Darwin and the Barnacle Read online

  DARWIN

  AND THE BARNACLE

  The story of one tiny creature

  and history’s most spectacular

  scientific breakthrough

  Rebecca Stott

  Mr Arthrobalanus

  SIMON CARNELL

  ‘Mr’ Arthrobalanus

  you’re an ill-formed monster

  with eyes in your stomach, binocular eyes.

  Distinctly deviant,

  you’re an angel

  dancing on the pinhead of yourself,

  fishing for food with your feet.

  Peered hard and long enough at,

  you’re a grain containing

  a strange new world.

  From your squatter’s nutshell

  the whole of creation

  is unfolding, like a dropped into water

  Japanese paper flower.

  Darwin and the Barnacle

  Contents

  Title Page

  Epigraph

  List of Illustrations

  Acknowledgements

  Preface

  1 The Sponge Doctor

  2 Riddles of the Rock Pools

  3 A Baron Münchausen Amongst Naturalists

  4 Settling Down

  5 Better Than Castle-Building

  6 Very Like a Lobster

  7 On Speculating

  8 Writing Annie

  9 Corked and Bladdered Up

  10 Drawing the Line

  11 Manoeuvres and Skirmishes

  12 The Universe in a Barnacle Shell

  Epigraph: The Asphalt Curtain

  Bibliography

  Index

  About the Author

  Copyright

  List of Illustrations

  1 A Cross-section of the Acorn Barnacle

  Darwin, C., Plate 25, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1854)

  2 A Cross-section of the Stalked Barnacle (Anelasma: Ibla)

  Darwin, C., Plate 4, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1851)

  3 Robert Grant

  The Wellcome Library, London

  4 Leith Races

  City Art Centre: City of Edinburgh Museums and Galleries

  5 Leith Pier and Harbour, 1798

  Grant, J., Old and New Edinburgh: Its History, Its People and Its Places, vol. 3 (London, Paris and Melbourne: Cassell and Company, 1887), p. 272. From a drawing by J. Waddell.

  6 Darwin’s Colour Chart

  From Syme, P. ed., Werner’s Nomenclature of colours with Additions, 2nd ed. (Edinburgh and London: William Blackwood and T. Cadell, 1821)

  7 Botofogo Bay

  From Caldcleugh, A., Travels in South America (London, 1825)

  8 Repairing the Beagle

  The Wellcome Library, London

  9 Down House

  Engraving of Down House, The Century Magazine, 1883

  10 Darwin’s study

  English Heritage Photo Library

  11 Charles Darwin with his son William, 1842

  University College London Library Services, Galton Papers, 9

  12 Mr Arthrobalanus

  Darwin, C., Plate 23, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1854)

  13 Emma Darwin with her son Leonard

  H. Litchfield, Emma Darwin wife of Charles Darwin: A Century of Family Letters, vol. 2, (Cambridge, 1904), p.168. Original photograph by Maull and Fox

  14 Ibla: Scalpellum

  Darwin, C., Plate 5, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1851)

  15 Annie Darwin

  The English Heritage Photo Library

  16 The Wet Sheet

  The Wellcome Library, London

  17 Dr Gully

  Worcester County Council Cultural Service, Malvern

  18 Douche

  The Wellcome Library, London

  19 Joseph Hooker

  The Linnaean Society of London

  20 Microscope

  Beck, R. (1865), A Treatise on the Construction, &c of Smith, Beck and Beck’s Achromatic Microscopes, London: John Van Voorst, p. 102

  21 Darwin’s Memorial of Annie

  The Syndics of Cambridge University Library

  22 Interior of The Crystal Palace

  The Dickinson Brothers (1854), Dickinson’s Comprehensive Pictures of the Great Exhibition of 1851, vol. 1, (London: Dickinson Brothers – Her Majesty’s Publishers). Frontispiece to The Transept. Original paintings by Messrs Naah, Haghe and Roberts, R.A.

