Zero-Sum vs Positive-Sum

Biological Parallel

Competition for a carcass is zero-sum—your gain is my loss, total calories fixed. But mycorrhizal networks are positive-sum—fungi extend tree root systems, trees provide sugars, both gain more than solo survival would allow. Mutualisms transform zero-sum resource contests into positive-sum partnerships: cleaner fish remove parasites (gain food), host fish gain health. Natural selection relentlessly favors positive-sum arrangements when available, which is why symbiosis is ubiquitous. The question isn't whether to cooperate, but whether the game structure allows mutual gains.