ONLY 1 PERCENT of sunlight pierces the rain forest canopy. This is because in a rain forest the sunlight is blocked by the canopies formed by the densely growing trees and only a very small portion of sunlight reaches the surface of the rain forest. Thus, very little vegetation is found on the ground level of a rainforest.
The mutation is a substitution
Mexico .. if thats an option
Not as many people die at a young age therefore increasing the population and birth rate because more people are able to have children.