Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloida
Conservation status: Not listed, but
populations declining
All that was needed was for one of us to manage to make an endless spiral and time could exist.
Qfwfq in Cosmicomics by Italo Calvino
So the whole world blooms continually
within its true and hidden element,
a sea, a beautiful and lucid sea
through which it pilots, rising without end.
from Bathysphere by Don Paterson
Not many living things leave a beautiful corpse. Among those that do are the ancient oak trees still found in a few pockets of woodland in the British Isles, and the Nautilus, a distant cousin of squid and octopus that lives in tropical waters. In the case of an old oak, the folds and twists in its trunk and boughs continue to express, suspended as in a sculpture, forces that shaped the tree during its five hundred years of life. In the case of the Nautilus, the animal that accreted the shell had a relatively brief existence, typically less than ten years, but what remains – in cross section a logarithmic spiral – manifests perfect symmetry. The oak is like a massive, turbulent musical score; the Nautilus shell is like a chord resolved.
I first saw one of these shells cast up on a sandbar off a small island in Indonesia (many hundreds of miles from where, years later, I saw Leatherbacks), a place so quiet and untouched that it was possible to believe one had awoken in an age before – or after – humans. (This was, of course, an illusion: the island was inside a conservation zone policed to exclude masses of hungry people just over its borders.) The shell was broken, but even so it stood out to my eyes almost as if it were a three-dimensional object in a flat world. I felt a surge of wonder – a childish sense that it was a sign from the deep.
The Nautilus shell that I saw was, of course, no token from the gods: no trace on the Rhodian shore. But a closer look at the animal of which it was once part does cast light on real and enduring wonders. This chapter explores three of them. The first concerns time: an individual Nautilus has a short lifespan but the spiral form its shell creates is much older than that of an oak or any other tree, and forms from which it evolved helped in the discovery of the age of time itself.
Greek and Roman philosophers believed that seashells turned to stone and embedded in rocks were the remains of ancient creatures deposited on the floor of a sea that had once covered the land. This idea was all but lost in Europe with the collapse of Roman civilization, and by the time of the Renaissance, when Christian doctrine held that the world was only a few thousand years old, there were two main theories to explain these shells. One claimed that they were non-living structures that had grown spontaneously, like crystals, within the rock. (The fact that they mimicked living creatures wasn’t considered too strange: it was simply thought to reflect the harmony that existed between the various realms of nature.) The other theory claimed that the shells were the remains of sea creatures that had been deposited on mountaintops during the great flood described in the Bible. A few people questioned both ideas, but discreetly. In one of his secret notebooks, written in the early sixteenth century, Leonardo da Vinci observed that fossils were generally found in several superposed layers which looked as if they had been deposited at different times. A single flood could not, therefore, account for them all. He also queried the idea that stony shells grew from ‘seeds’ within rocks because they would not be able to expand, as the growth bands on their shells showed they had, without fracturing the material surrounding them.
More than 150 years after Leonardo, Robert Hooke (sometimes known as the ‘English Leonardo’) had similar doubts when he examined a variety of spiral shapes that were abundant in some rock formations. Hooke believed that these forms, known as ammonites, were the mineralized shells of marine organisms. But he was puzzled because, in contradiction to the Christian doctrine that animals were eternal and unchanging, these ones bore little resemblance to most known shells. Hooke sought out every conceivable living analogue and lighted on the Nautilus, which in his time was a rarity in Europe. Its shell had a similar spiralling shape to that of many ammonites but whereas ammonite shells were mostly corrugated or even covered in spikes, the Nautilus shell was smooth. Hooke’s conclusion was simple and, for its time, daring: ‘there have been many other Species of Creatures in former Ages, of which we can find none at present; and ‘tis not unlikely . . . but that there may be divers new kinds now, which have not been from the beginning’. He was directly challenging the belief that nothing had become extinct and that no new species had emerged since the first act of Creation.
Robert Hooke’s illustration of fossils, circa 1705.
Hooke’s assertions were a signal of a profound shift in European thinking. Over the following century natural philosophers studying fossils and geology in ever greater detail began to see that there was only one coherent explanation for their discoveries: a huge past from which humanity was completely absent. The revelation of what we now call ‘deep time’ was breathtaking for those who first experienced it, like a swoop into stereoscopic vision for someone who has previously only seen in two dimensions and suddenly finds himself on a high promontory above a chasm. ‘The mind [grew] giddy by looking so far into the abyss of time’, wrote John Playfair, a friend of the geological pioneer James Hutton, in 1788.
