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  THE DARWIN DICTIONARY

  Charles Darwin understood that words matter, especially in science. Yes, no, true, false, experimental, hypothesis, theory, law, replicable, preliminary, maybe, not a chance—we use all of them to describe the various stages in scientific research from I think so to I was absolutely right.

  Darwin enriched the scientific vocabulary, giving new and wider meaning to words that describe newly discovered or rediscovered facts and, in some cases, fantasies.

  Atavism, from the Latin word atavus, meaning “ancestor,” defines a reversion to an earlier type. In biology, this means that an individual born today may arrive with a trait characteristic that disappeared from his species a long time ago. Atavisms may occur because the gene that triggered them remains dormant in the individual until other genes that suppress it are inactivated or, as noted in Chapter 5, the trait is artificially stimulated to produce, in one case, a chicken with teeth.

  Characters are characteristics. A derived character is a trait that has been modified. One example is the different shapes of various animal tails or their disappearance, as in the great apes who have no external tail vs. monkeys who have a very visible, very useful one. A primitive character is one that hasn’t changed very much over the generations, perhaps the structure of the human leg. A shared character is one that shows a relationship among individuals, for example, similar skin and hair color among human parents and siblings or groups of people. An example of an evolutionary shared character among various species is the similarity of the “walking limbs” of various mammals, most specifically the chimpanzees and humans. A synapomorphy is a shared, derived character.

  Evolution in biological terms is defined by the Oxford Dictionaries as “the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth.” The process may be governed by mutation, which produces a sudden unexpected change; natural selection, Darwin’s term for changes dictated by sexual choice of mates and adaptation to the environment; or by genetic drift, a process defined as occurring over time but not due to natural selection.

  Homology means similarity, in this case the similarity of characters showing a link between species such as the seven vestiges of an organ, even though it is completely superfluous, if that organ plays an important role in the other species of the same family. In his Philosophie Zoologique (1809), Jean-Baptiste Lamarck—the man who insisted that acquired characteristics such as a docked mouse’s tail could be passed along to the next generation—reprised Aristotle’s observations on life underground: “Olivier’s Spalax,” he wrote, “which lives underground like the mole, and is apparently exposed to daylight even less than the mole, has altogether lost the use of sight: so that it shows nothing more than vestiges of this organ.”5 But after Darwin, the word, or its noun form vestige, came to mean a body part the body does not need, a misunderstanding that has continued to color our own view of some of our body parts. Those Darwin considered vestigial may, like our body hair, be smaller or less visible than what our evolutionary ancestors had or, like a tail or a full third eyelid, never have been part of us or, like the appendix, play a role in a complex immune system that Darwin could not have envisioned. And sometimes what looks vestigial and useless has surprising virtues. Our ears may not normally rotate, turning in the direction of a sound, but even our truly rudimentary outer ear muscles have a purpose. Actually two purposes. First, they shape the folds of the rim of the ear and, second, for some lucky few who can control them, they offer a way to entertain at cocktail parties by wiggling the ear as cleverly as any dog or cat or horse or ape.

  1

  Hide & Seek

  The Appendix

  “With respect to the alimentary canal, I have met with an account of only a single rudiment, namely the vermiform appendage of the caecum…. Not only is it useless, but it is sometimes the cause of death …”

  —Charles Darwin, The Descent of Man (1871)

  “Its major importance would appear to be financial support of the surgical profession.”

  —Alfred Sherwood Romer and Thomas S. Parsons, The Vertebrate Body (1986)

  DID YOU SEE WHAT I SAW?

