Irvington Fossil Locality
This is the type area for the Irvingtonian Mammalian age, the best early Middle Pleistocene fauna in the West.
Among the mammals whose fossils have been recovered here are a number of genera still found in the Bay Area such as
Citellus (ground squirrels), Thomomys (pocket gophers), Perognathus
(deer mouse), Neotoma (packrat), Microtus (vole), Odocoileus (deer), and a coyote,
Additionally there are a number of other species which are either extinct or whose descendants are found in other parts of the world. These include a ground sloth,
Megalonyx, dire wolf, Canis dirus, sabre-tooth cat, Dinobastis, mammoth,
Mammuthus columbi, horse, Equus, several peccaries of the family
Tayassuidae, two species of camels, Camelops minidokae and
Tanupolama sp., an antilocaprid with four horns, Tetrameryx
irvingtonensis, and a musk-ox like animal, Euceratherium.
Integrity: Interstate 680 passes over the known fossil site; however, the fossils have been studied over a number of years and removed before construction. Road cuts have revealed additional sediments similar to the fossil-bearing sediments.
Use: Research only
Ref: Savage, D. B., 1952. Cenozoic Vertebrates of the San Francisco Bay Region. University of
California Dept. Geol. Sci. Bull. 28, No. 8.
Inventory of California Natural Areas
Revision © 2005 Steven Louis Hartman