Dear MARMAM community, On behalf of my coauthors, I'm pleased to announce the recent publication<https://www.pnas.org/doi/10.1073/pnas.2201692119> of our paper, "Evidence from sperm whale clans of symbolic marking in non-human cultures", in PNAS. Briefly, we show quantitative evidence that identity codas function as symbolic markers of cultural identity among seven Pacific Ocean sperm whale clans. We also characterize the distribution of clans in the Pacific and highlight similarities with human ethnolinguistic groups. If you would like a copy of the paper or have questions about our findings, please feel free to reach out to me via email (taylor.hersh@mpi.nl) or ResearchGate<https://www.researchgate.net/profile/Taylor-Hersh>. The abstract and author list is included below. Thank you for your interest! Taylor Hersh Postdoctoral Researcher, Comparative Bioacoustics Group Max Planck Institute for Psycholinguistics taylor.hersh@mpi.nl @taylorahersh Abstract: Culture, a pillar of the remarkable ecological success of humans, is increasingly recognized as a powerful force structuring nonhuman animal populations. A key gap between these two types of culture is quantitative evidence of symbolic markers—seemingly arbitrary traits that function as reliable indicators of cultural group membership to conspecifics. Using acoustic data collected from 23 Pacific Ocean locations, we provide quantitative evidence that certain sperm whale acoustic signals exhibit spatial patterns consistent with a symbolic marker function. Culture segments sperm whale populations into behaviorally distinct clans, which are defined based on dialects of stereotyped click patterns (codas). We classified 23,429 codas into types using contaminated mixture models and hierarchically clustered coda repertoires into seven clans based on similarities in coda usage; then we evaluated whether coda usage varied with geographic distance within clans or with spatial overlap between clans. Similarities in within-clan usage of both “identity codas” (coda types diagnostic of clan identity) and “nonidentity codas” (coda types used by multiple clans) decrease as space between repertoire recording locations increases. However, between-clan similarity in identity, but not nonidentity, coda usage decreases as clan spatial overlap increases. This matches expectations if sympatry is related to a measurable pressure to diversify to make cultural divisions sharper, thereby providing evidence that identity codas function as symbolic markers of clan identity. Our study provides quantitative evidence of arbitrary traits, resembling human ethnic markers, conveying cultural identity outside of humans, and highlights remarkable similarities in the distributions of human ethnolinguistic groups and sperm whale clans. Authors: Taylor A. Hersh, Shane Gero, Luke Rendell, Mauricio Cantor, Lindy Weilgart, Masao Amano, Stephen M. Dawson, Elisabeth Slooten, Christopher M. Johnson, Iain Kerr, Roger Payne, Andy Rogan, Ricardo Antunes, Olive Andrews, Elizabeth L. Ferguson, Cory Ann Hom-Weaver, Thomas F. Norris, Yvonne M. Barkley, Karlina P. Merkens, Erin M. Oleson, Thomas Doniol-Valcroze, James F. Pilkington, Jonathan Gordon, Manuel Fernandes, Marta Guerra, Leigh Hickmott, and Hal Whitehead