Erasmus Darwin, a contemporary of Hutton and the grandfather of Charles, was among those who argued for a very long past that allowed ample time for complex life to have evolved from simple beginnings. As to how exactly evolution worked, however, Erasmus Darwin was vague – his motto was E conchis omnia, or ‘Everything from shells’– and it was left to his grandson to propose natural selection. So while Charles Darwin’s theory was not inspired directly by speculation on the relationship between Nautilus and ammonite, it was made possible by an appreciation of the existence of deep time, and this ultimately rested on the work of Hooke and others who had first wondered about the similarities of the Nautilus to these enigmatic, fossilized spirals.
The Nautilus, it turns out, is not descended from an ammonite but is actually a member of an even older subclass of cephalopods known as nautiloids, which first appear in the fossil record around 490 million years ago. About 2,500 different species have evolved since then, but all of those alive today belong to a handful of species in two genera. Today’s Nautiluses are quite different from other living cephalopods such as cuttlefish, squid and octopuses. Most obviously, they still live in their shells, a practice that other cephalopods abandoned tens of millions of years ago. They also have a much simpler nervous system and brain. (They compensate to some extent for their lack of smarts with muscle: up to ninety tentacles – many more than other cephalopods – arranged into two circles around a horny beak.) Unlike other cephalopods, the tentacles of the Nautilus have no suckers but they are ribbed, and when wrapped around prey – a favourite dish is a lobster that has just shed its old shell, and is soft – they exert a powerful grip until the animal can start to nip into the flesh of its victim. The Nautilus, floating through the water thanks to gas-filled internal chambers, may wobble and bump into things as it pushes itself through the water, but it is a deadly enough hunter of its chosen prey when the opportunity arises, jet-propelling itself at some speed by sucking water into a cavity in its mantel and then expelling it with a muscular contraction through a directable funnel known as a hyponome, or siphon.
Ancient nautiloids used their tentacles to great effect, becoming major predators in the oceans during the Ordovician period (roughly 488 to 443 million years ago). Many but not all had straight, conical shells like witches’ hats or British traffic cones, and some grew to enormous size: Orthocones and Cameroceras grew at least as long as a man is tall, and perhaps as big as a giraffe. They were the pointy-headed aquanauts of the Ordovician. It’s likely that the baroque spikes on the backs of some trilobites such as Ceratarges may have evolved in order to make them less attractive to such beasts.
The world these creatures ‘ruled’ was very different from ours. The planet span faster on its axis than it does now. A day lasted 21 hours and there were 417 days in a year. The Moon was closer too, and one may picture it, bright and pendulous over the sea, moving fast, seemingly close enough to reach up and touch (as it actually is in Italo Calvino’s absurd and beautiful story, ‘The Distance of the Moon’). The greater proximity of the Moon meant that tides were both higher and lower than we experience today. Growth rates in marine organisms were affected. In the modern Nautilus, tiny ribs or laminations are secreted daily in relation to the lunar-tide cycle. It is these that slowly build up the spiral shell. Today, the creatures typically have twenty-nine or so growth laminations per chamber, corresponding to the length of the lunar-tidal month. The further back in the fossil record you look, the fewer laminations you find. Nautiloids in the Ordovician appear to have had eight or nine per chamber, suggesting the lunar month at that time was only a little longer than a week today
Nautiloids were top cephalopods (and top ocean predators) for tens of millions of years, but from the late Silurian onwards ammonites became much more common, and it was these which evolved into the abundant and diverse species which so impressed Hooke and others, and later helped geologists to reconstruct Earth history. Over their roughly 335 million years of existence, ammonites ‘explored’ the boundaries of size and shape, mapping large parts of the morphological space available to any entity that grows by accretion. Most ammonite shells were flat spirals. Some were tiny but at least one species grew to more than 2 metres across. Others were helical in shape. A few, such as the bizarre-looking Nipponites, took wildly irregular forms. (Nipponites brings to mind what Samuel Johnson said of Tristram Shandy: ‘Nothing so odd will do long.’) But as a group ammonites were remarkably tough, recovering from every punch nature could throw including the end Permian extinction which killed off about 95 per cent of species in the seas until, finally, in an almighty prang at the end of the Cretaceous, they joined the choir invisible.
