John M. Harris, Ph.D. Chief Curator and Department Chair; RANCHO LA BREA DEPARTMENT
(George C. Page Museum)
STAFF
John M. Harris, Ph.D. Chief Curator and Department Chair;
Head, Vertebrate Studies Division
Interested in Pleistocene mammals of North America
and Neogene ungulates from Africa.
(323) 857 6300 xt 131
Christopher A. Shaw, M.S. Collections Manager
Interested in Plio-Pleistocene mammals of North America
and functional morphology of saber-toothed carnivorans.
(323) 857-6300 xt 124
Shelley M. Cox, B. A. Laboratory Supervisor
Interested in fossil bears
(323) 857-6300 xt 120
Cathy McNassor, M.A. Archivist
Interested in history of paleontology in the American West
and Chester Stock
(323) 857-6300 xt 130
Kristen Brown, B.S. Senior Excavator
Interested in Pleistocene mammals
(323) 657-6300 xt 122
Andrea Thomer, B.A. Excavator
Interested in megafauna and extinction events
(323) 857-6300 xt 122
email: athomer@tarpits.org
COLLECTION
The Rancho La Brea collections are housed on site at the George C. Page Museum in
Hancock Park. The collections document the Rancho La Brea biota and include some 3.5
million specimens representing over 600 species of animals and plants. The site-specific
collections also include geological samples, archeological artifacts, historical objects, a
library, an archive, and collections of correspondence and ephemera related to the
locality. Vertebrate fossils from other asphaltic fossiliferous localities in California are
housed in the collections of the Vertebrate Paleontology Department of the Natural History
Asphalt seeps in the southwest corner of the Mexican land grant of Rancho La Brea have
been exploited since prehistoric times. Native Americans used the sticky asphalt as a glue
and a caulk and early settlers in Los Angeles used it as for roofing material, fuel and a
preservative. The first record of fossils from the asphalt seeps was published in 1875 but
collecting did not begin in earnest until the early twentieth century. The 23 acres that
constitute the most richly fossiliferous area was donated to the County of Los Angeles in
1924 by landowner Captain G. Alan Hancock. The locality became California State
Historic Landmark No. 170 in 1940 and a National Natural Landmark in 1963. The La
Brea tar pits became the type locality of the Rancholabrean Land Mammal Age in 1951.
The Rancho La Brea biota is one of the world’s richest and most diverse late Pleistocene
terrestrial assemblages. It is perhaps best known for its extensive holdings of carnivorans
of which dire wolves (Canis dirus, 4,000+ individuals), saber-toothed cats (Smilodon fatalis,
2,000+ individuals) and coyotes (Canis latrans) predominate among the 60+ species of
mammals. Asphalt is a superb preservative for delicate bones and the collection of fossil
birds from Rancho La Brea is one of the world's largest. Collections made in the early
twentieth century concentrated on the larger fossil specimens but the current Pit 91
excavation was initiated in 1969 to collect all the fossil material including microfossils.
Nearly all of the plants (160 species), insects (149 species), mollusks (56 species), fish
(3 species), amphibians (5 species) and reptiles (24 species) are known only from Pit 91.
NEW RESEARCH
Scientists from the University of California, Riverside, have discovered more than two hundred
species of bacteria and archaea living in the asphalt seeps in Hancock Park.
USEFUL REFERENCES
Denton, W. 1875. On the asphalt bed near Los Angeles, California. Proceedings of the
Boston Society of Natural History, 18:185–186. [First description of fossils from Rancho
La Brea]
Harris, J. M. (Ed) 2001. Rancho La Brea: death trap and treasure trove. Terra, 38, no.2:
1-56. ["Popular" account]
Savage, D.E. 1951. Late Cenozoic vertebrates of the San Francisco Bay region.
University of California Publications in Geological Sciences, 28 (10): 215–314.
[Publication that established the Rancholabrean Land Mammal Age]
Shaw, C.A., and J.P. Quinn. 1986. Rancho La Brea: A look at coastal southern
California's past. California Geology, 39 (6):123–133. [Geological summary]
Stock, C. and J. M. Harris. 1992. Rancho La Brea: A record of Pleistocene Life in
California. (7th edition). Natural History Museum of Los Angeles County, Science Series,
No. 37; 113pp. [Standard reference with faunal list and extensive bibliography]
RECENT PUBLICATIONS
Spencer, L. M., B. van Valkenberg, and J. M. Harris. 2003. A taphonomic investigation
of Pit 91, Rancho La Brea. Paleobiology, 29 (4): 561-575.
Coltrain, J. B., J. M. Harris, T. E. Cerling, J. R. Ehleringer, M. Dearing, J. Ward, and J.
Allen. 2004. Trophic level relationships among Rancho La Brea fauna and their
implications for the paleoecology of the late Pleistocene based on bone collagen stable
carbon and nitrogen isotope chemistry. Palaeogeography, Palaeoclimatology,
Palaeoecology, 205: 199-219.
Ward, J. K., J. M. Harris, T. E. Cerling, A. Weidenhoeft, M. J. Lott, M. Dearing, J. B.
Coltrain, and J. R. Ehleringer. 2005. Carbon starvation in glacial trees recovered from the
La Brea tar pits, southern California. Proceedings of the National Academy of Sciences,
102: 690-694.
Christiansen, P. and J. M. Harris. 2005, The body size of Smilodon (Mammalia: Felidae).
Journal of Morphology, 266: 369-384.