The Law of the Jungle as Earth’s Universal Selection Principle

Abstract

Earth’s four‑billion‑year evolutionary trajectory can be unified under a single selection principle: with limited resources, variants that convert those resources into persistence, replication, or control more efficiently expand, while others disappear. This manuscript argues that the “law of the jungle” is not a metaphor for animal behavior but the universal mechanism governing competition across chemistry, biology, ecology, and human civilization. Prebiotic molecules, protocells, organisms, ecosystems, and societies all evolved through differential resource conversion shaped by physical constraints. Mass extinctions acted as environmental resets, eliminating even dominant species when conditions shifted faster than their traits could adapt. In the modern era, human civilization represents the fourth jungle, where competition manifests through agriculture, markets, technology, warfare, and geopolitics. Recent discussions of interstellar travel and planetary colonization do not escape this law: the extreme distances of space, the fragility of long‑term life‑support systems, the physiological collapse caused by low gravity, and the meteorite bombardment on planets like Mars render large‑scale human expansion beyond Earth physically impossible. Replicator dynamics formalizes this universal rule mathematically, showing that variants with above‑average fitness inevitably rise in frequency. Across all scales, the environments changed and the players changed, but the law did not. The driving force behind Earth’s evolution—and humanity’s future—is relentless competition shaped by constraint.