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Ten Million Aliens

Page 37

by Simon Barnes


  Every now and then, Britain gets a painted lady year: a year with vast numbers of this rather special species of butterfly. They migrate up from Morocco in wildly fluctuating numbers. For a long time this migration was considered an evolutionary anomaly, or Darwinian cul-de-sac. The butterflies flew up to Britain, arrived in numbers, bred: and then simply vanished. It was assumed that this was a doomed generation, an experiment that continually went wrong, the butterflies pushing too far north to make a go of it. But in recent years painted ladies have been observed making the return journey: a greater miracle even than their miraculous appearance.

  In Britain it is generally accepted that there are 59 species of butterfly and around 2,000 of moths, including the tiny and mysterious micromoths. In the world there are, as we have seen, not far short of 200,000 species of Lepidoptera. Many of them are staggeringly, outrageously, almost absurdly beautiful. And how many names do we have for them in common use? Two. Butterfly and moth. You could hardly get better evidence for the inability of non-specialised human vocabulary – and therefore of humankind – to come to terms with the diversity of the Animal Kingdom.

  So let me close this chapter by telling you the easiest way of increasing your own appreciation of biodiversity. You don’t even have to leave your own garden. Most of us can name two or three butterfly species. Get a bookII and see if you can’t get into double figures. And that’s it. Simplicity itself. You can do it with a cold drink in your hand: sip, look, and then look for a name. Part of the magic of names is that they make you look more closely and more often. A name changes the way you look for, and once known, a name changes the way you look at. Sitting in a garden on a nice sunny day, preferably with a nice sunny drink, is an exercise in increasing your understanding of biodiversity: that is to say, understanding the basic mechanism that supports life on this planet.

  * * *

  I. From Alice in Wonderland, of course.

  II. Try A Pocket Guide to the Butterflies of Great Britain and Ireland by Richard Lewington.

  No bones about it

  It seems obvious now that the taxonomists have explained the puzzle. How could sharks and their relatives ever be confused with the ray-fins? The difference goes bone-deep. I’d say marrow-deep, but sharks don’t have bone marrow, not having bones as we know them.I Instead, they have a skeleton made of cartilage: flexible, tough, lightweight, elastic. They start off with a notochord, the incipient spine that is found in all vertebrate embryos, our own, of course, included, but with the cartilaginous fish this is gradually replaced by cartilage. It is a unique strategy among us chordates, which explains why the group – the Chondrichthyes – have so singular an appearance.

  The weirdest are the chimeras or ghost fish, 34 species and all of them odd, even monstrous. They are sometimes called rabbitfish, because of their fused, plate-like teeth, and they include ratfish, elephant fish and charmingly, a spookfish. They look rather like bad drawings of fictional monsterfish intended to horrify a not overcritical audience of children. There are some creatures that, when you see them illustrated, or even photographed, look so strange you can’t believe they seriously exist. They look too much like an artist’s fantasy.II The chimeras demonstrate that principle to perfection.

  The second and much larger group, the Elasmobranchii, includes sharks, already discussed, and rays. Sharks and rays have taken opposing strategies. Sharks, as we know, are streamlined and forever moving forward. Rays and skates have gone the other way, abandoning streamlining and sinking to the bottom. Sharks must keep moving forward in order to breathe, for they need the passage of water over their gill slits. The rays have taken a different evolutionary direction and stillness is no problem to them: in fact, it is the foundation of their existence. They breathe by taking in water through their spiracles, small holes behind their eyes, and out through their gills. They are adept at concealment, and feed on other bottom-dwellers, mainly molluscs and crustaceans.

  They have taken on a flattened, non-streamlined shape, with their pectoral fins fused to their heads. They swim with a rippling motion, for preference close to the sea bottom, so that they seem to glide frictionlessly over the floor, like the puck in a game of air hockey. Their eyes are on the top of their heads, which is fine for spotting potential predators, but it means they can’t see the animals they pursue themselves. They hunt them out with smell and with electrical receptors instead: an extreme example of compartmentalisation of the senses. They have a reputation for intelligence, some say they are smarter than sharks.

