Prebiotic oligomerization of amino acids: A step in molecular evolution toward biological complexity

Amino acids were produced abundantly on the early Earth through multiple endogenous and exogenous processes. However, their transition into stable oligomers remains poorly understood because most experimental studies have examined variables separately such as ionizing radiation, magnetic fields or environmental cycles without considering their combined effects. This work proposes that prebiotic oligomerization may have arisen under the joint influence of a varied and fluctuating environment operating far from equilibrium, where molecular heterogeneity, mineral surfaces and changing energy inputs acted in an integrated manner favoring processes of synthesis, degradation and selection. Based on the available experimental evidence, two complementary theoretical models are presented. The first describes molecular evolution as an expanding and self-organizing system. The second positions amino acid oligomerization as a transitional step within that evolutionary trajectory. Together, these models offer a perspective for analyzing molecular evolution by examining how interactions among environmental fluctuations, surface dynamics and mechanisms of molecular stability can sustain the emergence of persistent oligomeric structures and contribute to the early organization of chemical networks. Finally, implications are outlined that may be evaluated through experiments and simulations aimed at assessing the combined influence of these variables on emerging molecular complexity.