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The Walking Whales The Walking Whales From Land to Water in Eight Million Years J. G. M. “Hans” Thewissen with illustrations by Jacqueline Dillard university of california press The Walking Whales The Walking Whales From Land to Water in Eight Million Years J. G. M. “Hans” Thewissen with illustrations by Jacqueline Dillard university of california press University of California Press, one of the most distinguished university presses in the United States, enriches lives around the world by advancing scholarship in the humanities, social sciences, and natural sciences. Its activities are supported by the UC Press Foundation and by philanthropic contributions from individuals and institutions. For more information, visit www.ucpress.edu. University of California Press Oakland, California © 2014 by The Regents of the University of California Library of Congress Cataloging-in-Publication Data Thewissen, J. G. M., author. The walking whales : from land to water in eight million years / J.G.M. Thewissen ; with illustrations by Jacqueline Dillard. pages cm Includes bibliographical references and index. isbn 978-0-520-27706-9 (cloth : alk. paper)— isbn 978-0-520-95941-5 (e-book) 1. Whales, Fossil—Pakistan. 2. Whales, Fossil—India. 3. Whales—Evolution. 4. Paleontology—Pakistan. 5. Paleontology—India. I. Title. QE882.C5T484 2015 569′.5—dc23 2014003531 Printed in China 23 22 21 20 19 18 17 16 15 14 10 9 8 7 6 5 4 3 2 1 The paper used in this publication meets the minimum requirements of ansi/niso z39.48–1992 (r 2002) (Permanence of Paper). Cover illustration (clockwise from top right): Basilosaurus, Ambulocetus, Indohyus, Pakicetus, and Kutchicetus. These are the animals that show that whales once had land-living ancestors. The background of this painting is a composite: these animals did not live in the same habitat or the at the same time. This book is dedicated to all the students, postdocs, fossil preparators, and technicians who worked in my lab and made this journey scientifi cally exciting as well as fun, in chronological order: Sandy, Ellen, Tony, Mary, Lauren, Mary Elizabeth, Amy, Lisa, Brooke, Sirpa, Rick, Bobbi Jo, Meghan, Sharon, Jenny, Denise, Summer, and Ashley. And it is dedicated to Elizabeth, for her encouragement. And it is dedicated to my mother, who supported everything I did enthusiastically. Contents 1. A Wasted Dig 1 Fossils and War 1 A Whale Ear 4 2. Fish, Mammal, or Dinosaur? 9 The King Lizard of Cape Cod 9 Basilosaurid Whales* 17 Basilosaurids and Evolution 33 3. A Whale with Legs 35 The Black and White Hills 35 A Walking Whale 41 4. Learning to Swim 51 Meeting the Killer Whale 51 From Dog-Paddle to Torpedo 52 Ambulocetid Whales* 58 Ambulocetus and Evolution 65 5. When the Mountains Grew 67 The High Himalayas 67 Kidnapping in the Hills 75 Indian Whales 78 viii | Contents 6. Passage to India 79 Stranded in Delhi 79 Whales in the Desert 85 A 150-Pound Skull 87 7. A Trip to the Beach 93 The Outer Banks 93 A Fossilized Coast 96 8. The Otter Whale 99 The Whale with No Hands 99 Remingtonocetid Whales* 109 Building a Beast out of Bones 116 9. The Ocean Is a Desert 117 Forensic Paleontology 117 Drinking and Peeing 120 Fossilized Drinking Behavior 121 Walking with Ambulocetus 124 10. The Skeleton Puzzle 127 If Looks Could Kill 127 How Many Bones Make a Skeleton? 129 Finding Whales’ Sisters 132 11. The River Whales 137 Hearing in Whales 137 Pakicetid Whales* 144 September 11, 2001 154 12. Whales Conquer the World 157 A Molecular SINE 157 The Black Whale 160 Protocetid Whales* 163 Protocetids and History 171 13. From Embryos to Evolution 173 A Dolphin with Legs 173 The Marine Park at Taiji 175 Contents | ix Shedding Limbs 177 Whaling in Taiji 187 14. Before Whales 191 The Widow’s Fossils 191 The Ancestors of Whales 198 Indohyus* 199 A Trust for Fossils 206 15. The Way Forward 207 The Big Question 207 Tooth Development 209 Baleen as Teeth 211 Notes 213 Index 233 *These six headings summarize the biology of the six fossil groups that form the tran- sition between whales and their terrestrial ancestors. Their relationships to each other and to the living families of cetaceans (whales, dolphins, and porpoises) are given in fi gure 66. Chapter 1 A Wasted Dig fossils and war Punjab, Pakistan, January 1991.