In another of the stories in Calvino’s Cosmicomics, the protagonist, whose name is Qfwfq, spends a long time as a lowly mollusc condemned to a moment-by-moment existence, a prisoner of the eternal present. Days and nights crash over him ‘like waves, all interchangeable, identical or marked by totally fortuitous differences’. In an attempt to separate his present from all other presents, Qfwfq starts to build a shell, hoping to lay down markers in spiral accretions as if he were making his own clock. He tries to create an extremely long, unbroken shell-time, but an infinite spiral proves impossible: the shell grows and grows and at a certain point stops – and that’s it, finished. Thousands of others molluscs try too but the effort is wasted: ‘time refuses to last, the shells are friable, destined to crumble into pieces. Theirs are only illusions of time that last as long as the length of a tiny shell spiral, splinters of time that were detached and different from each other.’ Eventually, Qfwfq realizes, someone else has to try ‘to ensure that everything that was left or buried [becomes] a sign of something else’. That someone else, Calvino does not need to say, is us: by seeing the links between vast numbers of interrupted spiral shells, and identifying each variety as a sign or marker in evolution, humans have put together a continuous spiral we call Earth history. The geological record is something that other species have lived but no species apart from humans know.
A second wonder of the Nautilus is the internal architecture of its shell. Chambered compartments within, camerae, act as flotation chambers which can be filled or emptied of gas or fluid through an opening called a siphuncle to adjust the animal’s buoyancy. This remarkable adaptation dates back to the animal’s origin. Long before fish evolved swim bladders, nautiloids evolved these chambers as a means to float without effort above the seabed, and to rise and fall as they chose. And this, combined with the ability to control horizontal movement by forcing water through their siphons, enabled the early nautiloids to become the first great death from above.
Flotation chambers may be old hat in the animal kingdom but they are a relatively new and valuable technology for humans. Today they allow us to dive deep in the seas and remain there for long periods. By contrast, diving bells, the first submersibles, merely held a pocket of air whose pressure could not be controlled and whose oxygen would rapidly deplete, and relied on weights and ropes to descend and ascend. The first submersible to sink and rise by flooding and emptying a separate chamber (allowing water into a bilge tank, and pumping it out by hand) was probably the Turtle, developed by David Bushnell in Connecticut in 1775 in order to attack British ships. (Moving through the water, the Turtle may have wobbled and rocked around its low centre of gravity, rather as a Nautilus does; it failed completely as a fighting vessel.) Robert Fulton’s Nautilus, developed between 1793 and 1797 for the First French Republic, was significantly more sophisticated than the Turtle but was no more successful as an engine of war. Its name was probably taken from a supposed similarity – when it was on the surface and under sail – to the Paper Nautilus or Argonaut, which is actually a kind of octopus whose female builds a papery ‘shell’, shaped rather like the shell of an actual Nautilus, and which was believed to sail by hoisting two webbed tentacles above the surface. Whatever else is true, the felicity of the Nautilus name for a submersible was entrenched in the 1870s when Jules Verne gave it to his imaginary vessel in Twenty Thousand Leagues Under the Sea. And the resonance was strengthened when the world’s first nuclear-powered submarine, launched in 1954, was named USS Nautilus. This marked an important step towards the goal, achieved subsequently, of craft that are almost undetectable – always-ready delivery platforms for Intercontinental Ballistic Missiles. A single ‘boat’ armed with ICBMs can destroy most of the great cities on an entire continent and is a must-have for any power aspiring to global reach. So from wobbly beginnings in the eighteenth century, a mechanical-chambered beast has become the ultimate in death-from-below in the twenty-first.
There have been other hopes for submarines besides the perfection of new means of destruction. The first submarine driven by combustion rather than human muscle-power, the Ictineo II of 1864, was developed by Narcís Monturiol, a Catalan artist, engineer and utopian socialist who hoped his creation would save the lives of coral harvesters and help bring prosperity and peace to mankind. In recent decades, submersibles used in scientific research have helped to transform our sense of what and where non-human life can be, providing glimpses of creatures that are stranger than humans have ever imagined.
The Nautilus, a submarine designed by Robert Fulton, 1793–7.
