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  Praise for Carol Ann Rinzler’s Previous Works

  “Our reviewer declared that this book represents some of the best writing about science for the nonscientist that he has encountered in recent years.”

  —American Association for the Advancement of Science

  “Rinzler clearly enjoyed researching her subject and can’t stop herself from going on interesting digressions, often bringing up one or two mostly unrelated topics within the course of a paragraph. She’s at her best when discussing medical history and etymology.”

  —Library Journal

  “Stylish, informative, entertaining, and pleasantly personal … maintains a fascinating perspective on the peculiarities of being human.”

  —Rain Taxi Review of Books

  “Readers often like to walk away from a book feeling they learned something—that the author left them with a new way to look at an old idea, and this book fulfills that need.”

  —City Book Review/San Francisco & Sacramento

  Copyright © 2017 by Carol Ann Rinzler

  All rights reserved. No part of this book may be reproduced in any manner without the express written consent of the publisher, except in the case of brief excerpts in critical reviews or articles. All inquiries should be addressed to Skyhorse Publishing, 307 West 36th Street, 11th Floor, New York, NY 10018.

  Skyhorse Publishing books may be purchased in bulk at special discounts for sales promotion, corporate gifts, fund-raising, or educational purposes. Special editions can also be created to specifications. For details, contact the Special Sales Department, Skyhorse Publishing, 307 West 36th Street, 11th Floor, New York, NY 10018 or [email protected].

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  10 9 8 7 6 5 4 3 2 1

  Library of Congress Cataloging-in-Publication Data is available on file.

  Cover design by Rain Saukas

  Cover images: iStock

  Print ISBN: 978-1-5107-1250-8

  Ebook ISBN: 978-1-5107-1251-5

  Printed in the United States of America

  For my resolute agent

  Phyllis Westberg,

  My creative editor

  Michael Lewis,

  and

  For my husband

  Perry Luntz

  Always

  Table of Contents

  Introduction

  Where in the World Was Charles Robert Darwin?

  The Darwin Dictionary

  1. HIDE & SEEK

  The Appendix

  Did You See What I Saw?

  Mummy Meds

  False Diagnoses & Favored Folk Remedies

  From Needle to Knife.

  Sir Winston’s Triple Complaint

  Form Follows Function.

  After Words.

  The Appendix.

  2. FEATHERS & FUR

  Body Hair

  The Natural Nature of Our Hair.

  The Tree of Human Life

  Hair & Fur & Feathers

  How We Lost Our Hair

  Hair on Top

  The Price of Male Facial Hair

  Hair in the Middle

  Hair Down There

  Less Hair but Not Hair-less

  3. THE TALE OF THE TAILBONE

  The Coccyx

  The Incredible Versatile Tail

  Fascinating Far End Factoid

  Getting By with No Tail at All

  The Man Who Invented the Human Tail

  Defects Associated with “Human Tail”

  At the Tail End

  Flowers & Funnies & Men with Tails

  4. EAR RINGS

  The Auricular Muscles

  Breathing Through Your Ears

  How We Hear.

  Smelly Ears = Smelly Armpits

  Picturing the Pinna.

  Muscle Mechanics.

  5. BLINK!

  The Third Eyelid

  What Richard Owen Wrote

  Looking through the Lid

  What You See Is What We’ve Got

  The Human Eye Unmasked

  The Very Human Version of a Third Eyelid.

  Two Eyes. Four Lids. What Could Possibly Go Wrong?

  Eyelids of the World

  6. PEARLY WHITES

  Wisdom Teeth

  Fish Teeth & Darwin’s Finch

  How Old Is Your Eon?

  Missing Bone & Surplus Molars

  Building & Keeping Human Teeth

  The Last Bite.

  Name That Tooth.

  7. DISPENSABLES

  The One and Only Brain

  Replaceable/Remediable

  Transplantation Waiting List, United States, 12:14 PM, April 26, 2016

  (Almost) Reliably Redundant

  Useful but Dispensable

  Four (Really Pretty Much) Useless Human Body Parts

  One Indisputably Vestigial Organ

  8. FUTURE MAN

  Yes. No. Maybe.