â I am excited beyond belief! The National Geographic Society is giving me money to collect fossils in Pakistan: my very own field project, the first time ever. For years, it has been great to collect fossils in exotic places—Wyoming, Sardinia, and Colombia. But this is different. Now I can run my own program, decide where to collect, and study what is found. It’s exciting but also daunt- ing. My friend Andres Aslan will come with me. We’re perfect comple- ments: he loves geology and I love fossils. We’re both just out of school, freshly minted PhDs, and together we’re ready and able to set the world on fire, or at least vacuum up any fossil between Attock and Islamabad. It is Andres’s first trip to Pakistan. I first went there as a paleontology student in 1985, during the Soviet occupation of Afghanistan, when the CIA channeled much of its support against the Soviets through Paki- stan. Trucks full of equipment would travel the highway, the Grand Trunk Road, from Islamabad to the Afghan border at night—the very same road we took to our field area. The Soviet-backed Afghan govern- ment retaliated by trying to disturb the stability of Pakistan. Car bombs were the weapon of choice, and my hotel room in Islamabad offered an excellent view into the courtyard of the police station next door, where a line of charred, exploded mini-busses were evidence of their success. With mirrors tied to long poles, the police stopped every vehicle enter- ing the city and checked the underside for bombs. This didn’t bother me, 1 2 | Chapter 1 figure 1. Map of northern Pakistan and India, with places mentioned in this book. Fossil localities are indicated by bones (see also figure 22). as long as I could collect fossils, studying life from a very exciting period in earth’s history, fifty million years ago. Now, six years later, Andres and I arrive in Pakistan just before the New Year and receive our permits to work in the Kala Chitta Hills, west toward the Afghan border (figure 1). The television in our Islamabad hotel is showing CNN stories about the Iraqi invasion of Kuwait last year, but that conflict seems distant. I am here to immerse us in the greatest excitement paleontology has to offer: collecting fossils, being the first to see and figure out each one I pick up. We check in at a hotel in the town of Attock, and fieldwork starts on January 1. We travel to remote sites that I chose from decades-old reports from other paleontologists. The rocks here in the shadows of the Himalayas have their own distinctive charms. They are gnarled, bent, twisted, and overturned, all the result of the mountain-building to the north. They are silent witnesses to the incredibly violent forces that raised the Himalayas to be the world’s highest mountains. With a sense of poetry, my Pakistani colleague, Mr. Arif, calls the limestone that has been tossed into tight bends “the dancing limestone.” A Wasted Digâ |â 3 We search the dry scrublands every day, but fossils are rare; things take time. In my fieldbook I have logged fifty-one fossils. None seem exciting—small pieces of fishbone, crocodile armor, fish teeth, and a piece of the casing of the ear of a whale, the tympanic bone. It is not the first whale bone I ever found. Growing up, in Holland, I lived close to a fossil locality where my father used to take me. A river had dropped rocks there that it collected as it cut through mountains upstream, in Belgium, France, and beyond. There was everything from sea lilies hun- dreds of millions of years old, to plant fossils from coal swamps, and large fossil whale bones from when that area was covered by ocean, just a few million years ago. It cemented my interest in fossils, and for my twelfth birthday I got a rock hammer, which is still the hammer I use now. I have never studied whales before, and now too, whale bones are no good for me. The money from the National Geographic Society is for studying how land mammals migrated between Indo-Pakistan and Asia across the Tethys Sea some fifty million years ago. Whales are of no use for studying migrations on land. I need land-dwelling mammals, and many more fossils, if this grant is to be successful. I am very aware that failing to deliver on a first grant can sink a career. On day five the dream collapses. The United States is threatening to invade Kuwait, and the U.S. government is worried about the safety of its citizens. Mr. Arif is told by his superiors at the Geological Survey of Pakistan to escort us back to Islamabad, the capital. All my plans are crumbling before my eyes. The reason for going back to Islamabad seems ridiculous—the conflict is in the Gulf, not Pakistan. The physical dangers seem much smaller than when I first visited. Why should poli- tics end the field season? Reluctantly, Andres and I return to Islamabad and check into a hotel. The hotel is in the Blue Area, Islamabad’s broad central avenue with shopping areas, as well as the buildings of the president, prime minister, and congress.
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