  Stillness makes an animal vulnerable, so the rays have evolved more than one counter-strategy. They bury or half-bury themselves in sand, and most species are neutral coloured and tend to blend into the background. Some species are well camouflaged. Stillness can be effective, since it’s movement that catched the eyes, on solid ground or underwater, but all the same it helps to have a plan B. Anyone who has taken a walk in the English countryside knows about plan B: a pheasant will keep dead still until you are right on top of it, and then it will leap clumsily into the air while making the most terrible din. It makes you jump: it’s supposed to. The noise is designed to freeze the predator for a vital half-second while the pheasantIII escapes. Some rays have a different but equally effective plan B: attack.IV Stingrays carry one or more spines on their tails equipped with venom, and will use it in self-defence. Some of the big species carry truly fearsome weapons, with a sting 35 cm or 14 inches long.V Steve Irwin, the Australian television presenter, died after being pierced in the chest by a stingray.

  The group also includes the sawfish – and even as I write the words I seem to recall a sawfish displayed in Birmingham Museum not far from the Japanese spider crab. It was worth a good stare: a toothed blade that looked infinitely capable of sawing down an oak. It is used as a kind of scatter-gun weapon for slashing through a shoal of small fish, and it has a secondary use as a mud probe. Sawfish can reach 6 m, 20 feet, in length, with a saw 6 feet, 1.8 m, long and 30 cm or a foot wide. You look for an evolutionary pattern, find it – and then just about every time, you come across an oddball, something that really doesn’t fit in. Moral: wildlife is not trying to please the human mind. It seldom conforms to the human mania for tidiness.

  * * *

  I. So how do they make red blood cells? The answer is the spleen, the epigonal organ which is found near the gonads, and the specialised Leydig’s organ. The chimeras possess neither of the last two.

  II. Among us mammals, the aardvark is the leading example of this principle.

  III. That’s why pheasant shooting is an unfair competition: the pheasant strategy is to lie low, and then as a last resort, to make a predator jump. So the beaters startle the pheasant into flight – and only then, when the pheasant has exhausted its evolved options and is vulnerable, do the guns open fire.

  IV. A classic example of the old adage: “This animal is dangerous: it defends itself when attacked.”

  V. There are stories of a stingray’s tail being used by humans as a whip to chastise slaves and errant wives. The British government made them illegal in Aden. A stingray whip appears in the James Bond short story, already quoted in his book, “The Hildebrand Rarity”.

  Inordinate fondness and all that

  Beetles have four wings, in the classic insect pattern, but their forewing has become a hard, thick sheath. Beetles make up the order of Coleoptera, which means sheathed wing. When they fly – most beetles fly – they flip up the modified forewings and leave them there, so they look as if they are flying with the doors open. In this fashion they power themselves along effectively enough with their hindwings. Which means they can move in confined spaces without damaging their wings, so they can still fly.

  What’s so bloody marvellous about that?

  I mean, it’s quite a neat trick, I wouldn’t deny that for an instant, but it’s hardly the most brilliant piece of adaptation in the entire history of life, is it? Compared to a shark’s teeth, an albatross’s wing, an elephant’s t
runk, a human’s brain, a mosquito’s mouthparts, a waterbear’s unkillability or a termite’s social life, the fact of sheathing a wing doesn’t strike me as one of the BeamonesqueI evolutionary leaps in the story of life on this planet. No one making a display of the wonders of nature for children would say that the most wonderful thing of all is that beetles can tuck their wings away behind a small fragment of armour. Sheathed wings are not going to inspire gasps of amazement and a determination to look after the non-human life of the planet better than before. But this adaptation has made beetles the most impossibly, the most brilliantly, the most startlingly diverse aspect of life on earth. Of life in the entire universe, for all we know.

