Joshua B. Smith, Ph.D.
Assistant Professor of
Earth & Planetary Sciences (starting August 2002)
Washington University,
St. Louis
Josh Smith studies the
interactions between ancient organisms and their environments, particularly
the paleoecology of ancient ecosystems that contained dinosaurs. He can trace
his interest in geology and paleontology to the age of six, when he received
his first dinosaur book as a gift. Today Smith’s efforts are largely
focused on a sequence of 94 million-year-old rocks in the Bahariya Oasis of
Egypt that has produced one of the most enigmatic dinosaur faunas ever discovered,
including some of the largest known terrestrial animals. He has been directing
this project since its inception in 1999. Smith earned a B.S. in geology from
the University of Massachusetts at Amherst in 1994, as well as an Sc.M. in
geology (1997) and a Ph.D. in paleontology (2002), both from the University
of Pennsylvania. He was a National Association of Geology Teachers Fellow
in 1994 and a Paul Bond Scholar in 1996. He is a member of Emmanuel College,
Cambridge University, an invited member of both the Geological Society of
America and the Society for Sedimentary Geology, and has held positions with
the United States Geological Survey, the Smithsonian Institution, and Harvard
University. Smith is the author or co-author of 14 scientific articles and
has conducted fieldwork in Alberta, Argentina, Connecticut, Egypt, Massachusetts,
Pennsylvania, Wyoming, Puerto Rico, the Canadian High Arctic and China. He
currently lives in St. Louis, where he is Assistant Professor of Earth and
Planetary Sciences at Washington University.
In the early 20th century,
the Bavarian geologist Ernst Stromer directed a series of expeditions that
recovered a diverse fossil biota from the Upper Cretaceous (Cenomanian) Bahariya
Formation of the Bahariya Oasis, Egypt. The vertebrate finds included fish,
turtles, plesiosaurs, squamates, crocodyliforms, and four dinosaurs (the theropods
Carcharodontosaurus, Spinosaurus, and Bahariasaurus and the
sauropod Aegyptosaurus) that are among the most enigmatic known. Bombs
falling on Munich in 1944 destroyed virtually all evidence of this assemblage.
The loss was particularly acute because a solid understanding of the terrestrial
biota of Late Cretaceous Africa is important for the paleoecology of this
region and for the evaluation of biogeographic hypotheses pertaining to Gondwanan
fragmentation.
In early 1999, a reconnaissance
team from the University of Pennsylvania conducted the first successful search
for fossil land animals in Bahariya since the World War II loss of the Bavarian
collection. This and several subsequent expeditions have yielded some six
tons of fossil bony and cartilaginous fishes, turtles, squamates, dinosaurs,
bivalves, gastropods, leaves, and fruits. Preliminary results indicate that
the Bahariya Formation consists of a suite of paralic and near-shore marine
lithosomes that were laid down along an epeiric bight, which extended south
from the Tethys Seaway during high sea level stands of the Cenomanian. So
far, all of the biotic remains discovered have been preserved in low-energy
paralic sediments that appear to represent vegetated tidal flats and tidal
channels. Clast sizes, sedimentary structures, plant remains, and stratigraphic
relationships are all indicative of a mangrove coastline interpretation of
the Bahariya paleoenvironment.
That the ancient Bahariya
ecosystem was occupied by a very diverse biota which contained both some of
the largest herbivores known and three Tyrannosaurus-sized predators
(Bahariasaurus, Carcharodontosaurus, and Spinosaurus) suggests
a paleoenvironment of very high biological productivity. Of particular note
among the discoveries so far are woody bases of the mangrove tree fern Weichselia
reticulata in growth position, the rediscovery of several taxa lost to
science since the Munich bombing (including the 3 + meter-long coelacanth
Mawsonia libyca) and several new taxa, including the first Cretaceous
occurrence of majoid crabs, a new species of dromaeosaurid theropod, and the
herbivorous dinosaur Paralititan stromeri, which is in contention for
the most massive terrestrial animal yet described.
Read about this discovery
in Science Magazine!
Watch The Lost Dinosaurs
of Egypt on A&E Oct. 8 and 12, 2002 from 9:00 – 11:00 pm.
ost
Dinosaurs of Egypt: Adventures in North African Paleontology