Economics in nature is fascinating. There is always a balance or a balance sheet if you will. A cheetah has to make a kill once in every five tries or it will starve to death and not be able to have the energy for a sixth attempt.
When a species is lost to extinction another species adapts to fill the gap. Aminals divided by continents cause different species to like rolls of other species. In Australia, kangaroos fulfill the role of deer and other grazers.
So it is in every aspect of life including humans. Take politics. When an extreme party totally dominates and eradicates an opposing party, the body of the remaining party will slowly but ultimately split and start acting as two different parties that resemble the past parties.
We all contemplate what the world would be without religion. The fact is nature just won't allow that to happen. We may as a society eradicate what we know as religion, but a new entity will emerge to take its place.