This study investigates the biomechanical mechanisms underlying the adaptive evolution of residents’ consumption structures in response to the development of digital finance in China. Drawing on panel data from 31 provinces between 2012 and 2022, the analysis integrates concepts from behavioral biomechanics to interpret how digital finance enhances individual adaptability in rapidly changing technological environments. Empirical results from fixed effects and instrumental variable regressions reveal that digital finance significantly promotes consumption upgrading, shifting expenditure from survival to developmental and hedonic categories. This adaptive shift is mediated by improved income levels, expanded access to consumer credit, enhanced payment environments, and increased entrepreneurial and innovation activities. Heterogeneity analysis indicates stronger effects in high-income regions and economically developed eastern provinces. The study proposes that digital finance functions as a technological ecosystem that fosters behavioral flexibility, innovation, and resilience— paralleling adaptive mechanisms in biological systems.