What is one task that a peer reviewer is not likely to participate in?

A peer reviewer is not likely to be responsible for making the coffee or replacing the light bulbs in his laboratory.  

He is a "peer" (equal) of the scientist who published the research that he has been asked to review.  So he's likely to be one of the higher-ups in his own organization.

Africans having pride in their own culture despite being ruled by people of different cultures gave them a sense of self worth.

Explanation:

The people of Africa were ruled by people of different cultures and by the people from different countries. They had a history of colonial rule where they were a colony of many countries.

But despite being ruled by people of different cultures, the people of Africa had pride in their own culture. This gave these people a sense of self worth. The Africans had pride in their own culture, in their own language and their own nation.