The Cretaceous Diatom Database: A tool for investigating early diatom evolution.

Area of Science:

• Paleontology
• Evolutionary Biology
• Marine Biology

Background:

• Diatoms first appeared in the Cretaceous fossil record, providing direct evidence of their early evolution.
• The fossil record is incomplete, necessitating extrapolation through time-calibrated phylogenies for understanding early diatom evolution.
• Early diatom evolution remains poorly understood due to limitations in fossil data and phylogenetic analyses.

Purpose of the Study:

• To compile the first comprehensive Cretaceous Diatom Database for investigating early diatom taxonomy, diversity, and occurrence.
• To identify well-documented Cretaceous diatom fossils suitable for calibrating molecular clocks in phylogenetic analyses.
• To enhance the integration of fossil data with molecular phylogenies for a more robust understanding of diatom evolution.

Main Methods:

• Compilation of the Cretaceous Diatom Database, integrating fossil occurrences and taxonomic information.
• Selection and documentation of key Cretaceous diatom fossils for molecular clock calibration.
• Comparative analysis of fossil data and the compiled database to assess Cretaceous diatom diversity.

Main Results:

• The Cretaceous Diatom Database provides a comprehensive resource for studying early diatoms.
• Analysis revealed substantially greater Cretaceous diatom diversity than previously estimated.
• A curated list of Cretaceous fossils suitable for molecular clock calibration was identified.

Conclusions:

• The Cretaceous Diatom Database is a valuable resource for evolutionary and taxonomic studies of diatoms.
• The study highlights the need for further taxonomic work on Cretaceous diatoms.
• The identified fossils are crucial for calibrating molecular clocks and refining diatom evolutionary timelines.