The Sea Inside

is light beyond light, just as it shades into utter darkness – the profundity where they spend most of their time.
    It’s as if we were walking around with the night forever over us
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as indeed we are, since the blackness of space is always there. The black and the blue, the dark and the light only underline the sense of scale. The whale’s environment would mean death for me. But it represents life in such a vast dimension that it takes all the fear away. I might be hypnotised by these mysterious animals, persuaded to stay a little longer, just to see what happens. Like the urge to throw myself off a cliff, the depths and their whales both appal and attract, dangerously. They have the measure of me.

    Out of the obscurity, a dark shape resolves itself into a large whale, a female. From below, it is joined by its calf. As they move just beneath the surface, the young whale aims at its mother’s belly to feed.
    It is an intimate tableau, and I feel like an interloper, as if I were staring at a woman breast-feeding in a café. Animals as old as thirteen have been found with milk in their stomachs, the equivalent of a human teenager suckling at their mother’s breast, or indeed the breast of their aunt or their mother’s best friend. This is alloparental care – a shared responsibility in which even unrelated females will suckle one another’s young while their mothers dive for food, as much for comfort and succour as for sustenance. These babysitters include non-reproductive or elderly females; whale tribes have a role for members which might otherwise be regarded as useless.
    Such behaviour emphasises the obvious: that sperm whales live in highly developed social structures. ‘Sperm whales are nomads, almost continuously on the move,’ says Hal Whitehead. ‘Their most stable reference points are each other.’ Home to a whale is other whales. Strong social bonds define sperm whales, like elephants, which they much resemble – the one possessed of the biggest brain on land, the other in the sea; both using over-developed noses as an extension of their senses; both with ivory teeth or tusks and small knowing eyes set in wrinkled grey skin; both highly matriarchal
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sperm whales might as well be elephants in the water, or elephants, whales on legs. And as elephant society is itinerant, centred around itself, so where whales are not is as important as why they are there
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both to themselves, and to scientists. Hal estimates a post-hunting global population of 360,000 sperm whales spread over 316,620,000 square kilometres of ocean, ‘giving a mean average density of 0.0011 whales/km 2 ’. Such sums cannot assess how many whales lived in the oceans before that, although, before the global spread of
Homo sapiens
over the past two millennia, sperm whales accounted for the greatest biomass of any mammal on the planet. These ancient animals might as well be updated dinosaurs, facing the same prospect of extinction.
    By the time I was born, most of the world’s great whales had been killed. Twentieth-century whaling devastated cetacean societies by depriving them of large males, a legacy which, given the longevity of whales, may take centuries to work out. That they manage to thrive, above and beyond all the threats they still face, is proof of the power of their natural selection and their social organisation. Given that their culture and organisation is passed on matrilineally, it is intriguing to wonder why sperm whales are so focused on the female line. One explanation is that, unlike land mammals, such groups cannot rely on males to defend them, since they may be attacked from any direction, in their three-dimensional world; and in any case, bull sperm whales travel far from the females, to remote northern or southern latitudes, in the same way that male elephants wander, returning only to breed. Thus the masculine role is reduced, and social hegemony reversed; perhaps sperm whales are truly liberated.
    At the same time, however – and somewhat paradoxically
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Hal and his colleagues observe that these huge clans are mostly restricted to the Pacific, perhaps for reasons of safety, since the possibility of attack from orca is greater there than in the Atlantic. The result is a social difference between the whales of these two oceans similar to that between Western and Asian humans; they are all the same species, but subject to very different cultures.
    In his attempt to make sense of these shifting,