  The End of Evolution

  The Next Evolution

  Man Improving Man

  Infant Mortality in the United States, 2010

  Life Expectancy at Birth in the United States, 1900–2010

  Fictional Futures.

  Future Films

  The Rise of Mr. Robot

  9. POSTSCRIPT

  The Darwin Family Business

  Development in Dress by George Herbert Darwin

  About the Author

  Endnotes

  Index

  Illustrations

  Chapter 1:

  • The Human Intestines, with the Appendix (1a) [Public domain, courtesy of Indolences at the Wikipedia project]

  • Earliest-known drawing of the appendix, Leonardo da Vinci (1492) (1b) [Public domain]

  Chapter 2:

  • Human Body Hair [Wikimedia Commons, under the terms of GNU Free Documentation License]

  Chapter 3:

  • The Greek & Roman Sea God Triton, Son of Poseidon/Neptune (3a) [Public domain; Wikipedia]

  • The Similarity among Embryos Illustration from Ernst Heackel’s Anthropogenie (1874) (3b) (Wikipedia)

  Chapter 4:

  • The Three-Part Ear, Gray’s Anatomy (4a) [Public domain; Wikimedia commons]

  • The Outer Ear, Gray’s Anatomy (4b) [Public domain; Wikimedia commons]

  Chapter 5:

  • The Human Plica Semilunaris Henry Gray, Anatomy of the Human Body [Public domain; Wikimedia commons]

  Chapter 6:

  • Your Canine Teeth (6a), Gray’s Anatomy [Public domain; Wikimedia commons]

  • Your Canine Teeth (6b), Gray’s Anatomy [Public domain; Wikimedia commons]

  Introduction

  “I have been speculating last night what makes a man a discoverer of undiscovered things; and a most perplexing problem it is.”

  —Charles Darwin, A Century of Family Letters, 1792-18961 (ed. John Murray)

  Tucked away near the end of Chapter 13 in Charles Darwin’s first edition of On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life (1859) is a quiet little list of “rudimentary, atrophied or aborted” body parts, evidence, perhaps, of how some animals and plants evolved: teeth in embryonic whales, wings for flightless birds, and undeveloped pistils (the female part of a flower) in male flowers. The only human tissue on the list is the mammalian male breast. Twelve years later, in The Descent of Man, and Selection in Relation to Sex (1873), Darwin added six bits and pieces of our bodies: The appendix, our body hair, the coccyx, our outer ear muscles, our “third” eyelid, and our wisdom teeth.

  After that, the race was on to identify unnecessary
tissues and organs. By 1893, when German anatomist Robert Wiedersheim published The Structure of Man: An Index to His Past History, he listed a grand total of 86 vestiges, organs once more important to the human body than they presently are. His list included (but was not limited to) valves in veins, the pineal gland, the lachrymal glands, the thymus, the thyroid, a clutch of small bones in the third, fourth, and pinky toes, and, in the full flower of Victorian prudery, the clitoris.

  But conclusion jumping is a dangerous sport. In 1859, Charles Darwin labeled the appendix “vestigial,” and ever since then people have translated that as “useless.” Contrary to common wisdom, the appendix has been pivotal in the history of medicine. First seen by ancient Egyptian priests preparing the dead, the appendix remained hidden from western eyes for several thousand years, emerging only when autopsy became common and Italian Renaissance artists and anatomists defied the Church prohibition on human dissection to discover what Leonardo da Vinci called the “little ear” at the junction between the small and large intestine. Once identified, the appendix played a leading role in the development of surgical medicine at the end of the 19th century. Today it figures in our exploration of the gastrointestinal system and our immune function, while pragmatic surgeons have used it to replace a damaged ureter.

  There are similar facts attesting to the value of Darwin’s earlier list of unnecessary body parts. A full set of toes keeps us balanced on our feet. The valves in our veins keep blood from flowing backward. And who doesn’t value our hormone-secreting thymus and thyroid, the lachrymal glands that moisten our eyes, and, thanks to Masters, Johnson, and sexually active women, the clitoris?

