Small, isolated groups of Central American Indians are nearly 100% type O for the ABO blood system. This is best explained as being the result of: a
genetic drift
b
artificial selection
c
fitness
d
natural selection

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.

the answer is cell division : )