Humans have done many good things, but they have done many bad things and most of them are hurting the Earth. In this cause they are hurting the environment and don't know it. We destroy nature to only get food, resources, wood, and many other things such as we hunt for food and that can cause a species to be endangered or extinct, it can even cause it's prey to over populate. In the Savanna many trees are dying. Us humans are replacing special trees for crops. Humans have brought many new types of animals to the Savanna, when they aren't adapted to the conditioning of the Savanna. Some new animals will die if they aren't in their natural habitat. Some people even start fires on purpose and don't try to turn the fire off. This kills the plants and they will never grow again. Some people do it on accident and still doesn't help. Some people actually do turn the fire off but the plants still get the same effects. So we got to consider all this to not hurt nature.