  Nonetheless, the Darwin Six still fascinate.

  From the start, Darwin’s theories and his list of vestiges prompted a passionate debate between strict creationists, who argued that the Designer created the world, from poppies to people, exactly as it is (or was in 1859) and religious liberals, who accepted physical adaptation as part of a Creator’s plan. The two sides met famously on June 30, 1860, at the Oxford University Museum, when Oxford Archbishop Samuel Wilberforce reputedly demanded of British biologist/anatomist Thomas Huxley whether he was descended from an ape on his grandmother’s or grandfather’s side. “If the question is put to me whether I would rather have a miserable ape for a grandfather or a man highly endowed by nature and possessed of great means of influence and yet employs these faculties and that influence for the mere purpose of introducing ridicule into a grave scientific discussion,” Huxley is reported to have said, “I unhesitatingly affirm my preference for the ape.”2

  There is some dispute about exactly who said what to whom that evening, but there is no doubt that Darwin the scientist sided with Huxley. Before his marriage, he confided to his prospective bride Emma Wedgewood that “he was in the process of rewriting the history of life. That, according to his convictions, all living things descended from a common ancestor. And that species were not to be attributed to God’s endless creativity, but were the product of a blind, mechanical process that altered them over the course of millions of years.” Emma’s reaction was to implore her betrothed to reread his Bible; she feared his unbelief might separate them in the life after death. Charles did not change his mind. However, Emma’s reaction showed him how difficult it was to convince other people of his ideas: the criticism would be devastating were he to publish his theories without adequate proof; and his scientific career would be ruined.3

  That proof had begun with Leonardo da Vinci and Michelangelo. Once they and others as adventurous as they decided to ignore the dictates of the Church and begin to dissect human corpses, the discovery and proper identification of human body parts, hidden and otherwise, were inevitable. It is foolish to suggest that we know everything about anything, including the structure of the human body. In reality, though, we are certainly close, so close that in August 2013 when a Belgian orthopedic surgeon announced that he had discovered a new ligament in the human knee, others were quick to point out that the “pearly, resistant, fibrous” tissue in question was first found by French surgeon Paul Segond in 1879.4

  What remains mysterious about the Darwin Six is function. For example, recent studies suggest the appendix plays a role in our immune system, raising once again the essential question of vestigiality—and for some the equally essential question of who created man and all his parts. But not every question has just one answer. Consider both the similarities and variations among those from whom we separated on the climb up the ladder to sapiens. And then consider this: in the Darwin debate, there is, as this proposal suggests, evidence to support whichever side you choose.

  Now, fair warning: I admit it. I love research. After all, what’s more satisfying than ferreting out the odd facts that hang off an individual’s character or life, or define an event or a condition, and then sharing what you’ve discovered? Etymology is one perfect example, so throughout this book you will find words that may (or may not) be unfamiliar to you, traced back to their (usually) Greek or Latin origins, thanks either to the delightful Etymology Online Dictionary at http://etymonline.com/index.php or my own 16-pound 1941 edition of Webster’s New International Dictionary of the English Language. When possible, I like to include a person’s birth and death dates, to place him or her in history.

  I also delight in diversions, the literary sideways and byways down whose paths we may travel thanks to the oddity of the subject at hand. For example:

  • Examining the appendix tells a story of evolution, not just of man, but of medical thought and practice.

  • Considering our body hair leads to pictures at an exhibition, in this case, Gustave Courbet’s L’Origine du Monde at the Musée D’Orsay in Paris, where it is still stirring interesting emotions; and then to dinner, where, before you carve the chicken, you might consider how similar its hemoglobin is to yours.

  • Talking of tails invites quotes from two fantastical literary sources, George Orwell’s Animal Farm and an essay establishing the relationship between the peacock’s tail and male fashion as envisioned not by Charles Darwin, but by his fifth child and second son, George Howard, whose imaginative response to his father’s discoveries is available in full in Chapter 9: Postscript.

