T. pecari is dark reddish brown to black and has white on the sides of the jaws. The name javelina is derived from the Spanish word for javelin or spear and refers to the sharp tusks of these animals. Peccaries live in a great variety of habitats, including desert scrub, arid woodland, and rainforest. They usually shelter in a thicket or under a large boulder. Limestone caves often serve as winter quarters in some areas.
Most activity is at night or in the cooler hours of the day.
Both species are known to use wallows in the mud or dust. The speed, agility, and group defense of peccaries render them more than a match for dogs, coyotes, and even bobcats. They often clash their canine teeth together as a warning. When fleeing danger, they move with a fast running gait. They have poor vision and fair hearing.