Charitable effects on the environment.
This is something I discovered 25+ years ago and it provided the tipping point for me leaving religion. It is one thing that very few think of and this is the first link I have seen that deals with this issue. It is something from Greta's part of the world (she is shown). [overpopulation-project.com]
The research has not stopped, here is an update. "The problem is not the population growth, its preconcieved notions"