Leviathan. Philip Hoare

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СКАЧАТЬ companions will remain around her to the last moment, or until they are wounded themselves’. This was known as ‘heaving-to’ by whalers, who capitalized on their prey’s fatal tendency to foregather when endangered, and destroyed entire schools ‘by dextrous management’. ‘They did not swim away or dive,’ wrote an observer of a twentieth-century hunt. ‘The gunner, therefore, took the whales very easily, starting with the largest one.’ As Beale adds, poignantly, ‘The attachment appears to be reciprocal on the part of the young whales, which have been seen about the ship for hours after their parents have been killed.’

      To humanize the whale oversteps boundaries; but when entire families follow a stricken relative to strand on a beach, or when a wounded female, mortally gashed by a ship’s propeller, is borne up by the shoulders of her fellow whales, it is difficult to resist the pang of emotion. They are truly gentle giants: as elephants are supposed to bolt at the sight of a mouse, so sperm whales can be faced down by a pod of militant dolphin. The appearance of a seal, or even the click of a camera, may send them scurrying. It is almost as though, as Dr Whitehead remarks, the whale sees its own habitat as a dangerous, even frightening place.

      Yet these are carnivorous animals, voracious in their appetites. They eat mostly cephalopods, but also take tuna and barracuda; entire thirty-foot sharks have been found in their bellies. And they consume in enormous proportions, taking from three to seven hundred squid a day: worldwide, sperm whales eat one hundred million metric tons of fish a year–as much as the annual catch of the entire human marine fishery.

      Diving deeper than any other mammal, we simply do not know how sperm whales behave in the ocean’s depths. We know what they eat, because we find it in their stomachs; but we don’t know how it gets there. Sound is certainly important to their sustenance. Although they lack a voice box–as Thomas Beale noted, ‘The sperm whale is one of the most noiseless of marine animals…it is well known among the most experienced whalers, that they never produce any nasal or vocal sounds whatever, except a trifling hissing at the time of the expiation of the spout’–the whale possesses the largest sound system of any animal, using one-third of its body to create the loud clicks that it constantly emits when hunting. The whale’s oversized nose is in fact a huge and highly efficient squid-finder.

      As bats send out sonar to find flying insects, so sperm whales send out similar, if rather louder, pulses to locate their prey. Their characteristic clicks are produced by the expansion and contraction of ‘blisters’ on their nasal sacs. It is a remarkably complicated sequence, as Dr Whitehead explains. Two nasal passages run from the external blowhole, the left and the right. The left runs directly to the lungs, but the right passes through a distal air sac via a kind of valve known as the museau du singe, or ‘monkey’s muzzle’.

      Sound is initially generated by air being forced through this valve–not unlike the clicks you can make by hitting the roof of your mouth with your tongue–then passes through the animal’s upper spermaceti organ or ‘case’ before bouncing off another, frontal air sac set at the back of the skull–a bony sound mirror, in effect. This is then redirected and broadcast through a series of acoustic lenses in the ‘junk’, the lower oil-containing organ in the whale’s head. Thus the strange mechanism of the sperm whale’s nose acts as a living amplifier. Some sound also bounces back and forth along the case, producing a second pulse. As this inter-pulse interval is equal to the length of the case, the actual sound created by the whale–the pulses between its clicks–may be a measurement of its physical size; one may tell the length of the animal from the inter-pulse interval, just as the bigger the whale and its head, the more powerful its clicks. Breeding males may size each other up from their clicks, and can tell each other’s sex by the same sound; they are as much a tribal definer as the click speech of the Xhosa of South Africa.

      The clicks, which can be heard for many miles, are important for navigation and communication. They extend the whale’s sensory map far beyond its own body, and their speed and variation change from group to group, as an English dialect changes from Yorkshire to Hampshire. This allows individual whales to identify and communicate with members of their family, evenas they use the earth’s magnetic fields to map out their subaquatic terrain, the peaks and valleys of the oceanic abyss in which they are effortlessly at home. And as they dive–often in an informal group–they use their clicks to locate and scan, with extraordinary precision, the distance, presence and nature of their prey. It is thought that a whale can ‘see’ into its prey, diagnosing it–even to the extent that it can tell if it is pregnant. The returning clicks are ‘heard’ through the dense, hard jaw bone–the same bone from which Ahab’s false leg is carved–and which acts as a listening device in its own right, conducting sound through bioacoustical oils directly to its eardrums. The whale’s external ear is largely useless; the animal hears through its body itself.

      The deeper it dives, the more effective the whale’s senses are, away from the chatter and interference of the world above. A sperm whale can create a two-hundred-decibel boom able to travel one hundred miles along the ‘sofar’ channel, a layer of deep water that readily conducts noise. It seems strange that such a physically enormous creature should rely on something so intangible; but bull sperm whales, by virtue of their larger heads, generate sounds so powerful that they may stun or even kill their prey. These directional acoustic bursts, focused through their foreheads and likened to gunshots, are the equivalent, as one writer notes, of the whale killing its quarry by shouting very loudly at it.

      In their own researches, Soviet scientists, whose nation’s enthusiastic hunting of the sperm whale in the twentieth century allowed ample opportunity for such study, suggested that in order to hunt in the depths where only one per cent of sunlight penetrates below two hundred metres, the whale uses a ‘unique video-receptor system…which lets the animal obtain the image of objects in the acoustic flow of reflected energy even in complete darkness’. In other words, the sperm whale can see its prey in sound. And just when you think nothing else about this animal could confound you, another theory proposes that the whale’s sonic bursts, and the movement of its head, may cause plankton in the deep water to emit their bioluminescence. In the utter darkness, the leviathan may light its own way to its lunch.

      Even as you leave the Tube station, you remain an underground passenger, conducted through a tiled tunnel before emerging into the shadow of an extravagant cathedral of science. Clinging to the terracotta façade–itself layered to resemble geological strata–is an industrial bestiary: heraldic griffins and scaly medieval fish and, most frightening of all, grinning, toothy pterodactyls, with their obscene storks’ beaks and glaring gargoyle eyes and their leathery wings wrapped about them.

      In the gothic nave, children mill about a blackened diplodocus nonchalantly waving its whiplash tail. A hundred years ago, they would have been greeted by another monster, for here stood the skeleton of a sperm whale, guarded by what appeared to be a Victorian policeman as if it were a prisoner at Pentonville.

      The route comes back like a lost memory. I walk past ichthyosaurs sailing through long-vanished Triassic seas and moth-eaten fauna of the savannah and the jungle, displays out of a dead zoo. Abruptly, the corridor turns into a space more like an aircraft hangar than a museum. There, hanging like one of the model aeroplanes I used to suspend from my bedroom ceiling, is the blue whale, the largest object in the Natural History Museum.

      Contrary to the usual tricks of childhood recollection, it is actually bigger than I remember. Nearly one hundred feet long from the tip of its nose to its twenty-foot flukes, the whale could easily accommodate a large household within its interior. There is something fairy-tale about it, an invention of the Brothers Grimm: its huge mouth has a faint grin, and its disproportionately small eye stares out from its wrinkled socket, part amused, part pleading. Even Linnæus’s name for it is a little Swedish joke: Balænoptera musculus–Balæna meaning whale, pteron, wing or fin, and musculus, both muscular, and mouse.

      I was fooled by this model then, as visitors are now, for this wood and plaster reconstruction is only an approximation СКАЧАТЬ