Artificial intelligence (AI), particularly powerful generative models and pervasive social algorithms, is intervening in cultural production, dissemination, and consumption in unprecedented ways, acting as a significant new force within the complex cultural ecosystems humans inhabit (a perspective aligned with the ecological turn, Kwok, 2025H). This paper proposes a theoretical framework for understanding AI's profound and potentially long-term influence on these ecosystems, examining its complex dual role: acting metaphorically and critically as both a potential catalyst for novel cultural variation and a powerful algorithmic filter shaping cultural transmission and selection dynamics. This impact extends far beyond mere efficiency gains, potentially reshaping meaning systems and core human values. Drawing critically on concepts heuristically adapted from cultural evolution theory (variation, selection, transmission), social network analysis, and computational social science, while continuously emphasizing the centrality of human agency (interpretation, resistance, adaptation), the specific computational nature of AI (pattern-based, lacking deep understanding, Kwok, 2025P), and the profound influence of structural power dynamics (political economy, platform control, digital colonialism, Kwok, 2025H) governing its deployment, this paper analyzes the mechanisms through which AI can influence the introduction of new cultural elements (styles, narratives, ideas) and significantly alter the propagation patterns of specific cultural traits. It explores potential long-term dynamical consequences for cultural symbols, narratives, aesthetic norms, value systems, collective memory practices, and shared meaning frameworks, paying particular attention to identifying potential pressures on dimensions of human "Existential Redundancy" (ER) (e.g., potentially marginalizing deep meaning generation, non-utilitarian creativity, or diverse aesthetic expression, Kwok, 2025F). The paper frankly acknowledges the significant empirical challenges in isolating AI's causal impact amidst complex, multi-causal cultural change and calls for methodologically pluralistic approaches. Furthermore, it critically analyzes the tangible socio-technical risk of "algorithmic cultural hegemony"-where platform-controlled algorithms reflecting specific commercial logics and concentrated power structures (Kwok, 2025H) might foster cultural homogenization or reinforce dominant global ideologies-emphasizing this as a phenomenon contingent on human choices, economic incentives, and structural forces, not an autonomous action by AI itself. Possibilities for human resistance, cultural hybridity, and the formation of alternative cultural niches within these structures are also explicitly acknowledged. Finally, the paper discusses the necessity, principles, inherent trade-offs, and significant structural barriers associated with designing more human-controllable, value-sensitive AI systems and implementing effective governance strategies (including structural interventions targeting platform power, promoting diversity, ensuring fair compensation for creators, and addressing international cooperation challenges) aimed at fostering healthier, more diverse, resilient, and equitable cultural ecosystems. It underscores the centrality of human agency (even as reshaped) and collective societal choices in navigating these complex processes, situating this analysis within the broader framework of the Existential Symbiosis Theory (Kwok, 2025R). This paper ultimately provides a critical analytical framework and a cautionary perspective, grounded in cultural evolutionary dynamics but critically informed by STS, political economy, computational limits (Kwok, 2025P), and a commitment to humanistic values (Kwok, 2025N), calling for rigorous, critical, and interdisciplinary research into AI's profound and unfolding cultural implications.