  Let’s take some numbers: 25 per cent of all known life forms are beetles; 30 per cent of all animal species are beetles; 40 per cent of all described insects are beetles. There are getting on for 400,000 species of beetles already described and more are being found every year, or every day. Estimations for the number left to be described vary from a million to 100 million – and even a mere million is quite a lot, if you think of that in terms of pounds or dollars. The most famous line about beetles comes from JBS Haldane, who we have already met in these pages via his queerer-than-we-can-suppose remark about the universe. The story – there are many variants – is that Haldane was asked by a theologian what he could deduce about the nature of the Creator from a lifelong study of His Creation. Haldane’s response: “An inordinate fondness for beetles.”II In an essay written later, Haldane expanded the thought: “The Creator would appear as endowed with a passion for stars, on the one hand, and for beetles on the other, for the simple reason that there are nearly 300,000 species of beetle known, and perhaps more, as compared with somewhat less than 9,000 species of birds and a little over 10,000 species of mammals. Beetles are actually more numerous than the species of any other insect order. That kind of thing is characteristic of nature.” (Note, by the way, that Haldane’s numbers are no longer in fashion.)

  Alfred Russel Wallace, Darwin’s co-discoverer of the principle of evolution by means of natural selection, once wrote in his notebook: “It is a melancholy thought that many of our fellow-creatures do not know what is a beetle! They think cockroachesIII are beetles! Tell them that beetles are more numerous, more varied and even more beautiful than the birds or beasts or fishes that inhabit the earth and they will hardly believe you, – tell them that he who does not know something about beetles misses a never failing source of pleasure and occupation and is ignorant of one of the most important groups of animals inhabiting the earth and they will think you are joking, – tell them that he who has never observed and studied beetles passes over more wonders in every field and every copse than the ordinary traveller sees who goes round the world and they will perhaps consider you crazy, – yet you will have told them only the truth.”

  Darwin spent much of his youth in pursuit of rare beetles, much as modern twitchers chase rare birds across Britain, filled with love of wild things and inflamed with collection mania. (Perhaps if Darwin had had a car and a mobile phone and a pair of top-of-the-range modern binoculars he would have become a twitcher, for it is much the same sort of obsession.) Darwin wrote in a letter: “But no pursuit at Cambridge was followed with nearly so much eagerness or gave me so much pleasure as collecting beetles. It was the mere passion for collecting, for I did not dissect them and rarely compared their external characters with published descriptions, but got them named anyhow. I will give a proof of my zeal: one day, on tearing off some old bark, I saw two rare beetles and seized one in each hand; then I saw a third and new kind, which I could not bear to lose, so that I popped the one which I held in my right hand into my mouth. Alas it ejected some intensely acrid fluid, which burnt my tongue so that I was forced to spit the beetle out, which was lost, as well as the third one.”IV

  In other words, the two men who were responsible for unravelling the greatest mystery of life both suffered from beetlemania. This is not the weirdest of all possible coincidences; beetling and bug-hunting were more mainstream activities in Victorian times. During his beetling days, Darwin thought he might fancy the life of a parson naturalist, and would have joined a long tradition had he done so. It is tempting to describe beetle numbers as “head-spinning” or “mind-boggling”, and so they are for most of us. But neither Darwin nor Wallace had minds that did much boggling. When their minds were stimulated they looked for solutions. Darwin’s mind always reminds me of a description of Karz, the bad guy in one of the Modesty Blaise novels.V “There was finality in Karz’s voice. The sloe-black eyes went suddenly blank. Liebmann knew that Karz had finished with the subject, withdrawn his mind from it. His thoughts were occupied by some other aspect of the massive and complex operation. He might sit for five minutes or five hours, until his mountainous mind had crushed the problem out of existence.” Karz essentially represents the forces of anti-life: Darwin quite the opposite. Darwin’s mind was mountainous all right, but his problem-solving nature was profoundly life-affirming. There is a deep joy to be found in Darwin’s works, and it comes first from the writer himself. That joy can be found again in the way we look at life on earth after he opened our eyes to its meaning.

