ESSDD Earth System Science Data Discussions ESSDD Earth Syst. Sci. Data Discuss. 1866-3591 Göttingen, Germany 10.5194/essd-2026-458 PhaFoS: A Global Database of Phanerozoic Foraminiferal Size Feng Yan 1 Lai Jiankang 2 Chu Daoliang 2 Liu Xiaokang 2 Shu Xiang 2 Liow Lee Hsiang https://orcid.org/0000-0002-3732-6069 3 4 Wu Yuyang 5 Huang Yunfei 1 Song Haijun https://orcid.org/0000-0002-2721-3626 2 School of Geosciences, Yangtze University, Wuhan, China State Key Laboratory of Geomicrobiology and Environmental Changes, School of Earth and Planetary Sciences, China University of Geosciences, Wuhan 430074, China Natural History Museum, University of Oslo, Oslo 0562, Norway Centre for Planetary Habitability, Department of Geosciences, University of Oslo, Oslo 0371, Norway State Key Laboratory of Geomicrobiology and Environmental Changes, College of Marine Science and Technology, China University of Geosciences, Wuhan 430074, China 26 08 2026 2026 1 30 Copyright: © 2026 Yan Feng et al. 2026 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://essd.copernicus.org/preprints/essd-2026-458/ The full text article is available as a PDF file from https://essd.copernicus.org/preprints/essd-2026-458/essd-2026-458.pdf

Body size is a key phenotypic trait of living organisms, reflecting ecological function and individual metabolism. Evolutionary changes in body size also provide information on interactions between the organisms and their changing physical and biotic environments. Despite the utilitarian value of body size for understanding evolution and past environments, we lack a standardized, occurrence-based, Phanerozoic body size database for most groups of organisms, limiting large-scale studies of size evolution and size-environment interactions. Foraminifera are an ideal group to fill this data gap, given their abundant fossil record, extensive palaeogeographic distribution, and sensitivity to environmental changes. Here, we present PhaFoS, short for <u>Pha</u>nerozoic <u>Fo</u>raminifera <u>S</u>ize database. PhaFoS compiles 118,885 specimens, of which 103,121 from 963 published papers and the remaining 15,764 from our field colletions, representing 4,167 genera and 34,256 species. Each record is linked to standardized and queryable metadata fields, including test volume (log₁₀ &mu;m&sup3;), taxonomy, stratigraphic age, and both modern and paleogeographic coordinates. This database can be used to quantify temporal and spatial patterns of foraminiferal body-size over the Phanerozoic, and to explore the body size relationships with environmental conditions and their changes. The data files described in this paper are available at <a href="https://doi.org/10.5281/zenodo.20777319" target="_blank" rel="noopener">https://doi.org/10.5281/zenodo.20777319</a> (Feng et al., 2026).