Few species are more social than pigs. They are quite gregarious and cooperate with and defend one another. Adults in the entire social group will protect a piglet, leaving food or their own litters to defend the endangered youngster. If one pig starts to dig out tree roots, others will invariably join in. Touch and bodily contact are especially important.
Pigs seek out and enjoy close contact and lie close together when resting.
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.