  • Exploring the muscles of the human ear presents the opportunity for a side trip to the anatomy of the Old World and New World monkeys, as well as to a charming 19th Century poem celebrating how we hear what we hear.

  • Viewing the history of the third eyelid includes a glance through the stats of the surprisingly illuminating science of eyeblinks.

  • Evaluating the value of wisdom teeth leads quite naturally to a list of the eras, periods, and epochs of life on earth that make it possible for us to pinpoint the moment when crocodiles kept their teeth but their avian cousins lost theirs.

  Not everyone shares my pleasure in off-road exploration, so when the diversion is more diversionary than usual, I have put it either into a sidebar or an endnote, thus preserving the flow of the text. Of course, you are free to skip directly from the first paragraphs of each chapter to the conclusion on the last page, a fast (but incomplete) explanation of why the part in question, which Darwin considered extraneous, may not be so.

  Now, a word about sources, primary where available, secondary when applicable, and Wikipedia more often than I would have thought likely. This last, a repository of all information, past, present, and future, has come a long way since its somewhat shaky beginnings. Today, it is surprisingly complete and surprisingly accurate, as well. For those who doubt, I suggest you bookmark this page, then turn straight to Chapter 5 and run your finger down the pages until you come to the endnote for “stye,” at which point I will rest my case. And, yes, all Internet sources cited in this book were active when referenced in 2016.

  Finally, if there is a lesson to be learned from Darwin, it is not that we are impressively different from our earlier selves, or more appropriately, our primate relatives, but that we have so much in common. In the 19th
century, as man began scientifically to separate himself from other animals and sometimes ignorantly from other “lesser” men, Darwin’s discoveries led to a reevaluation of our bodies that was at once innovative and premature. Lacking the tools with which to truly examine the human framework, he and his colleagues relied on what they were able to see on or just under the surface. Generally, that served them well enough, but if Charles Darwin were alive today, there is no doubt that like so many scientists before and since he would modify his views, which in this case means reconsidering which parts of us are and aren’t useful.

  As a writer specializing in medical issues, I came to Darwin as an inquisitive amateur, at first a fan intrigued by his negative view of the appendix and, then, inevitably, a devotee of this extraordinary man whose brilliance in discovering the origins of man is beyond dispute. But even heroes must, as the saying goes, put their pants on one leg at a time. Time has moved on to expand our understanding of the world outside and inside ourselves, so I believe that in our 21st century, Charles Darwin would accept as I do the words of one of my favorite doctors, Mark Pochapin, who runs the Division of Gastroenterology at NYU Langone Medical Center and has seen many an appendix in his time: “The human body is so marvelous that nothing is there by accident.”

  WHERE IN THE WORLD WAS CHARLES ROBERT DARWIN?

  If you know the name Charles Darwin you are also likely to have heard of the Galapagos, officially Archipiélago de Colón, the islands whose inhabitants, particularly its finch-like birds, stimulated and enhanced Darwin’s explorations into evolution. But do you know exactly where one sails to find this archipelago of 18 small volcanically formed islands spanning the equator 563 miles west of Ecuador, which governs them? Do you know their names, which are, in alphabetical order, Baltra, Bartolomé, Darwin, Española, Fernandina, Floreana, Genovesa, Isabela, Marchena, Pinta, Pinzón Rábida, San Cristóbal, Santa Cruz, Santa Fe, Santiago, Seymour Norte, Pinzón, and Wolf? Do you know that in 1979 the Galapagos Islands were named a UNESCO World Heritage Site? Maybe not. But what you do know for sure is: wherever you are is the center of your own world, Wikipedia has a map that is a perfect picture of Darwin’s destination. You will find it at http://schools-wikipedia.org/images/839/83989.png.htm, where, right before your eyes, the white dot west of Ecuador shows the islands appropriately in the center of the Western Hemisphere and, of course, in the center of Darwin’s revolutionary theory of where we came from and how we got from there to here.