A third wonder of the Nautilus is its eyes. And the marvel here is the opposite of the Gonodactylus discussed in Chapter 7: these are the simplest eyes of any large living animal – lensless ‘pinholes’ that project a hazy and rather dim image onto its retinas. Much smaller creatures such as the common European land snail, the winkles and the periwinkles have lenses in their eyes even though those eyes, at no more than a millimetre across, are a tenth of the diameter of those of the Nautilus. The Nautilus’s pinholes allow it to tell day (when it hides in the depths) from night (when it rises to feed near the surface) and to orient itself with respect to large objects such as rocks when it is near the surface. But that seems to be about it. Measured by maximum resolvable spatial frequency, they have worse acuity than those of a horseshoe crab (3.6 cycles per radian compared to 4.8), less than a hundredth that of a goldfish (409), and well under a thousandth those of an octopus, human or eagle (2,632, 4,174 and 8,022 respectively). Smell probably plays a larger role in guiding their beaks and radula (‘tongues’ embedded with tiny teeth) towards food: rhinopores below the Nautilus’s eyes are capable of detecting odours up to ten metres away. Its tentacles also have chemoreceptors, which allow them to detect prey close by.
Crude as they are, however, pinhole eyes are evidently useful to the Nautilus, and something like them has probably gazed at the world (albeit murkily) for nigh on 500 million years. Any natural history of vision needs to take them into account. Further, their persistence can stand as a reference point in our own development of ‘artificial eyes’ – the cameras and image-recording systems that were initially extremely crude but which have profoundly affected the ways in which we perceive and value the world.
The first step towards the creation of a mechanical eye entailed the harnessing of a natural phenomenon that people have probably been noticing since they became people. On a bright day, little images of the sun are sometimes projected through small gaps between the leaves of a tree onto the ground below. In the late fifth century BC the Chinese philosopher Mozi and his followers built what they called a ‘locked treasure room’ which projected an image of the bright outside world through a tiny hole onto a dark wall: the first camera obscura. (Mozi taught logic, self-knowledge, authenticity and universal compassion; his work was energetically suppressed.) In Greece, Aristotle and others also had a good grasp of the principles of this device, and increasingly sophisticated versions were described or made over time, possibly in Byzantium and certainly by natural philosophers of the Arab golden age such as Alhazen, as well as in China. By 1591 a version existed in Italy which had a lens rather than merely a pinhole, and by 1600 Johannes Kepler in Germany was using one to observe the Sun and the transit of Mercury. More compact and portable versions were developed later in the seventeenth century, and used increasingly widely thereafter by draftsmen and painters.
The images of the world created by a camera obscura continue to flow exactly as the world around the camera flows. But an image that is fixed on a medium such as photosensitive film can create something different, and remarkable: the impression that an actual moment (or at least something true to it) has been removed from the flow of time and placed beyond it. A camera that records images seems to be a kind of time machine. Today we are so accustomed to this phenomenon, whether in stills photography or moving images, that we usually don’t give it a second thought. But there is something extraordinary and profound going on here, and it is worth trying to look at it afresh.
As for many people my age, making a pinhole camera and taking a picture with it was a standard project in science class when I was about thirteen. We were each given an empty tin can with one end removed, and a tool to pierce a small hole in the centre of the other end. Then we covered the hole with a ‘shutter’ of masking tape, and in darkness sealed a strip of unexposed film on a card inside the open end of the tin. And then we were allowed out (!) on a bright sunny day to look for places to take pictures. I positioned my camera and exposed the film onto a view from the top of a building at the corner of a square with the two towers of Westminster Abbey beyond. When, the following day, we developed our films, we found that most of us had been successful. In my attempt you could see the receding horizontal and vertical lines of the roofs edges, walls and windows quite clearly, thanks to sharply contrasting shadows and bright patches. I was entranced: the image captured a moment on a sunny day and somehow carried it forward into the next, which happened to be grey and overcast. This image was not ‘merely’ memory or imagination in the human brain but to all appearances something real. Streams of actual photons that had been part of the material reality of that day had left an enduring mark. Heraclitus is reported to have said, ‘all things move and nothing remains still’. Our photos made this seem not quite true.