  23 Royal Polytechnic Institution

  Guildhall Library, Corporation of London

  24 The Outside of a Stalked Barnacle

  Darwin, C., Plate 7, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1851)

  25 Thomas Huxley

  Frontispiece to vol. 2 of Huxley, L., ed., Life and Letters of Thomas Henry Huxley, (London: Macmillan, 1903). Original photograph by Maull and Polyblank, 1857

  26 The Allied Camp on the plateau before Sebastopol

  Detail from photograph by Roger Fenton, The Central Library, Birmingham

  27 The Outside of an Acorn Barnacle

  Darwin, C., Plate 1, A Monograph of the Sub-Class Cirripedia, with figures of all the Species (Ray Society, 1854)

  28 ‘Common Objects at the Seaside’

  John Leech’s cartoon in Punch, London, 1857

  29 ‘Valuable Addition to the Aquarium’

  Drawing room aquaria as illustrated by John Swain in Punch, London, 1860

  30 The Spirit Store

  Courtesy of University Museum of Zoology, Cambridge; photographed by Yvonne Barnett

  31 Darwin’s barnacles – microscope specimens

  Courtesy of University Museum of Zoology, Cambridge; photographed by Yvonne Barnett

  32 Microscopic image of the remains of Darwin’s

  Mr Arthrobalanus (Cryptophialus minutus)

  Courtesy of Professor Michael Akam, FRS, University Museum of Zoology, Cambridge

  Acknowledgements

  Books and ideas grow in conversation and correspondence. The majority of such conversations took place for this book around a large oak table in a seminar room in Darwin College, Cambridge. Here a collection of postgraduates, researchers, writers and academics from widely diverse subjects and disciplines met every fortnight or so for a year to discuss the MS of Darwin and the Barnacle as it was being written. To these people I am especially grateful. They include many people from the vibrant History and Philosophy of Science Department of Cambridge University: Jim Secord, Anne Secord, Jim Moore, Patricia Fara, Jim Endersby, Sujit Sivasundaram and Steve Ruskin; from the Cambridge English Faculty, Liz Hodge and David Clifford; from the Cambridge Faculty of Divinity, Thomas Dixon; from the Darwin Correspondence Project, Paul White and Shelley Innes, and Adrian Friday from the Cambridge Zoology Museum.

  The book would not have been written without the resources provided by the Cambridge University Library and by the Darwin Correspondence Project. I owe a debt of gratitude for the generosity and support of the distinguished Darwin scholars James Moore, Adrian Desmond and Randal Keynes.

  Few historians of science have had the patience or zoological understanding to have made a specialism of Darwin’s barnacle work. I am indebted to those who have, particularly Marsha Richmond Shelley White, Phillip Sloan, Alan Love, Bill Newman, D.J. Crisp and A.J. Southward.

  Adrian Friday and Prof. Michael Akam gave their time and attention to capturing the remains of Mr Arthrobalanus’ dissected body on film. Simon Carnell turned that same body into poetry to form the exquisite epigraph to this book.

  A
t Faber, Julian Loose, Nick Lowndes and Angus Cargill provided intelligent, astute and tough editorial advice as well as meticulous care and attention to detail.

  Faith Evans, my literary agent, continues to be a constant inspiration.

  Three talented undergraduates from the APU English Department helped in the final editorial stages of the book: Sian Mansfield, Catherine Grant and Alison Smith.

  I am also grateful to other richly perceptive readers who have helped shape the book in different ways: special thanks to the remarkable biographer Sally Cline and also to Paul Morrish, James Burgess, Tory Young, Jonathan Burt and Mark Currie. And finally to my son, Jacob, who observed, after I had described the book in the making, that I seemed to have a special fascination with making big things out of little things. So, I explained, did Darwin.

  Preface

  The rocks between tide and tide were submarine gardens of a beauty that seemed often to be fabulous, and was positively delusive, since, if we delicately lifted the weed-curtains of a windless pool, though we might for a moment see its sides and floor paven with living blossoms, ivory-white, rosy-red, orange and amethyst, yet all that panoply would melt away, furled into the hollow rock, if we so much as dropped a pebble in to disturb the magic dream.

