Restrain is all over the place in nature. Unconstrained growth followed by starvation is the hallmark of primitive processes like fire and basic life forms.
Most individuals grow up to a genetically predetermined size. Colonies adapt their size to the amount of resources they have available, optimizing for long term perenniality.
The human economy behaves like a primitive life form, at the moment.
Ecosystems are usually resilient to such threats, but the fact we've been able to tap into fossil fuel gives us too large an advantage for them to strike back.
I'm not sure "restraint" is the correct word in the examples you cite. Individual size is typically the result of a combination of evolutionary selection pressure and physics. Colonies are constrained by resources which influence reproductive rates.
Everything in biology is the result of a combination of evolutionary selection and physics, I don't understand where you're going with that.
These are both instances of restraint hard-coded in DNA. Not growing/reproducing in some circumstances is part of the program.
Contrast it with cancer, or breakthrough, overaggressive infectious agents that kill their host quickly (but gradually give way to milder versions of themselves).
Some cancers grow so fast that part of the tumors die of necrosis (and off course most often the host ultimately dies).
Most individuals grow up to a genetically predetermined size. Colonies adapt their size to the amount of resources they have available, optimizing for long term perenniality.
The human economy behaves like a primitive life form, at the moment.
Ecosystems are usually resilient to such threats, but the fact we've been able to tap into fossil fuel gives us too large an advantage for them to strike back.