One reason for an increase in tensions in west africa was

the spread of Islam

Explanation:

The spread of Islam at times created tensions between the populations already living in North Africa and West Africa and the Muslim groups who were coming into the area. Some of these Muslim groups started wars against the natives, whom they viewed as godless pagans.

aren't cheetos good enough to be president?

it depends on which society you are referring to. many civilization performed rituals so the gods would with their growing season but the most well known is that of the aztecs. they would make sacrifices, usually animals, but sometimes humans as well.