<p>Although the theory of evolution has explained “how” natural selection operates, the fundamental “why” still requires integration with thermodynamic principles. The second law of thermodynamics (total entropy increase in isolated systems) establishes universal directionality for natural processes but remains ambiguous regarding path selection, a critical gap addressed by the fourth law of thermodynamics. This law proposes that nonequilibrium systems, when presented with multiple pathways, will select those that maximize the rate of entropy production under existing constraints. This principle extends from physical systems to biological evolution: genetic mutations produce organisms with differential entropy production capacities, whose coexistence creates a dynamic network of pathways. Natural selection presents itself as the biological manifestation of the fourth law of thermodynamics, persistently favoring pathway combinations that achieve optimal entropy production rates. These thermodynamic selection pressures drive evolutionary progression through continuous genetic mutations and environmental feedback, where accumulated genetic information enables increasingly efficient entropy production strategies. By conceptualizing evolution through the thermodynamic framework, this perspective integrates biological natural selection with universal thermodynamic principles, offering a unified explanation for the origin and evolution of life.</p>