The number or variety of species found in a particular area is called

Answer;

Species diversity

Species diversity  is the umber of variety of species in the world or in a particular region.

Explanation;

-Species diversity is the number of different species that are represented in a given community.

-Species diversity is measured based on two main factors, which are; richness and evenness. Richness is a measure of the number of different kinds of organisms present in a particular area. For instance, species richness is the number of different species present. Evenness on the other hand, compares the similarity of the population size of each of the species present.

sorry, but you do not have posted the diagram.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".