Ever wonder why there are fights over territories, mates, food, water? Even trees fight other trees for the groundwater. Even when pet dogs have abundant food supply, they still hoard as much as they can when they are given something to eat and not hungry. It is just unsaid in nature because obv there are no agreements, MoUs, or money involved. When a Tiger has control over a territory, most other Tigers agree to it until some other challenges it.

all work in tandem

It is the ecosystem that works in tandem when you zoom out from an individual living being level.