by Simon Barnes
Not stupidity, then. This was a perfectly adapted animal that failed to cope with radically changed circumstances. All the things that prepared it for life on the Galapagos were not enough to cope with something completely different. When such circumstances are reproduced on a large scale, extinction follows. Was this hurled and defiantly swimming marine iguana yet another of those sleeping influences?
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I. The passage is quoted by David Quammen in his excellent essay “The Flight of the Iguana”, published in a collection of the same name.
The Kalahari Ferrari
What does it mean, not a true spider? The phrase baffled me as a child. Anything that ran about on eight legs seemed to express a very clear truth, and not a terribly welcome one. The idea of animals being untrue raised a small turmoil in my mind whenever I came up against it. Seals, I remember reading, had sharp teeth and lived by catching and eating things, but they weren’t true carnivores (although of course they are now). Pandas, on the other hand, though they don’t touch meat in the normal way of things, were true carnivores, and still are.
There are an awful lot of species out there that look pretty much like spiders and which belong in the class of arachnids, but are not spiders at all. There is a gulf between true spiders and untrue spiders. Arachnids also include quite a few species that don’t look anything like spiders: creatures that look as if they should be classified quite differently. They all fit into the subphylum of chelicerates, which includes arachnids, along with the smaller groups of horseshoe crabs and sea spiders – which, I should add, are not all that closely related to true spiders. The point to a zoologist is that they all share a one-piece head/thorax combination. I trust I make myself obscure.I Perfectly? Then let us continue.
Some animals are capable of alarming you because they can kill you, others because they give you the creeps, still others because they make you jump. Mice and bats fall into the last category, but by far the best are the sun spiders or solifugids. Latin for fleers from the sun. Not, of course, true spiders. They share a common ancestor with spiders but have diverged to form a separate group: I put in that clarification for my childhood self. One difference is that most spiders do a lot of hanging about. Solifugids don’t. As the sun goes down they get going. Instead of waiting to see what the world will bring them in the way of food, they set off at top speed until they bump into something edible. They tend to have a preferred racetrack, and they go round it again and again. They can reach speeds of 16 kph, 10 mph, which seems at least twice as fast in a confined space. When this space is somebody’s living room and you’re sitting in it having a civilised conversation, this can be rather startling. Solifugids have a fine knack of making you think they have given up and gone away before reappearing at breakneck speed, making you – all right, making me – emit a girlish squeak and pour a tablespoon or two of cold beer onto my crotch. They have a great nickname: the Kalahari Ferrari.
Harvestmen, another group of arachnids that don’t count as true spiders, are disturbing in a quite different way. They have incredibly long, thin legs, horrifyingly fragile things of cobweb thinness which support in the middle an unnaturally tiny body: or to be more accurate, an unnaturally tiny abdomen plus head/thorax combo. They appear over baths, looking as if they’re about to fall apart and drop bits of themselves all over youII… but perhaps I am telling you more about myself than harvestmen here. Arachnids comprise around 65,000 described species. A lot of them are tiny, but still look pretty alarming under magnification. Mites are many and various, some feeders on detritus, some predators, some parasites. They include ticks, which feed on blood.
Scorpions are also arachnids. There is a glorious set-piece in one of Gerald Durrell’s books, in which Gerry’s brother Larry opens a matchbox to light a cigarette and finds, instead of matches, a scorpion and young: “It’s that bloody boy… he’ll kill the lot of us… look at the table… knee-deep in scorpions…” Every morning when I am in the bush I bash out my boots before putting them on, to shake out the scorpions. I’ve never found one yet: not a detail that will stop me banging. There are a couple of thousand species of scorpions, and the championIII is 20 cm or 8 inches long. I’m pleased to tell you that “only” 30 or 40 species carry venom strong enough to kill a human. Even scorpions are wary of scorpions. When they court, they seize each other by the pincers, so each can dissuade the other from turning an amorous encounter into a cannibalistic feast. When I was at Sunnyhill Junior School we were shown a Walt Disney film of this behaviour. It came, alas, with comic music, as if the scorpions were doing a silly dance to amuse humans: the darkened classroom was filled with silly glee. I still remember my hot-eyed fury at this. I couldn’t bear the thought that people thought animals silly. Surely if anyone was silly here, it was humans. No animal has been put on earth to amuse humans: to think so is demeaning to my family and to other animals. True spiders, untrue spiders and all their fellow arachnids may give me the jumps, but that’s my folly and failure.
