In death valley, california, there are several ponds that are formed in various areas of the desert. each pond contains its own species of fish unique to the pond it lives in.
a. geographic isolation
b. anatomical isolation
c. behavioral isolation
d. temporal isolation

A. Geographical Isolation

Explanation - Geographical Isolation alludes to the physical obstructions that exist that shield two species from mating. For instance, a types of monkey that is situated on an island can't breed with another types of monkey on the terrain.

The water separates the two species by keeping them secluded from each other and make it unthinkable for them to breed. In this case, fishes of different ponds cannot breed because they are separated from one pond to another.  

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.