This chapter examines adaptive diversification in language and religion. The historic record contains many examples of the types of diversification occurring in these models. Diversification in languages has been rampant throughout history, and must have often occurred under substantial contact between hosts of diverging language memes. Similarly, it seems clear that religious diversification has often occurred, and continuous to occur, under conditions of substantial contact. The models illustrate that diversifying processes should be expected to operate whenever the likelihood of secession from a dominant culture increases with increasing dominance of the mainstream culture. Intuitively, it is not hard to imagine that the attractiveness of a culture diminishes as the culture becomes more dominant, dogmatic, and perhaps oppressive, and that the desire to stand out and be different increases in increasingly conformist cultures.