Mammoths and Their Relatives of Anza-Borrego Desert State Park

Giants of the Ancient Colorado Desert
Among the most spectacular fossils discovered in Anza-Borrego Desert State Park are the remains of mammoths and their relatives. These enormous members of the Order Proboscidea include mammoths, mastodons, gomphotheres, and the ancestors of modern elephants. Their fossils provide important evidence for the changing environments of southern California during the Pliocene and Pleistocene.

Proboscideans first evolved in Africa more than 30 million years ago. Over time they developed trunks, tusks, and specialized teeth that allowed them to become some of the largest land mammals ever to walk the Earth. Several different proboscidean lineages eventually reached North America, where they diversified and spread across the continent.

Mammoths in Anza-Borrego
The most famous proboscidean discovered in Anza-Borrego is the southern mammoth, Mammuthus meridionalis. In 1986, paleontologist George Miller discovered the remains of an exceptionally complete specimen in the Borrego Badlands. After years of excavation, a massive skull weighing approximately 1,400 pounds and an 11-foot tusk were recovered and transported by helicopter to the Stout Paleontology Laboratory.

The Anza-Borrego specimen is recognized as one of the most complete southern mammoths known from North America. This remarkable discovery brought international attention to the park and demonstrated the scientific importance of its fossil deposits.
Southern mammoths were among the earliest mammoths to enter North America. They were larger and more primitive than the later Columbian mammoths that became widespread during the Ice Age. Their fossils help scientists understand the evolutionary history of mammoths and the environments they inhabited.

There are over 80 mammoth, mastodon and gomphothere sites in Anza-Borrego Desert State Park.

Mastodons and Other Proboscideans
Mammoths were not the only elephant relatives that lived in ancient southern California. Fossils from Anza-Borrego also document the presence of mastodons and gomphotheres, earlier branches of the proboscidean family tree.
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Mastodons differed from mammoths in both appearance and diet. Their teeth were adapted for browsing on leaves, twigs, and shrubs, while mammoths possessed specialized grinding teeth suited for grazing on grasses. Gomphotheres were even more primitive and in some species possessed four tusks rather than two.

Together, these animals illustrate millions of years of proboscidean evolution and migration throughout North America.

What These Fossils Tell Us
The presence of mammoths and their relatives indicates that the landscapes of Anza-Borrego were once dramatically different from the modern desert. During portions of the Pliocene and Pleistocene, the region supported rivers, floodplains, woodlands, and grasslands capable of sustaining large herbivores.
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Proboscidean fossils help scientists reconstruct:
  • Ancient climates
  • Vegetation and habitats
  • Mammal migration routes
  • Evolutionary relationships among elephant relatives
  • The history of North American ecosystems
Because these animals occupied the top tier of herbivore communities, they serve as important indicators of environmental change through time.

Explore a Fossil in 3D
Rotate, zoom, and examine this specimen from the Anza-Borrego Desert State Park collections.
Interactive 3D Model: Mammuthus columbi
Specimen Information
  • Catalog Number: ABDSP3734 V9259
  • Element: Skull in jacket
  • 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 the most important late Cenozoic fossil records in North America. The park's mammoths, mastodons, and other proboscideans provide a unique window into the evolution of elephants and the changing landscapes of the American Southwest.

The discovery of the southern mammoth skeleton by George Miller and his team remains one of the most celebrated fossil discoveries in the history of the park and highlights the continuing scientific value of Anza-Borrego's fossil resources.

The Fossil Record
  • Gomphothere (Gomphotheriidae)
  • Stegomastodon
  • Southern Mammoth (Mammuthus meridionalis)
  • Columbian Mammoth (Mammuthus columbi)

Quick Facts
  • Group: Proboscidea
  • Includes: Mammoths, mastodons, gomphotheres, and elephants
  • Most famous species: Mammuthus meridionalis (southern mammoth)
  • Age: Pliocene and Pleistocene
  • Significance: One of the most complete southern mammoths known from North America
  • Location: Anza-Borrego Desert State Park, California






Learn More
Read Chapter 13, "Mammoths and Their Relatives," in Fossil Treasures of the Anza-Borrego Desert for a detailed discussion of proboscidean evolution and the remarkable mammoth discoveries from Anza-Borrego Desert State Park.