The Walking Whales

by J G M Hans Thewissen

needs of the fossil collector into account. As a result, most of Sunil’s

  localities are near bus lines. He would often arrive at a site before the

  sun was up, wait for it to get light, and then leave when the bus came by

  on its return journey in the early afternoon. It gave him little time to

  collect, and he was limited in the amount of tools he could bring and the

  number of fossils he could collect. The collection he put together is sur-

  prisingly large.

  We now have a small grant from the National Geographic Society

  and are able to rent a car. In India, one cannot rent just a car, one always

  86    |    Chapter 6

  rents it with driver. Naveem is a quiet and gentle man and, importantly

  to me, a careful driver. The car is an Ambassador, built in India, without

  four-wheel drive. Naveem takes pride in driving it off the paved road

  through streams and hogbacks. Only once do these get the better of him

  and we end up suspended on the bumpers while trying to cross a ditch.

  With a reluctant smile, he tells us that he will not use that track again.

  Naveem drops us at Babia Hill, a flat-topped hill with intense weath-

  ering on its slopes. The nalas (dry streambeds) are all bone-dry early in

  the year; they only carry water in the monsoon season in the fall. Sunil

  finds some ribs weathering out of the wall of such a nala. They are lined

  up in a row and are as thick as broomsticks. A large thorn bush casts its

  irregular shadow over them. The fat ribs immediately identify the fossil

  as sirenian, and I notice that another row of ribs is on the other side of

  the  thorn  bush,  also  nicely  lined  up.  This  was  a  chest,  buried  in  its

  entirety. I can’t wait to see the vertebrae between the ribs, underneath

  the thorn bush. I hack at the bush with my knife, and the excavation

  starts. The vertebrae show that the head side of the beast pointed into

  the nala, so the skull was probably washed downstream during some

  monsoon flooding. It could have been last year, or a thousand years ago.

  On the off chance that it was recently, I leave my backpack with the

  sirenian chest and walk down the nala. A short walk down, a piece of

  bone sticks out of the bank. I dig into the bank with the back of my

  hammer. It is a jaw—I see the cavities for teeth, and, deeper, a tooth!

  However, it is not a sirenian tooth but a beautiful whale tooth. I expose

  a second tooth with my pocket knife. It is slow going, because the more

  appropriate tools are in my backpack. The jaw goes deeper still, into the

  wall. To get this out I should get my preparation tools—but I should

  really first finish the sirenian chest, and my quest for its head. As I strug-

  gle with priorities, Sunil comes and tells me that he has found something

  else. I leave my hammer with the jaw as a marker, so I can easily find its

  spot in the twisting nala, and follow Sunil. Another short walk, and he

  points at a white object protruding from a crack in the nala’s side. The

  only tool I have now is my pocket knife. I try to cut away at the red

  brown mud. The fossil is bright white, a color that indicates gypsum

  here. Gypsum is a mineral that is dissolved in the water, and when it is

  abundant,  it  often  replaces,  molecule  by  molecule,  fossil  bones  and

  teeth. Environments where this happens are often enclosed bays that are

  filled with seawater and that dry up. As the water evaporates, the gyp-

  sum concentration goes up, and eventually the gypsum forms crystals

  that  replace  the  bones  and  teeth  of  an  animal.  Some  gypsified  fossils

  Passage to India | 87

  keep the shape of the original fossil quite well, but some deform it

  beyond recognition, and gypsum is hated by many paleontologists. I use

  my pocket knife to cut away the sediment around the fossil, and what is

  revealed looks good. It is a very narrow bone, with two rows of small

  circular holes lined up along its length, like the holes in a flute. Another

  whale jaw—the holes are the sockets for teeth!

  Overwhelmed, I sit down on the dirt, resting my head in my hands,

  not knowing how to proceed. My tools and backpack are at one excava-

  tion, my hammer at another, and me and my knife at a third. Getting the

  two jaws out will take about an hour each, and the chest will take half a

  day. Too many fossils is a nice problem to have, but it remains a problem.

  Eventually, I remove the fossils in the opposite order in which they

  were found. Neither fossil is similar to the whales I know so well from

  Pakistan. The flute look-alike belongs to a relative of the skull in Sahni’s

  lab, a remingtonocetid (to be discussed in chapter 8), and the other jaw

  is from a protocetid whale (to be discussed in chapter 12).

  If Ambulocetus bridges the gap between land mammals and whales,

  these Indian fossils could bridge the gap between the Pakistani fossils

  and basilosaurids. If whale origins were a puzzle, we previously just had

  some intriguing pieces, but could not make out the image on the puzzle.

