Abstract
Mollusk shells were recently revealed as metagenomic archives of the past, potentially covering the last 100,000 years. This has not only opened new avenues for ancient DNA research but also added DNA to the list of morphological, structural and biogeochemical shell proxies that inform about the evolution, life history, stress responses and past environments of mollusks. Multi-proxy studies thus offer the unique opportunity to characterize, at high resolution, the dynamics of their different biological responses to environmental changes. Here, we focus on marine mussels as model organisms for eco-evolutionary studies. We combine 3D computed tomography imaging, statistical shape analyses, diffeomorphometry, paleo-environmental re-construction and ancient genomics. In a multi-disciplinary approach, to investigate the relationships between the shell morphology and genomic composition of wild Mytilus mussels across the Baltic Sea M. edulis x M. trossulus hybrid zone at both the spatial and temporal scales