Ward, Stacey M.Sánchez-Villagra, Marcelo R.Raymond, CaitlinLazaro, Gizéh Rangel-deLynch, SinéadWilson, Laura A. B.2026-07-192026-07-192589-0042RIS:urn:C010A1FD8715A00FEC753EE3E9349568WOS:001759220900001ORCID:/0000-0002-3779-8277/work/220850776ORCID:/0000-0003-1725-0172/work/220859570https://hdl.handle.net/1885/733813395For at least 10,000 years, people from many cultures have demonstrated social status or group affiliation by performing intentional cranial modification (ICM), altering head shape for life in early infancy. We present a database of ICM cases (n = 1,772) across the Americas, where this practice was prominent and widespread, and use spatial statistics to explore spatiotemporal variations in the prevalence of ICM in this region from a cultural evolutionary perspective. Prediction surfaces produced using Empirical Bayesian Kriging suggested that ICM first occurred in Central America. The spatial extent of this practice then broadened to encompass North and South Americas. Spatial analyses suggest that annular ICM cases appeared where tabular cases were present and its geographic range increased rapidly relative to tabular ICM. This suggests that annular ICM may be a derived cultural behavior and that existing familiarity with cranial modification behaviors aided the adoption of additional methods of head shaping.This work was supported by Swiss National Science Foundation ( SNF ) project number 208545 to M.R.S.-V. and Analía Forasiepi. L.A.B.W. is supported by the Discovery Program of the Australian Research Council ( FT200100822 ). G.R.-d.L. is supported by the Spanish Ministry of Science and Innovation and the European Social Fund (grant RYC2024-051368-I funded by MICIU/AEI/10.13039/501100011033 and by ESF+). We thank the anonymous reviewers for their suggestions, which helped improve this manuscript.16enPublisher Copyright: © 2026 The AuthorsAnthropologyArcheologyGeography2026-05-1510.1016/j.isci.2026.115643105037077350