  And the fact is that Darwin did crush the problem, slowly and laboriously and inevitably grinding it to a pulp with the rock-crushing mechanism of his mind. It is easy to tell what creatures took him there: everything he had ever seen and chased and shot and caught and observed and missed and spat out. But my view is that it was the inordinate numbers of beetles, the extraordinary and apparently endless variety of beetles, that first told him – in a subtle, sleeping, unrealised form – that there was a massive question out there that needed answering.

  As for the beauties of beetles, come boating with me in Southeast Asia. I have experienced this miracle twice, in Borneo and in peninsular Malaysia: a riverbank illuminated by beetles: an entire tree that turned itself on and off, like a neon sign in Piccadilly Circus or Times Square, lighting up the branches and the quiet waters beneath with a cold and mysterious otherworldly light, like the lanterns carried by the gnomes of CS Lewis’s Underworld. In stately, deliberate rhythm they flashed on, they flashed off, they flashed on again. Here was a group, a gathering, a swarm of fireflies all acting as one, and for the same rich purpose: to find mates, to make more fireflies. Americans call them lightning bugs; there is a species that goes in for the same sort of synchronous flashing in Great Smoky Mountain National Park. And these flies are not flies, and these bugs are not bugs. They’re all beetles, like practically everything else that lives: part of the overwhelming, world-solving, inordinate numbers of beetles. So I should add, then, that there are 2,000 species of fireflies or lightning bugs, and there are some that will flash the code of the wrong species to dupe an ardent mate-seeking firefly and then devour it. Adaptations within adaptations within adaptations: queerer than we can suppose: just a couple of the beetles’ greatest hits.

  * * *

  I. Bob Beamon (already met in these pages as a comparison with leaping bushbabies) was the athlete at the Mexico Olympic Games who broke the world long-jump record of 29 ft 21/2 in, 8.90 m, beating the previous best by an impossible 213/4 in, 55 cm. He set a mark that wasn’t beaten for almost 23 years.

  II. I have two books of this title; the first a textbook about beetles by Arthur V Evans, and the second a splendidly flaky account of Alfred Russel Wallace by Paul Spencer Sochaczewski. The quotation by Wallace in this chapter comes from this book.

  III. Cockroaches make up an order of their own, the Blattodea. There are about 4,500 species – about as many as they are mammals – and 30 of them are associated with humans.

  IV. This was the crucifix ground beetle, thought extinct in this country but recently found in Wicken Fen in Cambridgeshire.

  V. Sabretooth, quoted earlier with reference to whelks.

  Ray of sunshine

  Who has not played the great game of counter-factual autobiography? I suspect all three of my publi
shed novels started from that premise, the third from the almost universal experience of wondering what would have happened if instead of breaking up so traumatically, you and that person from back then had got still more traumatically married. What if I’d gone to Africa instead of Asia when I was young? What if I’d stayed in Asia instead of going back to England? What if I’d gone to Australia? What if I’d discovered horses when I was young enough to have got seriously good? What if I’d learned to dive? What if, negatively buoyant, I had taken to the sea and fallen in love with cetaceans and all those wonderful things we sometimes call fish, instead of birds and the big mammals of the savannah?

  I was having dinner with a family, old friends all, and in the course of it I let slip that I was planning a chapter on manta rays. As one person, they chorused: how wonderful these creatures are, how seeing them, swimming with them, being with them was one of the most wonderful experiences of all their lives. For they all dive, often all four together, and are all well-practised diving buddies. They have been doing this since the younger ones were children. But I have never dived, never seen a manta ray, and my life is poorer as a result. My imagination has always been haunted by these most unearthly, most unoceanly of creatures: creatures from another world, oceanic angels with broad, broad wings, creatures twice as wide as they are long, paying a brief visit to this strange planet full of aliens ten million and more strong. I can see myself beneath as one passes, turning my entire body, not just my neck, as you can when moving almost weightless in three dimensions, to stare up at the great shape above: the vast winged cloud interposing itself between me and the sun, not swimming, not even flying, but gliding overhead.

 

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