Wild man syndrome experiencing the condition. Some theorists believe that emotions are produced by culture and are not biological. Their emotional diversity across cultures and the way individuals think is based on their social environment and on past and future experience and expectations. Wild Pig syndrome is unusual by Western standards; however, it is common and normal in the Gururumba tribe. This syndrome got its name from the occurrence of domesticated pigs going through a temporary state in which the pig will run wild. With appropriate measures the pig can return to the domesticated pig life among the villagers. This is similar to
The Call of the Wild on trust and love. Writing in the "Introduction" to the Modern Library edition of "The Call of the Wild", E. L. Doctorow says the theme is based on Darwin's concept of survival of the fittest. London places Buck in conflict with humans, in conflict with the other dogs, and in conflict with his environment—all of which he must challenge, survive, and conquer. Buck, a domesticated dog, must call on his atavistic hereditary traits to survive; he must learn to be wild to become wild, according to Tina Gianquitto. He learns that in a world where the "club and the fang"