David Fastovsky, Professor
Department of Geosciences
David Fastovsky earned a BA in biology from Reed College, an
MA in paleontology from the University of California, Berkeley,
and a PhD in sedimentary geology from the University of Wisconsin,
Madison. He has been at URI since 1986. During the past 15 years
he has reconstructed ancient environments in Arizona, Montana, North
Dakota, Mexico, and Mongolia, where dinosaurs lived.
This is a story about the ancient
environments of Protoceratops, the diminutive, plant-eating
dinosaur that first thrilled the world 80 years ago when Roy Chapman
Andrews cabled reports of its existence to the United States (see
Fig. 1). Andrews' teams had found the remains of the beast and
its eggs, demonstrating for the first time that dinosaurs laid
eggs. The discovery was made at the remote Flaming Cliffs area
in the Gobi Desert in southeastern Mongolia. As remote as Mongolia
was from the United States of the 1920s, however, the 70-million-year-old
world Andrews unearthed was infinitely farther removed.
As it turned out, that world was
perhaps too far removed from Andrews, because much of what he
concluded has since become suspect. In 1995, researchers from
the American Museum of Natural History showed that Andrews' Protoceratops
eggs actually belong to Oviraptor. Oviraptor, a
creature whose name (literally "egg thief") belies its
motherhood, was actually guarding its own nest. With the eggs
shown to belong to another dinosaur, what did we really know about
Protoceratops? Since 1993, I have traveled regularly with
Japanese Mongolian Expeditions to the Gobi Desert to find some
The Gobi is still remote. Planes
fly into Beijing, Seoul, and Osaka, but then the isolation sets
in: To reach our research sites, we have to fly to Ulan Baator
and then ride in converted Russian troop carriers for three days
on bumpy dirt trails (or no trails) to the heart of the Gobi Desert
(see Fig. 2).
With temperatures exceeding 110o
F, the Gobi is as inhospitable as it was in Chingis (or Genghis)
Khan's day. It consists primarily of plateaus paved with chert
pebbles that glisten from incessant polishing by dust-laden winds.
A few scrubby shrubs struggle to survive. Peeking out from beneath
the plateaus are soft and treacherous sandy exposures, the remnants
of the 70 million-year-old dinosaur-bearing landscapes.
Our expeditions haul gas and water
with lumbering, overloaded Russian trucks that commonly founder
in the pliant sands and must be dragged free (see Fig. 3). Cables
are attached, go taut, wheels spin, and cables snap: it is always
a rather uncertain process at best. We carry some food, but much
we buy on the hoof (literally) from nomadic herdsmen who raise
sheep and goats for meat and keep camels and horses for transportation,
milk, cheese, and an alcoholic yogurt called airag.
We cannot carry all the water needed
for six weeks. Instead we hunt for wells using old Russian maps
and the advice of local herdspeople. The wells were built in the
1960s and consist of large, low cement pyramids, each with a long
handle and a trough. Most no longer function, and the housings
and troughs have weathered into large, useless cement slabs. Some
functioning wells yield surprises: at one well, after fighting
biting flies and hauling about 80 gallons of water, bucket by
bucket, the last bucket brought up a dead bird.
The modern-day Gobi takes its toll
on all who live there. For those of us unaccustomed to these conditions,
it can be brutal. What was it like 70 million years ago when the
dry sands that trapped our expedition were part of the living
The answer was found, along with
specimens of Protoceratops, at Tugrikin-shireh in the south
central Gobi Desert. Tugrik, as it is commonly known, is the richest
fossil locality that I have ever seen. The skulls and postcranial
bones of Protoceratops are everywhere and five or six complete
skeletons were found along a horizon that we dubbed "Protoceratops
Row" (see Fig. 4). Why was Protoceratops so abundant
at Tugrik? Did it live there, or were its remains somehow concentrated
into an extremely rich deposit?
The evidence that Protoceratops
lived at Tugrik came from the 1994 discovery of two nests full
of babies. The nests are small, bowl-shaped depressions that contain
as many as 15 babies, each about 6 inches long (see Fig. 5). In
both nests, the babies' heads are oriented in the same direction,
facing away from the ancient prevailing winds. Protoceratops
must have lived at Tugrik if it built nests there.
What was Tugrik like 70 million
years ago? The answer is in the sands. We recognized large dipping
surfaces, hundreds of meters long, which could be unambiguously
reconstructed as the lee faces of gigantic ancient sand dunes
(see Fig. 6). These ancient dunes were the kind that occur in
modern dune-rich deserts, such as the Sahara. The ancient Tugrik
dunes were large; as high as 80 feet and, given their size and
distribution, they must have been extensive. Windblown sand dune
fields---sand seas---are today called ergs. The ubiquitous sand
that surrounded us was ubiquitous 70 million years ago: Protoceratops
lived in the midst of an erg.
What was a nice dinosaur like Protoceratops
doing in a place like this? The skull bones and teeth indicate
Protoceratops was well-suited to cropping and shearing
plants. And yet this was not the kind of environment in which
one might expect much vegetation. Again, Tugrik surprised us.
Some of the ancient lee sides of the dunes preserve forests of
beautifully lithified plant roots intertwined with insect burrows
(see Fig. 7). This suggested that despite the desert environment,
Tugrik was rich and productive. We can speculate that the ancient
denizens of Tugrik were adept at obtaining moisture, perhaps from
early morning dew. Tugrik must have been a thriving ecosystem,
as the fossils reflect an abundance of life.
Why it ended remains a mystery.
At Tugrik, it appears that life was snuffed out by the relentless
migrating sand dunes. Most likely, they stilled the nests of embryos
and caused the deaths along Protoceratops Row. Protoceratops
and its cohorts may have mastered living in a sand sea, but one
suspects that this extreme environment, like its modern counterpart,
allowed few missteps.