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I. As Sir Thomas More says in Robert Bolt’s A Man For All Seasons. Do something as a school play and it’s likely to stay with you for life, which is a good argument for schoolteachers choosing only the greatest plays.
II. And as a matter of fact, they often do precisely that. They make up the order Opiliones, which comes from the Greek for shepherd, so named because shepherds in some places performed their duties on stilts.
III. Hadogenes troglodytes, the South African rock scorpion, or flat rock scorpion. Only mildly venomous.
Good luck, little metaphor
Tiny, and swimming hard between my finger and thumb as I picked him up from a plastic washing-up bowl, away from his brothers and sisters. All of them were flippering and flappering as if their lives depended on it, and for the best of reasons. Tenderly, I placed him on the black sand of the beach: unhesitatingly he set off. Towards the sea, not away from it: the compass sense that will guide his swimming sisters back to the same beach to lay eggs of their own drives the young turtle towards his destiny in the waves. I set another four on the same trail; soon here was a line of turtles going through a ritual not unlike birth: the transition from the allwombingI beach to the perilous and enthralling sea.
I was on the Pacific coast of Colombia where the hot, wet forest comes right down to the sea and the humpback whales rise and breach in the waters within sight of the shore. I was visiting a project for the olive ridley sea turtle. Their eggs are gathered from the nests on the beach and kept safe: safe from hungry humans, safe from feral dogs, safe, too, from other turtles, who come onto a crowded nesting beach and accidentally dig up each other’s nests. At the project headquarters the eggs are watched and monitored and when hatched, the turtlings are released with the sea before them. That way close to 100 per cent of the hatchlings reach the sea: that’s already far better than anything that could be hoped for in the crowded modern world. But it’s still a dismaying sight: these tiny creatures setting off so optimistically into so cruel a world – well, it rather breaks your heart. I might have got us all drowned, or at least stuck, because I refused to leave the site of the release until my – that should be “my” – turtles had reached the sea. The driver of the waiting vehicle had to perform minor heroics to beat the incoming tide and get us to our destination. But no one can walk away from a seaward-scrabbling turtle.
Television programmes have made this an enduring image of the vulnerability of nature: turtles forever striving for the sea. It has become an image of blind hope within the hopelessness of life: many boys seek to become professional footballers and as few make it to the top as turtles make it to adulthood. It’s also an example of the way humans take advantage of weakness: a trusting turtle lays a cache of eggs, only for the hard work to be undone by endlessly hungry people. You see turtles walking towards the sea and you say: this can’t possibly work.
Of course, if you take out the unsustainable harvesting of the eggs by humans, the strategy works very well i
ndeed and has done for millions of years, since long before humans were around, since long before mammals had much of a say in what happens on this planet. A female can live 20 years and more, each year laying one, two, or even three batches of eggs, each one of more than 100. Conservatively, that’s 3,000 eggs: 3,000 spins of the roulette wheel. If only one of these survives to adulthood and breeds in its turn, she’s fulfilled her minimum biological ambitions; the same rule works for the males. In a pre-human world that’s pretty decent odds, as the survival of the species makes clear. It’s only in the last century that things have changed.
A female might be covered by eight males for each batch. Each male is capable of fertilising a number of eggs in the same clutch, while the sperm itself competes within the female. Olive ridley sea turtles are not giants, but they’re capable of reaching a decent size, the females up to 46 kg, more than 100 pounds, and 70 cm or 2 feet 3 inches in length.