  The centuries-long attempt to find and then explain the appendix is a tale of anatomical hide-and-seek peopled with pioneering 19th- and 20th-century doctors such as:

  Sir Frederick Treves (1853–1923), the prominent Victorian surgeon perhaps best known for his friendship with and care of the “elephant man” Joseph Merrick and then as the man who relieved Queen Victoria’s “corpulent heir,” Edward VII, of his own troublesome appendix on the eve of his coronation (the coronation was postponed for two weeks)

  Charles McBurney (1845–1913), who pinpointed the exact location of a diseased appendix now known as “McBurney’s Point”

  Irish physician Denis Burkett (1911–1993), who popularized the idea that eating foods rich in dietary fiber might reduce the risk of appendicitis and colon cancer

  There are artists, including Leonardo da Vinci, who drew the first picture of an appendix, and a whole army of famous patients in addition to Churchill and the King, from (maybe) Hippocrates to (definitely) neurosurgeon Harvey Cushing and popstars Elton John, Lindsay Lohan, and Ted Turner. And, alas, there were the appendicitis deaths of famous folk such as Brigham Young in 1877. In 1902, there was Walter Reed, the U.S. Army physician who identified the mosquito as the source of yellow fever infection. Seven year later, appendicitis did in the artist of the American West, Frederic Remington. George Wesley Bellows, the painter and lithographer known for his expressive action portraits of American athletes, followed in 1925. Rudolph Valentino and Harry Houdini followed one year later. The lethal appendix made its way into books, onto the stage, and over the air. In Stephen King’s novel The Stand (1978), one man survives the apocalypse only to die of appendicitis. Onstage, young Wally Webb fell victim in Thorton Wilder’s drama Our Town (1938). In an episode of M*A*S*H* (“The Colonel’s Horse,” 1976), the person in pain is Hot Lips Margaret Houlihan; in 1977 on Laverne and Shirley, it’s Shirley; in 1989 on Doogie Howser, it’s Doogie Howser’s girlfriend; and in the fourth season of Lost, it’s Jack. For the kids, there are characters with appendicitis in the video games Trauma Center and Mega Man Battle Network, and for little girls who want to play doctor, there are Madeline dolls with appendicitis scars.1

  Back in Real Life, there are moments of medical fantasy such as the report that while on assignment in China in 1971, New York Times editor James Reston had his appendix removed with no anesthesia other than acupuncture. There is medical drama such as Russian doctor Leonid Rogozov’s developing appendicitis while on the sixth Soviet expedition to Antarctica in 1960–1961 and, being the only physician on base, operating on himself.2 Finally, there is this simple but compelling fact: the unassuming appendix played a leading role in the emergence of modern surgery when, after the introduction of anesthesia and antisepsis, the operation to remove it became the single most popular emergency surgical procedure in the world.

  The story begins with, of all things, Egyptian mummies.

  Although we are used to thinking of the word mummy as Egyptian, in fact it comes from the Arabic mumiyah meaning “body preserved by wax or bitumen.” That small detail aside, the ancient Egyptians really were far and away the best at preserving corpses, a skill arising naturally from their environment. Early on, during the Neolithic period3, the dead were buried in the hot dry desert sand which naturally dried and preserved them. A cooler but equally dry extreme European climate produced equally preserved mummies such as the “Iceman” whose shriveled frozen body was discovered in 1991, high on the Austrian-Italian border of the Alps, where he had perished an estimated 5,000 years before. Celtic mummies dating back to the Iron Age (400 BCE–400 CE), first uncovered in 1821 peat bogs whose acid had turned them dry and leathery. “Bog mummies” have also surfaced in Germany, The Netherlands, Poland, Sweden, and the United Kingdom.


  As civilization grew more sophisticated, the well-off and powerful began to inter their dead in tombs rather than hanging them out to dry. This meant that they needed to find a way to preserve the bodies that remained on view in the tombs. The solution: mummification by man rather than by environment. The world’s oldest mummies made by man may be those created by the Chinchorro on the west coast of South America and dating back to 7000 BCE, 4,000 years before the Egyptian mummies. More than 100 Chinchorro mummies have been recovered from the Atacama Desert of northern Chile and southern Peru and reside in the collection of the University of Tarapacá’s museum in Arica, Chile. (Unlike Egyptian mummies, which were laid on their backs after mummification, the Chinchorro stood theirs upright so the corpse’s mouth often fell open. The most famous picture of this may be Edvard Munch’s celebrated painting “The Scream,” reliably reputed to be based on a Peruvian mummy the artist saw in the Musée du Louvre.) 4, 5