  With the addition of the Indian fossils, we can find enough pieces so

  that the image may become clear—as long as we have the time and

  money to collect them.

  a 150-pound skull

  We are back in Kutch a year later, searching old and new localities. At

  Rato Nala, the road climbs a shallow escarpment that includes the out-

  crops of the Harudi Formation, a belt of rocks, three hundred yards

  wide, perpendicular to the road. It was a stretch of coast forty-two mil-

  lion years ago. Drab comes in many shades here: greenish, brownish,

  yellowish, mostly coloring muds. If you look closely, you see some

  brighter veins: thin layers of bright-yellow sulfurous rocks, glassy white

  gypsum layers, and nearly black seams of coal, never more than finger

  thick. The coal indicates abundant plant growth, marshes at the water’s

  edge. To the eye, the most dominant type of rock is the Chocolate Lime-

  stone, a brown layer of limestone chock-full of bright-white snails and

  clams that indicate that this was ocean floor.

  Looking north, beyond the Harudi, the place looks like a barren

  moonscape: miles of brick-red, blood-red, and black sandstones and

  88    |    Chapter 6

  Shale with fossil

  foraminifera

  Shale with plant fossils

  Occasional

  Chocolate Lim
estone with

  fossil mammals

  Blue-gray shale

  lots of fossil whales

  Gray and green shales

  Gray and green shales

  Gray slits

  figure 28. A geological section of the Eocene rocks of Kutch in western India.

  mudstones, eroded into irregular shapes that make it hard to walk on

  (figure 28). This is the Naredi Formation, which was formed in a period

  of intense Eocene weathering. Rains leached the soil, leaving only the

  least soluble minerals behind. The dark colors are mostly iron oxides,

  rust basically. With all the nutrients gone, modern plants, too, find it

  difficult to live there. The Naredi was formed before the Harudi Forma-

  tion.  Looking  south,  the  Harudi  ends  at  the  top  of  the  escarpment.

  There,  the  Fulra  Formation  appears  as  a  raised  plateau  consisting  of

  blocks of hard and bright-yellow limestone with lots of clams and sea

  urchins, and snails the size of footballs, but no vertebrates. The Naredi

  rocks  were  formed  when  the  land  was  exposed  by  weathering. After

  that, the ocean level rose, and the Harudi formed at a time when the

  coastline was here: muddy beaches, oyster banks, coastal swamps, and

  islands. The ocean kept rising and flooded more land, and there was a

  shallow, warm, and very productive sea, as documented by the reefs of

  the  Fulra  Formation.  Geologists  read  the  rocks  as  if  they  are  the

  book that describes the history of a place. In Kutch, the book describes

  how,  as  the  ocean  flooded  the  land,  a  continental  edge  was  slowly

  drowned.

  The Chocolate Limestone forms the top of a row of low plateaus,

  flat-topped hills that can be up to sixty feet in height and half a mile in

  length. This is a good place to find whale fossils. We spend much of our

  time walking along the edges of the plateaus, where fossils become vis-

  ible as they erode. A piece of bone on the slope triggers an intense on-

  your-knees investigation, head to the ground, scouring the surface. Even

  though this area is rich, a good day means having three fossils in your

  backpack upon return. Rich in fossils is a relative concept.

  Passage to India | 89

  I like this place, partly because it is so remote. If you walk away from

  the road, you cannot see anything human-made, even though you can

  see for miles. The quiet is also beautiful. In the heat of the day, you can

  listen intently and hear absolutely nothing for minutes, when the quiet

  is just subtly disrupted by the faint hum of a distant insect flying by or

  a rare whisper of wind. The atmosphere makes me imagine looking

  back in time, when whales swam here.

  Suddenly, Sunil wakes me from my musings as he calls from afar. He

  is running toward me, reaching me, exhausted, red-faced, catching

  his breath.

  “Hans, Hans, I found a skull, the best skull I ever found.”

  We rush to the place. The specimen is totally embedded in Chocolate

  Limestone. We can see only the top of the skull, a ridge of bone that is

  the crest on top of a skull, the sagittal crest. It is embedded in limestone;

  the bone undulates in a pattern identical on the left and right side of the

  skull, wider where the eyes are, and forward onto the snout for about

  three feet. It feels as if I am standing on a boat on the ocean, and an

  Eocene whale is surfacing immediately next to me, only the top of his

  head emerging from the water. Sunil is right. This will be an amazing

  skull. The part that is popping out of the limestone is perfect. Our ham-

  mers loosen the baked dirt and my whisk broom sweeps it away. The

  limestone under our feet is not a massive layer; instead, it is broken up

  into large blocks. The piece with the whale skull is bigger than the oth-

  ers. It is the color of milk chocolate, with white snails and clams as

  marshmallows. But this is better than chocolate.