Turtles, terrapins and tortoises make up the order of Testudines: an easy-to-follow bit of taxonomy, since they all dwell in a private armoured car (or ironclad water vessel if you prefer): a carapace above, a plastron below. There are about 300 species of them in 14 families. The giant tortoises of Galapagos may have been another of those sleeping influences on Darwin: certainly, they provide another of those look-behindjer moments in The Voyage of the Beagle. Darwin, being a young naturalist, accepted what he had been told: that the tortoises were exotics, brought there and dumped by humans. The prisoners from the penal colony there said that each island had a different tortoise: the vice-governor said that he could tell a tortoise’s island of origin from one glance at the shell. Darwin could have made a hefty collection of tortoise-shells: nothing easier, since there were many lying about, often used as flowerpots after the animals had been caught and eaten by humans. But he moved on: and those who visit the Galapagos can look at the tortoises and understand them as a classic demonstration of the workings of the principle that we now call Darwinism.II
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I. A Joycean coining.
II. Darwin did, however, notice the mockingbirds of the Galapagos. He realised that the mockingbirds on Charles Island differed significantly from those on Chatham. So he labelled his mockingbirds island by island – and it was the mockingbirds, and not the more famous finches, or the iguanas or the tortoises, that unlocked the mystery of life. Darwin’s revelation was itself mocked without mercy, or for that matter thought, before it obtained scientific acceptance.
Twenty centimetres!
When I first arrived on Lamma Island, I was naturally greeted with horror stories about the terrifying wild creatures that would visit my ground-floor flat. Being even then something of a traveller, I laughed them off. And I was right to do so: the hard-bitten hard-biting centipede that had been so graphically described turned out to be a millipede: no rapacious carnivore but a charming vegetarian, bumbling across the floor with the air of an absent-minded Tube train that had forgotten its tunnel. I gently removed it from the house in the dust-pan: it even had the courtesy to curl up like a liquorice allsort as I did so.
And then, of course, the real centipedes started arriving: large, fast, fierce and wriggling hard. These are impressive and alarming, and they can bite. Everybody on the island had a centipede story or two. I was awoken at night by a tinkling sound from the electric fan above my head. We argued: something’s there no there isn’t yes there is no there isn’t go and look there’s no point turn the light on oh ALL RIGHT. As I did so a 6-inch-long centipede fell from the safety cage surrounding the fan to land on my pillow. A nip from one of these things can hurt: my neighbour Sam was bitten on the balls and even he, a person of infinite good humour, found it hard to laugh that one off. Bloody funny for the rest of us, of course, and hardly the worst thing he took to his bed that year, as we all heartlessly agreed.
Then there was a pretty and charming Frenchwoman who lived on the island for a few months. She too was troubled by a nocturnal invader, and she made a terrified small-hours phone call of distress to Chris. Chris solved everybody’s problems on the island: he was that sort of man. Just how many problems he solved that night must remain the subject of speculation, but the French lady contributed one memorable phrase to the story. She was much moved by the whole encounter and was inclined to tell the tale again and again, always returning to the same phrase: “It was twentee centee-meetairs!” Twenty centimetres!
The unsporting A Colour Guide to Hong Kong Animals gives a maximum length of 13 cm to what it calls the urban giant centipede. I have found other reports of the same species, now called more simply the giant centipede,I up to 8 inches. But if you seek a giant worthy of the name, look for Scolopendra gigantea, the Peruvian, or sometimes the Amazonian, giant centipede. It can reach a foot and more – thirtee centee-meetairs! – and preys readily on vertebrates.