  Edmund Gosse, Father and Son

  In the summer, my brothers, sister and I lived on the beach at the bottom of our terraced street, foraging, poking about in rock pools, making sandcastles or stone dams, levering shells off rocks to find sea creatures: creatures for dreams and for nightmares. We were always barefoot and the soles of our feet soon hardened to the sharp impress of the acorn barnacle shells that covered every surface below the tide line, millions of white cones – little volcanoes we called them – all different sizes growing over and under and on each other, competing for space, on rocks, on the wooden breakwater, on shells and driftwood. Five heads pressed together, ten feet waving in the air, our bellies on the warm sand, we’d drop a rock or a shell covered in the white cones into a bucket of sea water and wait. First, a tiny hatch opened at the top of each cone. Then a few seconds later, long, feather-like fans unfurled through the hole and began snatching at the water, rhythmically, like a pulse or a heart beat, all together. If we could have made the cone house invisible we would have seen its bizarre inhabitant, a cream-coloured shrimp-like creature, upside down, glued to the rock by its head, fishing for plankton through the hole in its cone with its feathery feet.

  1 A Cross-section of the Acorn Barnacle

  Barnacles take two principal shapes: the coned seashore barnacles and the stalked barnacles that cluster on driftwood. As a child I saw the stalked kind for the first time behind glass, not in an aquarium or a museum but in my grandfather’s wholesale food warehouse. His father had been a ship’s chandler on the east coast of Scotland, but the family business had moved south and was now supplying food to the restaurants and hotels of the south of England. The dimly lit, labyrinthine warehouse was another country: the smells of spices and oils, mountains of sugar and flour sacks, caves of bottled and tinned treasures, trapdoors, levers, pulleys and winches, a locked cold-room that poured out mist and in which hung the smoked carcasses of pigs.

  We played hide-and-seek here. One day, seeking a new hiding place, steeling myself against imagined ghosts, I took the little back stairs that creaked up through a trapdoor into a dusty sunlit attic where the boxes of exotic foreign food were kept in jars in stacked boxes: bottled snails, frogs’ legs, okra and caviar. That day there was a case I hadn’t seen before. It was marked Perceves: twelve catering jars of pickled stalked barnacles from Portugal in a box. They looked like clawed fingers on the other side of the glass jar, one-inch prehistoric monsters with stalks the colour of glistening black elephant skins and a claw like the beak of a bird. I couldn’t imagine how anyone could want to eat such things or how they would do so. Snails were bad enough. It made my flesh creep. Why had God made such creatures; what were they for?

  2 A Cross-section of the Stalked Barnacle (Anelasma: Ibla)

  Thirty years later, a Portuguese waitress in a seafood restaurant overlooking a harbour wall in Viana do Castelo showed me how to deftly twist barnacle stalk from claw and pull out the slither of pink flesh hidden inside the black stalk. It tasted of the sea – mysterious, briny and a little gritty, like mussel flesh. I opened up the beak-like end on my plate, to see the little black creature inside, curled upside down, its feathered feet retracted. In the sea it would be dancing like its coned cousins, unfurled amongst plankton. Now my questions were different: how had it come to this strange shape? How had it come to be through unimaginable centuries of metamorphosis? How had it evolved?

  By the time I ordered barnacles from the menu in Viana do Castelo, the bizarre creatures had become inseparable in my mind from Charles Darwin, for the great man, the author of one of the most groundbreaking books of all time, had also spent eight years collecting, dissecting, analysing and mapping barnacles. It was a passion – an obsession. It nearly killed him. But the final books, meticulously detailed, won him the Royal Society Medal in 1854 and established him as a scientist who had won his spurs. Without his barnacle spurs and barnacle contacts, On the Origin of Species by Natural Selection would have been very differently received.

  The barnacle obsession which dominated all Darwin’s waking hours between 1846 and 1854 began with a discovery made on the Beagle voyage.

