After forest fire in the La-Sal mountains, an ecologist notes that the species present after 5 years was different than the species present after 25 years, and after 75 years were different than those after 25 years. What are the general characteristics of the species at each stage, why does the community change over time?After forest fire in the La-Sal mountains, an ecologist notes that the species present after 5 years was different than the species present after 25 years, and after 75 years were different than those after 25 years. What are the general characteristics of the species at each stage, why does the community change over time?