Sheep, Goats, and Oxen of Anza-Borrego Desert State Park
Ancient Members of the Cattle Family in Southern California

Sheep, goats, and oxen belong to the family Bovidae, one of the world's most successful groups of hoofed mammals. Although bovids arrived in North America relatively late compared with horses, camels, and pronghorn, they became an important part of Ice Age ecosystems. Fossils preserved in Anza-Borrego Desert State Park document the appearance of these animals during the Pleistocene and provide evidence for changing climates and expanding grasslands in southern California.

The fossil record of Anza-Borrego includes early bison, bighorn sheep, and extinct members of the musk ox lineage, illustrating the arrival and diversification of bovids in western North America.

Bovids in Ancient Anza-Borrego
By the early Pleistocene, the environments of Anza-Borrego had become increasingly open and seasonally dry. Grasslands expanded across parts of the region, supporting a growing diversity of grazing mammals. Among the newest arrivals were members of the cattle family, which joined horses, camels, deer, pronghorn, and mammoths in the Park's evolving ecosystems.
These large herbivores became important prey for Ice Age predators, including saber-toothed cats, dire wolves, and short-faced bears.

Bison
The best-known bovids from Anza-Borrego are the bison, represented by both early and more advanced species.
The earliest forms were smaller than the enormous bison that later spread across the Great Plains. Over time, bison evolved into increasingly successful grazers capable of exploiting the expanding grasslands of North America.

Their appearance in the Anza-Borrego fossil record reflects broader environmental changes toward cooler, drier climates during the Pleistocene.

Bighorn Sheep and Musk Ox Relatives
Fossils of bighorn sheep (Ovis canadensis) demonstrate that rugged mountain habitats similar to those occupied today already existed in portions of southern California during the late Pleistocene.

The fossil record also includes members of the Ovibovini, the tribe containing modern musk oxen. Although these extinct relatives differed from living musk oxen, they represent an important stage in the evolution and dispersal of bovids across North America.
Together, these animals illustrate the remarkable diversity of the cattle family during the Ice Age.

What Bovids Tell Us
Fossils of sheep, goats, and oxen help scientists reconstruct:
  • The expansion of grassland habitats
  • Climate and environmental change during the Pleistocene
  • The evolution of North American grazing mammals
  • Predator-prey relationships
  • The arrival of modern mammal communities in southern California
Because bovids are closely tied to vegetation and climate, their fossils provide valuable evidence for understanding changing ecosystems through time.

Explore a Fossil in 3D
Rotate, zoom, and examine this specimen from the Anza-Borrego Desert State Park collections.
Interactive 3D Model: Bison vertebra
Specimen Information
  • Catalog Number: ABDSP3904 V9260
  • Element: vertebra, cervical
  • Formation: Bow Willow
  • Epoch: Pleistocene
  • Age: Irvingtonian
  • Locality: Carrizo Badlands
  • Scanned using Agisoft Metashape
  • Specimen © California State Parks. 3D model produced by the Anza-Borrego Desert State Park Paleontology Society.
Why Anza-Borrego Matters
Anza-Borrego Desert State Park preserves one of North America's most important late Cenozoic fossil records. Fossil bovids document the relatively recent arrival of the cattle family into southern California and their role in the increasingly modern ecosystems that developed during the Pleistocene.

Together with horses, camels, deer, pronghorn, mammoths, and other large herbivores, sheep, goats, and oxen help reconstruct the rich grazing communities that once inhabited the region long before today's desert landscape emerged.

The Fossil Record
Family Bovidae
  • Bison (Bison)
  • Ancient bison (Bison antiquus)
  • Bighorn sheep (Ovis canadensis)
  • Shrub oxen (Euceratherium)
Quick Facts
Family: Bovidae
Includes: Bison, bighorn sheep, and extinct musk ox relatives
Famous species: Bison antiquus and Ovis canadensis
Age: Pleistocene
Role: Large grazing herbivores
Significance: Evidence for the spread of grasslands and the arrival of modern grazing mammals in southern California
Location: Anza-Borrego Desert State Park, California

Learn More
Read Chapter 16, "Smaller Artiodactyls: Peccaries, Oxen, Deer and Pronghorns," in Fossil Treasures of the Anza-Borrego Desert for a detailed discussion of the bovids that inhabited ancient Anza-Borrego Desert State Park and what they reveal about the changing landscapes of southern California.