Buttress roots: Why don't tall trees in the rain forest have deep roots? Because the water sits at the surface of the ground.
Because most nutrients are found at the surface of the soil.
Because most nutrients are found deep within the ground.

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 animal that would be cutest if scaled down to the size of a cat? elephant