They also enjoy close contact with people familiar to them and will roll over to have their bellies rubbed. Pigs are very vocal and communicate constantly with one another. More than twenty of their vocalizations have been identified. They have an elaborate courtship ritual, including a song between males and females. Newborn piglets learn to run to their mother's voice, and the mother pig sings to her young while nursing.
Pigs also enjoy music.
When ready to give birth, the sow selects a clean, dry area apart from the group, sometimes walking several miles to search for a good nest site and to gather preferred bedding materials. She hollows out a depression in the ground and lines it with grass, straw, or other materials. For several days after her babies are born, she defends the nest against intruders. When her babies are five to ten days old, she encourages them to leave the nest to socialize with the other pigs. Weaning occurs naturally at three months of age, but young pigs continue to live with their mothers in a close family group.