Paleontology in California
The Bureau of Land Management (BLM) in California manages a diverse assortment of fossils and fossil-bearing formations, representing tens of millions of years of Earth's history. In the South Coast Range, moreno shale derived from fine-grained sediments deposited 65 million years ago in a warm, shallow marine environment containtains the highest diversity of organisms from the late Cretaceous period in the western United States. The Barstow Formation of the Mud Hills in the Mojave Desert is world renowned for fossils of ancient mammals that define the Barstovian Land Mammal Age (12.5 to 16 million years ago). During this time the area was an Africa-like savannah with wetlands where carnivorous saber-toothed cats, mountain lions, and giant bear dogs preyed upon camels, horses, and mastodons. Several world class paleontological localities such as the Maricopa and McKittrick brea pits, Shark Tooth Hill, Bena Road petrified forest, Chico Martinez Creek and the Bopesta Formation-Horse Canyon fossil beds attract scientists to BLM-administered lands in the Bakersfield region.
Saber Cats, Lions and Bear Dogs: In the Mojave Desert, the Barstow Formation of the Mud Hills north of Barstow holds fossils of ancient mammals that define the Barstovian Land Mammal Age. This period of time, 12.5 to 16 million years ago, is recognized across the North American continent. Carnivorous saber-toothed cats, mountain lions, and giant bear dogs preyed upon camels, horses, and mastodons. Bone-crushing dogs cleaned up the left-overs. Rodents, including deer mice, kangaroo rats, and gophers, scurried or hopped to safety, while beavers hid in ponds. Overhead, eagles and flocks of flamingos watched the activity below. During that time, this area was an African-like savannah with wetlands and slow-flowing streams that connected to the distant Pacific Ocean. The hot Miocene climate was cooling by 14 million years ago. Walnut, oak, spruce, cypress, and pine covered distant hills. Horsetails, palm, willow and hackberry lined the streams. Climate change may have caused floral and faunal replacement and widespread increase in grassland.
Current research by the University of Michigan, Bob Reynolds, CSU Desert Symposium, and the Raymond M. Alf Museum of Paleontology involving BLM-administered land is presented in the 2015 CSU Desert Symposium (enter "annual desert symposium" in search box for list of publications).