  In Egypt, the process of artificially mummifying a body might last more than two months. Each step in preparing the body was the focus of religious ritual. The priests charged with the job—many of whom became doctors—began by inserting a long instrument through the nose to pull out the soft brain matter. Then they emptied the body cavity, tossing the organs into four covered jars or packets representing the four sons of Horus, the god of sky, war, and hunting. The jars or packets were entombed with the body, unless the organs were, as Plutarch wrote, discarded “as the cause of all the sins committed by man.”6, 7, 8 The embalmers then filled the empty human shell with “odoriferant, aromatic, and balsamic drugs, capable of arresting the progress of putrid decomposition” and put the corpse out to dry in the Mediterranean sun.9 Presto, change-o, mummies.

  The Chinchorro may have been first to mummify their relatives, but the first people to notice that we had an appendix seem to have been those Egyptian priests who named one of the sinful entrails—the appendix—“the worm of the intestine.” It was a lucky find because not every living body has one. Not even every mammal has one. Gorillas, chimps, and orangutans do. So do wombats, rabbits, rats, and some opossums. But cats and dogs, horses and cows and sheep and goats, fish and frogs and salamanders, lizards, snakes, and birds don’t. Neither do monkeys, an important point because both Aristotle and Galen dissected monkeys to produce the anatomical studies on which westerners relied for centuries.

  MUMMY MEDS

  A whole list of movies beginning with “The Mummy” (1911) starring William Garwood, “The Mummy” (1932) with Boris Karloff, and “The Mummy” (1999), the first in Brendan Frazer’s trilogy, have made mummies into scary creatures; but our steely Victorian forebearers regarded mummies as life savers. Like powdered unicorn horn, dried and powdered human mummy tissue known as mummia was believed to have “restorative powers,” often a more genteel way of saying, “treatment for erectile dysfunction.” The stuff was made presumably from mummies carted back to England from Egypt or, more likely, as the French barber surgeon Ambroise Paré wrote, it might have been “made in our France” from bodies stolen from the gallows. In his 1974 novel Monsieur, The Prince of Darkness, Lawrence Durrell draws the scene for us: “ ‘Now let us partake of the holy mummia,’ he said in commanding tones and the dervishes advanced towards us humbly bearing large silver trays on which were a number of small bowls with pieces of mummia–or at least I presumed it was mummia.”10, 11 There is no further information in the scene as to what was actually restored.

  For reasons both religious and cultural, the ancients, East and West, did not practice dissection. In the West, some speculate that Aristotle dissected in secret, but you would not know that from his writings, such as Parts of Animals (ca. 350 BCE), which are strictly about nonhuman bodies. In the next century, two Greek physicians, Herophilus (335–280 BCE) and Erasistratus (304–250 BCE), were given permission to dissect human cadavers at the anatomy school they founded in Alexandria. Three hundred years after that, the Greek-turned-Roman physician Claudius Galen (c. 129–c.216) was rumored, like Aristotle, to have performed secret dissection; but, like Aristotle, his anatomical drawings were based on animals, which meant that virtually nobody actually understood what a human skeleton or most human tissues and innards looked like. Consider the neck. Unlike ours, a dog’s shoulder bones are not connected; canines do not have the collar bone that reaches across the front of the top of the human torso. In addition, the muscles around our vertical backbone are connected differently than Fido’s around his horizontal spine. Add to that the fact that neither the ancient Chinese nor early Islamic physicians practiced human dissection, either, and you can understand why, except for those Egyptian mummy workers, no one had a chance to see the appendix.