The conundrum of movement-and-stillness is apparent from the beginning of photography. The View from the Window at Le Gras taken by Nicéphore Niépce in 1825, which shows the prospect across an open space between two buildings according to established Western ideas of composition and perspective, is in many respects a simple and crude image. But this photograph, grainy in the extreme, carries a powerful charge for us today because we know it to be the first freezing of a moment, however mundane, in a photograph, a moment that passed long before the memory of anyone alive. Also, as an incidental result of the primitive technology used to make it, the image enables us to reflect on what constitutes a moment in time. Niépce had to expose his film to bright sunlight for eight hours or more to capture an impression and as a result sunlight and shadows fall on both sides of the view. The moment in this image is therefore simultaneously a second or so – the time it takes the viewer to look at it – and eight hours long. It is a view such might be seen by an infant lying in a cot and learning to organize the stream of impressions flooding in, or by an adult immobilized by grave illness and on the threshold between reality and death.
Within twelve years Louis Daguerre had discovered how to record an image with film that only needed to be exposed for eight minutes. His view of the Boulevard du Temple in Paris is vastly superior to Niépce’s earlier work in clarity and detail and, momentously, was recorded quickly enough to capture what is probably the first photographic likeness of human beings. You can see them in the lower-left quadrant: a man standing patiently with his leg up and thrust forward onto a stool while another, seated, shines his shoe. Any passers-by on this busy street have left less impression than ghosts. These two figures are, perhaps, the first example of what Roland Barthes, writing in the 1970s, called a ‘punctum’, by which he meant a spark of contingency which punctuates both the homogeneity of a photograph and the emotional detachment of the viewer. The image of the Boulevard du Temple is where photography begins to find itself as an extension of human consciousness.
In David Octavius Hill’s 1843 portrait of himself and his daughter the punctum is Hill’s right hand, placed firmly and lovingly on the girl’s head. The immediate contingency here was the need to hold the little girl’s head still for the several minutes that the exposure required. The poignancy, however, arises inevitably in the mind of the modern viewer who learns that Hill could not save his daughter from an early death and who also knows that Hill, for all his tenderness and strength, is also long gone. In the words of Barthes’ contemporary Susan Sontag, ‘photographs state the innocence, the vulnerability of lives heading towards their own destruction’.
Reflecting on the nature and significance of photography some fifty years before Barthes and Sontag, Walter Benjamin had suggested that the earliest surviving photographs shared something of the ‘aura’ of older religious objects and works of art because they remained unique; special precursors to the contemporary age of mechanical reproduction. Later, Benjamin changed his view, maintaining that even a photograph taken in the age of mass production could have an aura – a ‘magical’ quality of preserving a sense of immediacy even across temporal distance. It is this latter view that makes more sense. The really important matter is what is being recorded. For Benjamin this was particular people (notably, Franz Kafka as a small boy): ‘To do without people is for photography the most impossible of renunciations.’
David Octavius Hill with his daughter Charlotte circa 1843.
For most of us most of the time, Benjamin’s observation remains true: photos of those we love are usually the most precious images we have. But photography, film and other image-capturing technologies have, of course, also evolved vastly beyond what Benjamin ever contemplated. Digital imaging now makes possible the creation of increasingly convincing images of worlds that never were or will be, and simulacra of past and future realities we will never see. What the impacts of these developments will be has yet to be fully determined, but already, at the very beginning of the age of moving images, H. G. Wells in The Time Machine (1895) anticipated some of their disruptive power and the sense of vertigo that results:
The twinkling succession of darkness and light was excessively painful to the eye. Then, in the intermittent darkness, I saw the moon spinning swiftly through her quarters from new to full, and had a faint glimpse of the circling stars. Presently, as I went on, still gaining velocity, the palpitation of night and day merged into one continuous greyness; the sky took on a wonderful deepness of blue, a splendid luminous colour like that of early twilight; the jerking sun became a streak of fire, a brilliant arch in space; the moon a fainter fluctuating band . . . I saw trees growing and changing like puffs of vapour, now brown, now green; they grew, spread, shivered and passed away. I saw huge buildings rise up and pass like dreams. The whole surface of the earth seemed changed – melting and flowing under my eyes.
One characteristic of image-capture technologies is that instead of revealing reality to be solid they help to show that the world is always changing. Yet, in a seeming paradox, these technologies also reinforce our sense that moments of time – snapshots – may be ‘all’ that there is, or at least all that matters to us because consciousness is situated only in those moments – a feeling vividly delineated in Chris Marker’s 1962 film La jetée.
With photography, motion pictures and the rest, we have both enhanced and altered our sense of what it is to be. And yet we also learn that on the scale of things as they really are the view available to us as conscious beings is not much better than that of countless generations of the Nautilus floating through black water under an obscure moon before they are cast up, lifeless, on a shoal of time.