  On a hot Chilean beach in January 1835 the twenty-four year-old Darwin picked up a conch shell covered in tiny holes, like lace, which he slipped into his pocket. Under the microscope in his Beagle cabin, with one of the holes illuminated by candlelight, he saw the squatter, the tiny cream-coloured curled creature that had dug the hole. What manner of beast was it? It looked for all the world like a barnacle, but Darwin knew that, according to the zoology text books, barnacles secrete their shelly homes; they don’t dig them. He teased out the creature from the base of the hole with a pin and then under the microscope examined its beautiful and complex anatomy. He checked the zoology books in the ship’s library just to be sure. It was indeed a barnacle anatomically, although there were unaccountable deviations from the barnacle’s archetypal norms. He didn’t know it at this point, but this barnacle, soon to be nicknamed Mr Arthrobalanus, would not be finished with him for a further twenty years. This was an encounter on a beach with a creature too small to see with the naked eye that would lead to eight years of meticulous dissection and observation of every known barnacle – fossil and living – in the world and to four published volumes with hundreds of pages of analysis.

  Darwin was lucky. The barnacle he had found on the South American beach, with no cone-house or stalk, was an extremely rare form of burrowing barnacle. This squatter was highly unusual, an aberrant, because up until 1830 barnacles had been defined by the shape of their shell-houses not their soft bodies, and this one had no house of its own. For Darwin, anomalies like these raised all sorts of questions about the classification systems themselves. What makes a barnacle a barnacle? And when there is so much variation within a group like the barnacle – in terms of size, method of reproduction and life cycle – what common features hold the family together? His Chilean anomaly would help to explain barnacle evolution and adaptation.

  Barnacles had colonised the shorelines, ships’ hulls and seabeds of the temperate world. They were ubiquitous. Yet they were as complex and unmapped as the Amazonian rainforest. No one had mapped the barnacle. Darwin would be the first to do so. It would be an evolutionary classification showing how, from a common ancestor, hundreds of different and spectacular barnacle adaptations had taken place over millions of years.

  Darwin carried 1,529 species bottled in wine spirits back on the Beagle to London in 1836. Amongst these was a single bottle containing a dozen or so very rare minute South American barnacles, teased out from a conch shell and labelled Balanidae. He didn’t understand them yet, but he would come back to them later. The barnacle was unfinished business.

 
By 1844, when he was thirty-five, Darwin had formulated and sketched out his species theory in essay form – the incendiary ideas that would change human understanding of time and nature for ever. He had sealed this essay in an envelope, locked it away in a drawer in his study and put together a set of instructions to his wife on how to handle its publication in the event of his death. He now needed to flesh out the theory with evidence and careful rhetoric but, instead of doing this, he turned to the barnacle in the bottle on his study shelf – the riddle that needed to be unlocked. It would take him a month or so to solve it, he thought, and then he would complete and publish the species theory.

  The baffling, ‘illformed’ creature he had found in the conch shell was the size of a pin, he remembered. It fitted barnacle body plans in some ways but was completely deviant in others. The more Darwin studied this creature, the more bizarre it appeared to be. How had it come to be this way? How did it fit into the barnacle order? Who were its near relatives?

  Within days, Darwin realized that there was no way he could understand just how divergent his Chilean barnacle was until he had seen and mapped most if not all of the hundreds of varieties of barnacles clustered on rock pools, seabeds, driftwood and whale flanks around the world. He began to send for specimens, and once they began to arrive there was no going back; he was hooked. Two years later, his study piled high with barnacle specimens of all shapes and sizes labelled in pillboxes, he had committed himself to writing a definitive monograph. Slowly, he clawed his way back to the problem of the Chilean barnacle, now named Mr Arthrobalanus, via the microscopic examination of all the fossil and living barnacles in the world, nearly twenty years after the first encounter on the South American beach. From 1846 when he began, it took Darwin eight years to work out the riddle of Mr Arthrobalanus’s bizarre anatomy, years in which the species theory lay sealed in a drawer in his study – postponed. He was frustrated, confounded, but he couldn’t stop.