The following paper is now available online: Insley, S.J. and Holt, M.M. 2012. Do male northern elephant seals recognize individuals or merely relative dominance rank? J. Acoust. Soc. Am. 131 (1), pp. EL35-41. Published Online 13 December 2011. The publication is available online at: http://link.aip.org/link/?JAS/131/EL35 Abstract: Vocal recognition was tested in a socially dynamic context where many individuals interact: the female defense polygyny practiced by male northern elephant seals. The goal was to tease apart whether animals recognize other individuals or instead use a simple rule-based category (i.e., relative dominance rank). A total of 67 playback experiments conducted with 18 males at An˜o Nuevo State Reserve, California, tested three aspects of recognition: (1) recognition of relative rank; (2) whether such recognition was continuous or categorical; and (3) recognition of familiarity. Results indicate that males recognize familiar individuals although responses are primarily based on relative dominance rank. © 2012 /Acoustical Society of America/