  Eventually, of course, science crept into the picture. Christians formalized their opposition to dissection at the Council of Tours in 1163, but in 1492, just as Columbus sailed off to his New World, Leonardo da Vinci began to defy the Church ban on human dissection. He made anatomical drawings that, had they been published, would have introduced the appendix to the Old World. But it was one thing to do dissection quietly, and quite another to make the results public, so Leonardo’s drawings did not appear until after his death. Thus the prize for being first to describe the appendix in public is usually awarded to Italian anatomist Jacopo Berengario da Carpi of the University of Bologna, where, in January 1513, the Vatican approved the Italian physician Mondino de Luzzi’s bringing public dissection of human cadavers into his classes on anatomy. Twenty years later, while performing an autopsy, Carpi discovered an empty, small cavity at the end of the cecum and included it in his ground-breaking text, Anatomia Carpi (1535). After that, Andreas Vesalius, the founder of modern anatomy and the Belgian Imperial physician at the court of Charles V, included drawings of the appendix in De Humani Corporis Fabrica (1543). His book was a classic, but his anatomy acumen was not. He grouped the appendix together with the ileum and the colon as one of the three openings of the cecum, a pouch at the junction of the small and large intestines.

  The Human Intestines, with the Appendix

  The Egyptians had called the appendix “the worm of the intestines.” Leonardo thought it looked like a little ear, so he called it orecchio. Carpi, ignoring both, chose the name addentramentum, from the Latin ad- meaning near, intra meaning inside something, and -mentum meaning medium or result of. The switch back to “worm-shape” (vermiformis) has many supposed fathers including Philip Verheyen, a Flemish physician so intrigued by anatomy that when his own leg was amputated in 1675, he injected it with a mixture of waxes and fragrant oil and preserved it either in balsamic vinegar or brandy and black pepper. Then he dissected the leg bit by bit in search of the source of his discomfort; instead, he discovered a tissue at the back of the heel that he christened chorda Achillis (Achilles tendon). In 1710, having moved back up and into the body, he is reputed to have rechristened the appendix “the appendix.”

  Earliest-known drawing of the appendix, Leonardo da Vinci (1492)

  FALSE DIAGNOSES & FAVORED FOLK REMEDIES

  Simply put, the appendix is, as its name implies, an appendage, a small, closed tube attached to the cecum. An adult human appendix is about the size of a finger, 6 to 8 centimeters (2.4 to 3.1 inches) long and slightly less than one-half inch around. Like other body parts, its size may vary from person to person. In 2004, The Guinness Book of Records listed as the world’s champion the 8.26-inch appendix extricated from a twenty-six-year-old man at Lister Hospital in Herefordshire, England. Two years later, the new champion was a 10.24 inch appendix removed during autopsy on a Croatian man at the Ljudevit Jurak University Department of Pathology in Zagreb, a record broken in 2011, when a team of Egyptian and Qatari surgeons reported removing a 21.6-inch appendix from a thirteen-year-old boy.12

  Like the rest of the intestines, the appendix has several layers of tissue: a mucosa (thin lining with overlying mucus), a sub-mucosa (connective tissue and immune cells) covering a muscular layer, and an external membrane (serosa) such as the one tha
t covers the entire contents of the abdomen. The appendix is filled with glands that secrete mucus and fluids. Its blood supply arrives via a branch off the aorta called the superior mesenteric artery and flows away into the superior mesenteric vein. The same nerves that reach the rest of the gut come here, and the appendix is full of lymph tissue, which means that, like the equally underappreciated tonsils, it appears to be part of your immune system.

  In 1859, when Charles Darwin labeled the appendix rudimentary, and his contemporaries translated that into useless, nobody even knew we had an immune system, which wasn’t identified until around 1908. They also didn’t know about or have:

  • A detailed anatomy of “the worm” and what (if anything) it might do

  • A list of the creatures that had an appendix and those that didn’t

  • Knowledge of the link between a high white cell count and an infection (c.1840s–1850)

  • Anesthesia (1846), antisepsis (1867), and antibiotics (1936)

  • Diagnostic imaging such as X-rays (1895), ultrasound (1957) and MRIs (1977)

  • A laparoscope (1916) or a computer chip television camera laparoscope (1986)

  Which didn’t really matter until something went wrong.

  FROM NEEDLE TO KNIFE