Peccaries have scent glands below each eye and another on their backs, though these are believed to be rudimentary in "P. maximus". They use the scent to mark herd territories, which range from . They also mark other herd members with these scent glands by rubbing one against another. The pungent odor allows peccaries to recognize other members of their herd, despite their myopic vision. The odor is strong enough to be detected by humans, which earns the peccary the nickname of "skunk pig".