Centipedes and millipedes are all part of the same group of myriapods, which contains 13,000 species. They all have segmented bodies: millipedes’ segments are fused in pairs so that they appear to have two pairs of legs to each segment; centipedes very clearly have but one pair per segment. Millipedes are mostly found in wet forest where they eat decaying plant matter and play an important role in the commodius vicus of recirculation that keeps the rainforest forever self-renewing. None has a thousand legs: Illacme plenipes, already mentioned in these pages, is the champion with 750 legs. Some species have fewer than ten legs, which seems hardly fair. The pill and box millipedes have abandoned the Tube-train body plan and contracted to become short and bulbous.
Myriapods are fine beasts and worth a chapter. But now we must leave them and every other class of rthropod and every other phylum of invertebrate alone, for it is time to enter the last class of the inverts. And I have saved the greatest for last.
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I. Common names, or vernacular names, are a constant source of confusion, and people are always making doomed efforts to tidy them up and rationalise them. Some people insist that we call the robin the European robin, and that we call the bearded tit the bearded reedling, because it’s not closely related to tits. I rather enjoy the chaos myself: it’s part of the great Babel of world language. If you want precision, you have the designedly unambiguous scientific names. At least, that’s the idea, but here the names are constantly changing in response to new discoveries. The point is that common names reflect intuitive taxonomies rather than scientific ones. As such, they are as valid in their way as organised scientific taxonomy.
Shape-shifters
I have perpetrated a gross libel on Sunnyhill Junior School, Streatham. I can clearly remember one incident in which I received an important bit of education from that establishment. It was the time when we did frogspawn. There in the classroom was a glass tank containing the black-blobbed jelly that was awaiting its destiny. It was strange: as if the other 44 members of the class were to be given a guided tour of my world. Not that I had ever seen the miracle associated with frogspawn for myself, for in those days most of my engagement with wildlife was platonic. I read about it, I thought about it, I was deeply in love with the idea of it: but all without physical reality. It was, back then, an affair of the mind. Which made the time of the frogspawn especially vivid.
The spawn hatched out into tadpoles. How unlike a frog! These tubby little black torpedoes looked as if nothing could be further from their minds than hopping, leaping, catching flies and going ribbit-ribbit.I They were fish with destiny: destiny’s larvae. They swam about and breathed through gills, and if you were to drag them out of their tank into the deadly air of the classroom, they would drown as a fish drowns. They had no legs: they swam with their tails. They fed on algae and plant matter. But gradually the changes came: the emergence of back legs, which in a day or two were used for propulsion. The tail began its retreat, the front legs appeared: and then they were not tadpoles at all; just minutely perfect froglings ready to start a life on land, living not on plants but insects, breathing not through gills but lungs.
Seeing this for myself was not like reading about it. Seeing this transition made me wonder. Here was an animal that turned into a completely different animal: vegetarianII to carnivore, water-breather to air-breather, legless swimmer to four-limbed leaper, a creature restricted to water to one with the great solid world before it. I wondered if I was a kind of larva too, if I would be radically different when I grew up. But no, that wasn’t the case with humans. I could see that it was only a difference in degree, in size, in proportion, in strength, in mental power, in sexual awareness. I was not a fish that would become a man: I was a boy already timidly growing towards manhood. Not the same thing at all. What was it like, then, for a tadpole, its mind circumscribed utterly by its need to be in water, to be suddenly confronted with the vast impossibilities of land? Did it take it all in its stride and hop boldly on as if it were the most natural thing in the world? Or did it feel a strange twinge of apprehension, a feeling of, this can’t be right, can it?
Not the most scientific approach, it’s true. Perhaps I knew that at the time. But all the same, it was an appropriate response to the impossible fact of metamorphosis: shape-shifting: moving from one state of being to another. Oh yes, sure, a great metaphor for human development in a bildungsroman sense of the term, but as a real, happening non-metaphorical thing its impact was much greater. Your scientist landing from Mars or TralfamadoreIII to inspect the ten million or more aliens he came across would surely look at the tadpole and cast it in with the fishes, and then put the frog somewhere completely different. They were different animals, with different body plans who lived in different ecosystems: how could they possibly have anything to do with each other?