Paleontologists map 540 million years of marine fossils to guide future digs

Paleontologists Thomas A. Neubauer of the Bavarian State Collections of Natural History and Mathias Harzhauser of Vienna's Natural History Museum built a global map of where shallow-marine fossils have been found and where gaps remain. The work analyzes 540 million years of fossil occurrences and pairs them with rock formations that could preserve ancient life. The aim is to steer scarce field resources toward places where accessible geology and missing data point to the highest potential for new finds.

The team used the Paleobiology Database, the main open repository of published fossil occurrences, to reconstruct where shallow-marine species have been documented across deep time. They then compared those records with the Macrostat database, which tracks geological formations and their suitability for fossil preservation. The analysis found that the Palaeozoic and Early Mesozoic are already heavily sampled, while Cenozoic shallow-marine deposits from the past 66 million years show the largest remaining opportunity for new species and ecosystem evidence.

The study's methods note is important: it is a database analysis, not a new excavation, using accumulated published records and geological suitability data rather than a defined field sample. That makes it a planning tool, not proof of hidden fossils. Still, it reframes a familiar problem: the fossil record is not just incomplete, it is unevenly sampled, with centuries of collecting concentrated in some regions and periods.

For researchers, the map is intended to reduce guesswork in choosing expedition sites where rock is exposed and the analysis identifies higher discovery potential. For broader science, it links geology, climate history and biodiversity, sharpening how Earth's past resilience is reconstructed. The real-world stake is efficient use of limited research resources and a clearer baseline for comparing ancient marine ecosystems with modern oceans.