Peccaries and Javelinas of Anza-Borrego Desert State Park
Ancient Pig-Like Mammals of Southern California

Peccaries have been an important part of North American ecosystems for millions of years. Although they resemble pigs, peccaries belong to their own family, Tayassuidae, and are more closely adapted to the environments of the Americas. Fossils preserved in Anza-Borrego Desert State Park document several extinct species that lived during the Pliocene and Pleistocene, providing insight into the evolution of these hardy mammals and the changing environments of southern California.

The fossil record of Anza-Borrego shows that peccaries occupied a wide range of habitats, from river valleys and woodlands to expanding grasslands and open savannas, long before the modern desert developed.

Peccaries in Ancient Anza-Borrego
During the Pliocene and Pleistocene, Anza-Borrego supported several species of peccaries living alongside horses, camels, mammoths, deer, antelope, and ground sloths. They were common members of prehistoric herbivore communities and likely traveled in family groups much like modern javelinas.

As climates gradually became drier, peccaries adapted to changing vegetation and landscapes. Their fossils occur throughout much of the Park's terrestrial fossil record, making them useful indicators of environmental change through time.

Some species disappeared during the late Pleistocene, while others gave rise to lineages that survive today in the southwestern United States and Central and South America.

Platygonus — The Flat-Headed Peccary
The best-known peccary from Anza-Borrego is Platygonus, commonly known as the flat-headed peccary. This animal was somewhat larger than the modern collared peccary and possessed longer legs, making it well suited for traveling across open landscapes.

Unlike modern javelinas, which are often associated with desert scrub, Platygonus inhabited a variety of environments including woodlands and grasslands. Fossils from Anza-Borrego help document the geographic distribution of this successful Ice Age species across western North America.

Early Peccary Diversity
The fossil record of Anza-Borrego also preserves evidence of earlier peccary evolution. Several extinct genera occupied southern California during the Blancan and Irvingtonian North American Land Mammal Ages, demonstrating that peccaries diversified considerably before the appearance of the modern collared peccary.

These species illustrate how changing climates and vegetation influenced the evolution of hoofed mammals during the late Cenozoic.

What Peccary Fossils Tell Us
Peccary fossils help scientists reconstruct:

• Ancient grassland and woodland ecosystems
• The evolution of hoofed mammals in North America
• Climate and environmental change
• Herbivore communities of the Pliocene and Pleistocene
• The relationships between extinct peccaries and modern javelinas

Because peccaries are sensitive to vegetation and water availability, their fossil record provides valuable information about prehistoric habitats preserved within Anza-Borrego.

Why Anza-Borrego Matters
Anza-Borrego Desert State Park preserves one of North America's most complete late Cenozoic terrestrial fossil records. Fossil peccaries are an important component of that record, documenting the evolution of a successful group of hoofed mammals that occupied southern California for millions of years.

Together with horses, camels, deer, antelope, and other grazing mammals, peccaries help reconstruct the diverse herbivore communities that once flourished long before today's desert landscape emerged.

The Fossil Record

• Flat-headed peccary (Platygonus sp.)

Quick Facts
Family: Tayassuidae
Includes: Extinct peccaries and relatives of the modern javelina
Famous species: Platygonus
Age: Pliocene and Pleistocene
Role: Medium-sized herbivores and omnivores
Significance: Evidence for the evolution of North American peccaries and changing prehistoric environments
Location: Anza-Borrego Desert State Park, California

Learn More
Read Chapter 16, "The Smaller Artiodactyls: Peccaries, Oxen, Deer and Pronghorns," in Fossil Treasures of the Anza-Borrego Desert for a detailed discussion of the fossil peccaries and their role in the ancient ecosystems of Anza-Borrego Desert State Park.