[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

New York Times on Paul Sereno (lengthy)

In case anyone on the list can't access the New York Times online
Science section, here is a copy of their article on Paul Sereno. I
don't know what the copyright situation is with respect to relaying
such material electronically, but I suspect the Times would take a dim
view of it. On the other hand, since that issue is no longer on the
newsstands, there is practically no other way to obtain the article,
so I don't think we should deprive ourselves of this timeless prose,


June 4, 1996

Accident-Prone Imp Evolved Into Extraordinary Fossil Hunter


   CHICAGO -- It is 9 a.m. on a weekday, and Susan Lesher's
fifth-grade class from the University of Chicago Laboratory School is
agitatedly awaiting the entrance of the dinosaur hunter Dr. Paul
C. Sereno. Minutes later, the door to the lecture room at the
university swings open and Sereno -- in jeans, a West African charm
necklace and one turquoise earring -- strides to the front, grinning
broadly at his adulatory audience. Jaws fall open, revealing braces on
teeth, and a few hands shoot up with burning questions, prompting a
raised-eyebrow caution from Ms. Lesher.

   "Griffin, please wait, please wait," she whispers gently from
halfway across the room.

   The man needs no introduction to these dinosaur disciples. Just
last month, he and his team at the University of Chicago announced
their discovery of fossil remains of two large predatory dinosaurs
that must have been the terror of the flood plain they inhabited 90
million years ago: Carcharodontosaurus saharicus, which means
"shark-toothed reptile from the Sahara," a bipedal dinosaur bigger
than Tyrannosaurus rex, and Deltadromeus agilis, for "agile delta
runner," a relatively lithe, fleet creature.  Carcharodontosaurus was
identified earlier in this century, but Deltadromeus is a new species.

   The pupils have seen Sereno's rugged image on the morning news,
pored over his make-or-break expeditions to Niger and Morocco, and
prepared for this visit to his laboratory by studying a curriculum he
wrote with Gabrielle Lyon, a University of Chicago graduate who
participated in both expeditions.  For the next 90 minutes, Sereno and
Ms. Lyon, who spotted the glint of the crystallized Deltadromeus
marrow under the glaring Moroccan sun, regale the pupils with facts
and stories about their work and the lives of dinosaurs.

   In recent years, Sereno's time has been increasingly in demand, but
visits by schoolchildren frequently dot his agenda. "This could be the
experience that changes a kid's life," he said after the
session. Sereno's account of his own uneven childhood in nearby
Naperville, Ill., suggests a reason for his belief in turning points.

   He was considered a poor student. "I wasn't reading in second
grade," he said. "I couldn't tell time in third grade, and I nearly
flunked sixth grade."

   He was also incorrigibly mischievous and accident-prone. He tried
derailing trains and pelting school windows with rocks, and he landed
in several body-mutilating accidents involving knives and
bikes. Twice, he was rendered unconscious in gym-class mishaps.

   It was yet another misdemeanor that finally set him on a more
virtuous course. "Just a minute. I still have it," he said, rushing
from the room and returning a moment later with the 1956 edition of
"The Fossil Book," wrapped in yellowed cellophane and stamped on all
sides with the words Naperville Community High School Library.

   Yes, he stole it. "There were two copies," said Sereno, who at 38,
views the prank a bit sheepishly. It is a book packed with photographs
of fossils, slimy creatures and colorful stones, and the illustrations
captivated him at a time when he was discovering his own talent in
painting. With the unwavering support of his parents (whose five other
children now also have Ph.D.'s), he enrolled at Northern Illinois
University in De Kalb, majoring in biology and studio art. Then, on a
trip to the American Museum of Natural History in New York, Sereno
became fascinated with the stories of paleontological expeditions.

   "I could combine art, travel, science, adventure, biology,
paleontology and geology," he remembered thinking. "Right then, I knew
exactly what I wanted to be."

   From there, Sereno went on to earn a Ph.D. in geology at Columbia
University in New York. He got a job at Chicago, where he has taught
since 1987 in the department of organismal biology and anatomy.

   In the last decade, he has led and participated in expeditions to
South America, China and, most recently, Africa, where his team made
the first relatively complete discovery of dinosaur remains from the
Late Cretaceous period, the final stage of dinosaur evolution. But in
a field where, according to one paleontologist's estimate, a new
dinosaur species is discovered on the average of every seven weeks, it
is not only Sereno's discoveries that impress some of his colleagues.

   "Sereno's accomplishments aren't what he gets credit for in the
popular media," said Dr. David E. Fastovsky, a paleontologist at the
University of Rhode Island in Kingston and the co-author with
Dr. David B. Weishampel of "The Evolution and Extinction of the
Dinosaurs" (Cambridge University Press, 1996). "He has a truly
well-developed, high-quality eye and breadth of knowledge of the
character of dinosaurs. He knows which dinosaur is related to which as
well as anybody out there."

   Sereno's main interest is in explaining the genealogy of dinosaurs
using cladistic analysis, a relatively new tool that presents dinosaur
relationships as a hierarchy of shared characteristics. In a
cladogram, each branching point, or node, marks a hypothesized
evolutionary step between organisms.

