Proteins can denature at extreme temperatures, or denature when inhibits are present. When this happens their functionality is dramatically reduced.
This would cause the overpopulation in the grassland preserve. There would be too many antelopes and zebras that they would have to compete for survival. The food resources would run out for both species and cause a competition among every animal.
You and that friend would eventally start runing out of food, then its competition. You'll have to fight over it survival of the fitest