identified four species: Physeter macrocephalus, P. catodon, P. microps and P. tursio, but all are now known as one, with the pygmy and dwarf sperms–Kogia breviceps and K. sima–recognized as a separate family, Kogiidæ.) Relics of prehistory, they are, in one scientist’s words, ‘victims of geologic time…held in the rubbery bindings of [their] own gigantic skin’. Their nearest relation on land is the hippopotamus, although with their grey wrinkledness, small eyes and ivory teeth, they remind me more of elephants.
The sperm whale remains a class apart. Its shape itself seems somehow unformed, inchoate, as though something were missing–a pair of flippers or a fin. It is an unlikely outline for any animal, still less for the world’s largest predator. To Ishmael, the whale was the ominous embodiment of ‘half-formed fœtal suggestions of supernatural agencies’. Now it is seen as a ‘generally benign and vulnerable creature’; from a fearful foe it has become a placid, gentle giant of the seas. The distance between these two notions is the distance between myth and reality, between legend and science, between human history and natural history. It is a mark of its magical nature–and a symbol of the fate of all cetaceans–that the sperm whale has achieved such a transformation, from wilful dæmon to fragile survivor.
Physeter macrocephalus may have been around for millennia, but we have really only known it for two hundred years; only with the advent of modern whaling, at the beginning of the eighteenth century, did man come to comprehend even an inkling of the animal. It continues to confound us. The sperm whale is a greater carnivore than any dinosaur–a fact that threatens to turn its fearsome jaws into those of an aquatic tyrannosaur–although its body is ninety-seven per cent water, just as humans are mostly made of the same liquid; we all contain oceans within us. Like other whales, the sperm whale never drinks. It has been described as a desert animal; like a camel living off its hump, its thick layer of blubber allows the whale to weather the vicissitudes of the ocean, from feast to famine. In an environment in which food stocks alter drastically, there is an advantage in being able to live for three months without having to eat, and to be able to range over huge distances in temperatures ranging from tropical to Arctic.
Truly, these are global animals. Sperm whales live in every latitude and every ocean, from the North Atlantic to the South Pacific, even in the Mediterranean. Visual surveys from planes and ships have calculated that 360,000 of them still swim the world’s seas, although that is barely a quarter of the population that flourished before the age of the iron harpoon. Their love of deep water, foraging off steep continental shelves, meant that until recently only whalers–who described their quarry as travelling in veins, as if guided ‘by some infallible instinct’ (‘say, rather, secret intelligence from the Deity’, adds Ishmael)–saw sperm whales alive. As a result their study is still in embryo. It is as though we have hardly advanced since nineteenth-century illustrators depicted overweight whales lying on palm-fringed tropical beaches.
What facts we do know cluster together like the whales themselves, defying interpretation. What colour are they? Underwater, they appear ghostly grey filtered through the ocean’s blue, but in sunlight they appear brown or even sleekly black, depending on their age and sex. They may even verge on a dandified purple or lavender, with pale freckles scattered on their underbellies, leading to the pearly whiteness of the ‘beautiful and chaste looking mouth! from floor to ceiling lined, or rather papered with a glistening white membrane, glossy as bridal satins’. From the side and below, this whiteness glows like a half-open fridge; an invitation, and a warning. The huge head is patchy and mottled where the tissue-thin skin is constantly peeling like old paint; it is relatively smooth, but behind, the rest of the body is furrowed and creased like a prune. This mutability gives the animal a metamorphic dimension.
From a hydrodynamic point of view, the sperm whale looks as though it were designed by an eccentric engineer. There are no concessions in its shape. Its sharp-angled flukes are not those of the sinuous and feminine humpback. It is a blunt blunderbuss of an animal; abrupt, no-nonsense. Its squareness appears to confront the water, to defy, rather than comply with the sea. Yet seen from above, its block-like head is quite narrow, wedge-shaped: this is an animal built to spend most of its life in the depths, so much so that one scientist considers it more apt to call the sperm whale a surfacer rather than a diver. Its very size allows the whale to spend long periods of time in the depths, its body being one huge oxygen tank.
