Like their cousins, peccaries have designated areas within their home range for sleeping, foraging, and even defecating. Peccaries are known to be fiercely loyal to one another. Hunters tell tales of being forced into the tree-tops for sometimes days after shooting an animal travelling in the front of a herd. Mating behavior in peccaries is not well known. Both male and female peccaries reach sexual maturity at approximately one year of age.
Females are polyestrous, that is, they are sexually receptive all year around.
The litter size is usually small, 1-2 piglets. Distribution of Tayassuidae. The interlocking mechanism, however, restricts lateral jaw movement, hence peccaries are unable to chew 'cud', a behavioral characteristic typical of other artiodactyls. Both anatomical and molecular characters suggest that the white-lipped and the chacoan peccaries are closely related to one another. The chacoan peccary is considered to be the most primitive of the living forms, resembling the extinct form, Platygonus .