} ... saw a white living spot no bigger than a white weasel, with wonderful celerity uprising, and magnifying as it rose, till it turned, and then there were plainly revealed two long crooked rows of white, glistening teeth, floating up from the undiscoverable bottom. It was Moby Dick's open mouth and scrolledjaw; his vast, shadowed bulk still half blending with the blue ofthe sea. -Moby-Dick, "The Chase, First Day"
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hales, dolphins, and porpoises (cetaceans) are divided into two large groups (suborders)-baleen and toothed. The larges t group, containing the largest whales, is the baleen whales: blue, fin, right or bowhead, humpback, and minke whales, among others. These animals have flat flexible plates with frayed edges arrayed in parallel rows, sieve-like structures composed of comb-like thick hairs made of keratin (a common biological substance similar to fingernail material) . 1hey erupt to form upper jaw filtration curtains used to strain plankton from seawater. The
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appendage can approach six meters in length. Embedded in this mandible are two rows of broad, conical, and slightly recurved teeth angled towards the gullet. And now behold Jonah taken up as an anchor and dropped into the sea; when instantly an oily calmness floats out from the eas t, and the sea is still, as Jonah carries down the gale with him , leaving smooth water behind. He goes down in the whirling heart of such a masterless commotion that he scarce heeds the moment when he drops seething inro the yawning jaws awaiting him; and the whale shoots-ro all his ivo ry teeth, like so many white bolts, upon his prison. Then Jonah prayed unto the Lord out of the fi sh 's belly. -Moby-Dick, "The Sermon" Melville's m etaphoric "white bolts" are firmly attached to, and largely covered by, the fibrous dense gum tissue (gingiva) with on ly the tips of the teeth exposed to the elem ents. After a whale was killed and its lower jaw hoisted on board a whale ship, the teeth were usually stripped off as a unit like peas embedded in an opened gingival pod; the minimal underlying bone indicates a weak WHALE TE ETH FROM TH E COLLECT IO N AT T H E NEW BED FORD WHALING MUSEUM, PHOTOS BY LOU IS A. NO RTON
largest toothed whale is the sperm whale (Physeter catodon), with a head occupying one-third of its entire body. Its teeth are usually broad, but many are narrow and pointed to catch squid. In the case of orcas, the teeth are very pointed to catch fish and other prey, such as sea mammals and sea birds. The mouth or "m aw" of the sperm whale has been the source of legend and at times terror as depicted in Melville's Moby-Dick by way of the opening lines of Father Mapple's sermon: The ribs and terrors in the whale, Arched over me a dismal gloom, Whi le all God's sun-lit waves rolled by, And lift me deepening down to doom. I saw the opening maw of hell, With endless pains and sorrows there; Which none but they that feel can tell Oh, I was plunging to despair. The sperm whale's mouth has a long and slender lower jaw or mandible, consisting of two halves that are wide at the joint surfaces (condyles), where it articulates with the base of the skull and fused anteriorly to form an elongated chin or symphysis. This
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1his row of sperm whale teeth, approximately 12 cm long, are still attached to a highly desiccated gingival tissue. periodontal ligament. The two rows of short conical mandibular teeth are well separated mesially and distally (fore and aft) . Th e surface of the raw tooth has thin narrow grooves or striations from the crown descending to its root. The tooth's single root is embedded in a mandibular socket, but not rigidly fixed within the bone as in a gomphosis. Instead they are strongly supported in place by the thick fibrous gingival tissue. Their removal is described by Melville as follows:
SEA HISTORY 128, AUTUMN 2009