  We excavate around it, and after a few hours, it is clear that the block

  is much too heavy to be lifted by one person and carried to the road,

  two miles off. We consider breaking it into pieces for transport. But the

  limestone breaks irregularly, and the incessant hammering causes cracks

  to form in places where they may easily pulverize fossil bone during

  transport. No, it has to come out as one piece. Dr. B. N. Tiwari, the third

  member of our group, solves the transportation problem. He cuts down

  two small trees, and we suspend the block from them with ropes. The

  driver takes our car on a circuitous route, finding flat spots, cross-coun-

  try, toward us. There are just two hundred feet from fossil to car now.

  We suspend the fossil in its hammock. The slope is steep, slippery, and

  rock-littered. Like drunken sailors, the four of us stagger down, our

  load swaying with every step someone takes. Lifting it into the back of

  the car is not easy either, and the car sags perilously under its weight.

  But we make it to town. A local carpenter adapts a salvaged box to hold

  -SB 2517,

  Drawing of

  Anatomy of Middle

  Two Eocene Cetaceans

  , “Cranial

  hicetus,

  .

  utc

  is based on four fossils (IITR

  K

  . Conley

  and

  and R.W

  , seen from three different angles.

  Andrewsiphius

  Andrewsiphius

  Thewissen,

  M.

  . G. J

  S.,

  Andrewsiphius sloani

  y 85 (2011): 703–18).

  and

  Bajpai,

  aleontolog

  “New Skeletal Material of

  from S.

  Both used with permission of the Paleontological Society

  Bajpai,

  -SB 2770,

  ” Journal of P

  Remingtonocetus harudiensis

  Thewissen and S.

  Mammalia),

  y 83 (2009): 635–63).

  M.

  . G.

  (Cetacea,

  aleontolog

  from J

  is based on a single fossil (IITR

  Skull of the fossil whales

  and 3153,

  ” Journal of P

  e 29.

  Remingtonocetus

  r

  2907,

  u

  fig

  Remingtonocetus

  Eocene

  2724,

  from India,

  Passage to India | 91

  the fossil. We stuff empty, tightly closed mineral water bottles around

  the block as shock absorbers. I am pleased with the improvised result as

  I prepare the specimen for shipment to the United States.

  I am not pleased with the bill. Shipping it will cost over a thousandr />
  dollars. I do not have that much, so I leave the specimen with Sunil. The

  fossil finally reaches the United States some years later, and my fossil

  preparator spends a full year to extract the fossil from the block, knock-

  ing tiny pieces of rock off the fossil with a pen-sized jackhammer. The

  result is amazing. This is certainly the most beautiful whale skull that

  Kutch has ever produced (figure 29, skull on left).

  Chapter 7

  A Trip to the Beach

  the outer banks

  Driving to the South Carolina Coast, 2002. I think of the long-extinct

  Indian whales as I drive with my family on a vacation trip to Kiawah

  Island in South Carolina. Weedy forests cover the mainland, like the

  “dense jungle” of the Pakistani maps, and they suddenly give way to flat

  marshes, swamps, and winding river channels at the shore. The bridge

  is long, but as we cross it, I can see the ocean across the island.

  Geologists call islands like Kiawah barrier islands. They are basically

  sandbars that rise above the sea and grow when they are fed with sand

  by the waves and currents. Wind remodels the exposed parts, making

  dunes, and when plants get a chance to grow and anchor the sand, they

  freeze the dunes in place, until a big storm tears them up again. Barrier

  islands are long and narrow, extending along the coast. On the land side

  of these barrier islands is the Intracoastal Waterway, a low area which

  geologists refer to as a backbay. Rivers feeding freshwater into the back-

  bay are blocked from the sea by the barrier islands. This creates a marsh

  between islands and mainland. Eventually, the rivers cut tidal channels

  between islands, spilling their water into the ocean. The ocean fights

  back at high tide, pushing seawater into the breaks between the islands

  and overwhelming the backbay. Then, at low tide, the flow reverses

  again. Freshwater and seawater mix, and the saltiness of the water var-

  ies, from very salty near the tidal channels to hardly at all away from the

  93

  94    |    Chapter 7

  channels. The flow of the rivers decreases greatly as it hits the backbays,

  and with that, it also loses the ability to carry sediment. The rivers car-

  ried mud, and the mud is dumped in the backbays, creating a rich, nur-