Sedimentary models of fossil biomolecules, principles and methodological improvements

TL;DR

This paper introduces a sedimentary model for fossil biomolecules that considers environmental interactions and microstructure, improving the reliability of molecular analysis in paleogenomics.

Contribution

It presents a new molecular sedimentation model that integrates microstructure and environmental factors for better molecular inference in fossils.

Findings

Damage patterns are influenced more by burial environment than age.

Closed compartments preserve minimally damaged biomolecules.

Open reservoirs show extensive damage due to water exposure.

Abstract

Deamination has historically been important for authenticating ancient biomolecules. However, expanding paleogenomic datasets indicate that damage patterns are more influenced by burial hydrology and microstructural context than by molecular age or ancestry. Fossils interact with their environments differently: some form closed, water-restricted compartments that preserve minimally damaged endogenous biomolecules, whereas others serve as open molecular reservoirs in which infiltrated environmental biomolecules undergo extensive deamination from repeated water exposure. Reliance on deamination alone can therefore suppress endogenous signals and complicate the interpretation of exogenous sequences. By introducing the molecular sedimentation model for fossil biomolecules, this Perspective outlines a source tracing framework that integrates fossil microstructure, ecological reference sets, and species-specific fragments to enable more reliable molecular inference across diverse depositional environments.