Slung beneath its signature snout is the sperm whale’s other most formidable feature: its lower jaw, studded with forty or more teeth which fit into its toothless upper mandible like pins in an electrical socket. These ivory canines range in size from hen’s egg to massive foot-long cones too broad for me to encircle in my fingers. Sliced in half, a tooth can reveal its owner’s age by counting the layers of growth like the annular rings in a tree. In the most elderly whales, the teeth are ‘much worn down, but undecayed; nor filled after our artificial fashion’, Ishmael observes, although, in truth, sperm whales often suffer caries. In rare instances, they also possess unerupted upper teeth, relics of ancestors who boasted a full dentition. Natural selection has left their descendants with only a lower row, as if they had misplaced their dentures during the night. That fact makes the sperm whale seem more benign; only half a monster.
The teeth are yellowy in colour; only when polished do they acquire their bright creamy whiteness, like the little ivory tusks in the carved ebony elephants my grandfather brought back from India after the First World War. Heavy in the hand, they are tactile, smooth, weighty with their benthic provenance. For all their prominence, their function is oddly obscure. One nineteenth-century writer observed that the teeth were marked with oblique scratches, ‘as though made with a coarse rasp’, the result, he thought, of ‘corals, crushed shells, or sand’ and frequent contact with the ocean floor. However, food found in the bellies of sperm whales seldom shows any tooth marks. Juveniles are eating squid and fish long before they develop teeth, and females do not produce any until late in maturity, if at all. Evidently, teeth are not necessary for sustenance. (In some cetaceans they are a positive hindrance: strap-toothed beaked whales, Mesoplodon layardi, have tusks which gradually grow over their jaws, creating a muzzle through which they still manage to feed.)
In his Natural History of the Sperm Whale, published in 1839, Thomas Beale noted that three hunted whales, one of which was blind, and the other two with deformed jaws, were in otherwise good condition, proving that not only did they not need their teeth to feed, they had no need of eyesight, either. This great predator does not chew its prey; rather, it sucks it in like a giant vacuum cleaner, as the presence of ventral pleats on its throat indicates. Some commentators have proposed that sperm whales use their jaws as giant lures, dangling them like an angler’s rod and baited with bioluminescence from previous meals of squid. Beale believed that the whale hung passively in the water, waiting for its food, while squid ‘actually throng around the mouth and throat’, attracted as much by the ‘peculiar and very strong odour of the sperm whale’ as by the ‘white dazzling appearance’ of its jaw. However, modern science has discovered otherwise.
Addressing the conundrum of the sperm whale’s head, Ishmael points out to his otherwise ignorant readers that its true shape is in no way reflected by its skull; no one who saw its bones could ever guess that the living animal possessed such a snout. To him, this is further evidence of deception on a massive scale, and in a phrenological diagnosis–all but feeling the whale’s bumps–he declares that the huge forehead which lends the animal a semblance of wisdom ‘is an entire delusion’. But Ishmael was himself misled, for the sperm whale boasts the biggest brain of any creature ever alive, weighing as much as nineteen pounds (as opposed to the human’s seven). Quite what it does with such an organ is another matter.
Straddling a gallery to itself in New Bedford’s museum is the skeleton of a sperm whale; merely to walk around it is an intimidating experience. The skull alone is more than twenty feet long and stands higher than my shoulders. It is an essentially asymmetrical structure by virtue of its left-leaning blowhole (odontocetes possess single nostrils, whereas mysticetes have two), literally sinister (and I wonder if whales are cack-handed like me). This same quality lends an air of abstract sculpture to the complex construction of caverns and sockets created to accommodate vital vessels and nerves. One opening connects its spinal cord to its brain, another to the ears and eyes, themselves protected by the bony mass