Evolution of pre-genetic semantic information in protocells under variable inheritance fidelity

Area of Science:

• Origins of Life Research
• Systems Chemistry
• Astrobiology

Background:

• Classical models (quasispecies, RNA-world) posit replication for information evolution.
• Prebiotic systems require a mechanism for heritable structure emergence.
• The origin of semantic information in early life is poorly understood.

Purpose of the Study:

• To investigate if semantic structure can arise in prebiotic systems without replication.
• To model the emergence of heritable information through compositional heredity.
• To determine the relationship between semantic information, inheritance fidelity, and adaptive function.

Main Methods:

• Developed a minimal agent-based protocell model with RNA-like oligomers and metabolites.
• Simulated protocell inheritance via noisy physical partitioning.
• Quantified semantic structure using mutual information between motif identity and metabolite class.
• Analyzed the impact of varying inheritance fidelity on semantic information and fitness.

Main Results:

• A sharp semantic threshold (approx. 0.7 fidelity) was identified for accumulating motif-metabolite correlations.
• Above this threshold, semantic information rapidly increased and stabilized as a heritable property.
• Meaningful structure emerged before significant fitness gains, indicating a pre-genetic information system.
• Compositional heredity alone can generate spatial organization and environmental semantics.

Conclusions:

• Semantic information and heritable structure can emerge in prebiotic systems without template-based replication.
• A pre-genetic information system based on compositional heredity provides a link to sequence-based evolution.
• This model offers a novel perspective on the early stages of life's origins, emphasizing meaning before function.