Background Information: Major deserts- Sahara and Sahel Importance of tsetse fly- Its presence prevented Africans from using cattle, donkeys, and horses to farm near the rain forests and it prevented invaders from colonizing. Animism- A religion in which spirits play an important role in regulating daily life. Importance of griots- No written language so the stories were told orally by griots. A lot of African leaders adopted Islam in the 11th century. The Soninke people in Ghana had 2 important trade items: gold and salt. Islam was spread south of the Sahara in the 11th century throught trade.