   For example, the earliest branching point in dinosaur evolution was
between the Ornithischia, whose defining characteristics include a
backward-rotated pelvis, and Saurischia, whose defining
characteristics include an asymmetrical hand. By contrast, the old
family trees postulated relationships between organisms without
presenting rigorous anatomical evidence for such connections, Sereno

   In Sereno's African expeditions, he sought to learn how dinosaurs
had evolved once the supercontinent known as Pangea began to break in
two around 150 million years ago. One land mass, which would later
separate into the African and South American continents, moved
south. Another land mass moved north. If the break had been final and
clean, as had been hypothesized, then one would expect to see a clear
branching point between northern and southern dinosaur lines as well.

   But the new Moroccan finds appear to tell a different story. Both
the Carcharodontosaurus skull and the Deltadromeus skeleton were
discovered in sediments that date from tens of millions of years after
the start of the continental split. But both of these dinosaurs, from
the southern land mass, are most closely related to dinosaurs on the
northern land mass. Sereno said that might mean there was a land
connection between the two continents for much longer than has been

   Sereno came upon the first softball-size fragment of the
Carcharodontosaurus skull while surveying the side of a 500-foot-high
incline. When he saw it, he froze in his tracks to avoid crushing any
other bits that might have been underfoot. Then he carefully picked up
the fragment.

   He immediately saw a distinctive triangular depression that is a
distinguishing characteristic of theropods, a group of meat-eating
dinosaurs like Tyrannosaurus rex.

   "My eyes just about popped out of my head," he said. "You pick up
so many pieces like this that are so weathered. You're usually a
million years too late."

   But in this case, Sereno could see that the break was fresh. He
guessed that the skull fragment had fallen off recently -- maybe in
the last 20 years -- from somewhere higher up the cliff. After several
minutes of searching, he recognized the palm-sized matching end of the
piece protruding from a spot 20 feet up.

   Over the next five days, all nine students and paleontologists
worked at the site, painstakingly clearing away the soft rock around
the animal's braincase and snout. Since much of the fossil headed
straight into the cliff, the project was akin to removing one brick
from a wall without having the part above collapse.

   "You have to make a lot of Michelangelo-like decisions about what
the rock can take," Sereno said.

   His solution was to get rid of the cliff above the fossil. "We
moved tons of rock from the side of the cliff to get it out," Sereno
said. As the team members worked, he said, one graduate student was
assigned to cover the exposed fossil with his body.

   "He was like this down there," Sereno said, flexing his knees
slightly, looking up, squinting and holding up his bent arms above his
head. "When a boulder came, he just knocked it away."

   He was only half joking. The physical demands on the eight men and
one woman on the team were extreme. They were in the Sahara desert in
the middle of summer. Some team members lost 20 pounds in 60 days in
the field.

   Backbreaking labor was interspersed with exacting brush and pick
work. The condition of the Carcharodontosaurus bone was like that of a
shattered porcelain plate. To remove the fossil in one piece, the team
hardened it with a glue-like substance as they unearthed it, then
wrapped it tightly in paper, plaster and burlap. Once removed, the
braincase and snout weighed more than 300 pounds, much more than when
the animal was alive because minerals in fossilized bone are heavier
than the bone they have replaced and the cavities inside are packed
with other deposits. In the broken rock below the find, the team
members worked doggedly to recover 400 smaller pieces of the skull.

   "We would not have a skull if we had not sifted the side of that
cliff," Sereno said.

   Perhaps because of his background in art, Sereno is keenly involved
in the visual presentation of his work. He works closely with his
laboratory's illustrator, Carol Abraczinskas, and shot his own video
of the Niger expedition. He and his students helped make the cast of
the Carcharodontosaurus skull that is already on display at the
university's John Crerar Library. On a brief visit there, he fretted
momentarily over whether the lighting was good enough to show the
unusual grooves in the monster's five-inch-long teeth.

   Back in Sereno's lab, work on the Morocco material has been
continuing day and sometimes night, as he, graduate students and
visiting scholars sort through three tons of material from the
expedition, including several canvas bags of sediment.

   "If we pull out five or six mammal crowns out of several hundred
pounds of that sediment, it would be hot stuff," Sereno said, noting
that 90 million years ago, mammals had been no larger than mice.

   Once everything is catalogued and studied, it will eventually
return to Rabat in Morocco, where some fossils will be displayed at
the Museum of the Geological Survey. To look for fossils in the
country, Sereno had to get permission from the Moroccan government,
which is losing a battle against unauthorized dinosaur fossil hunters
who smuggle the precious remains out of the country and sell them on
the antiquities market. In the region in which Sereno and his team
were working, they came upon hundreds of holes showing where fossils
had been extracted.

   That these treasures are disappearing into the cabinets of
collectors at a rate far greater than it takes for the erosion process
to expose the fossils frustrates and saddens Sereno, he said, and
partly explains his rush to visit such sites around the world. He will
do some scouting this summer, and the team will head to northern
Patagonia in Argentina next November.

   "We're going to be exploring and publishing as fast as we can for a
number of years," he said.

Copyright 1996 The New York Times