Dear Colleagues, On behalf of my co-authors, I am happy to announce our recent publication in'Behavioral Ecology and Sociobiology': Extreme ecological constraints lead to high degree of individual stereotypy in the vocal repertoire of the Cape fur seal (/Arctocephalus pusillus pusillus/) Mathilde Martin, Tess Gridley, Simon Harvey Elwen, Isabelle Charrier BES (2021), https://doi-org.proxy.scd.u-psud.fr/10.1007/s00265-021-03043-y <https://doi-org.proxy.scd.u-psud.fr/10.1007/s00265-021-03043-y> Abstract: The ability to recognize the identity of conspecifics is a key component for survival of many animal species and is fundamental to social interactions such as parental care, intra-sexual competition or mate recognition. In group-living species, the simul- taneous co-existence of many individuals increases the number of interactions and reinforces the need for individual recogni- tion. Acoustic signals are widely used by birds and mammals to communicate and to convey information about identity, but their use in very dense colonies becomes challenging due to the high level of background noise and the high risk of confusion among individuals. The Cape fur seal (CFS) is the most colonial pinniped species and one of the most colonial mammals in the world, with colonies of up to 210,000 individuals during the breeding season. Here, we investigated the individual stereotypy in vocalizations produced by pups, females and male CFS using Random Forests and index of vocal stereotypy (IVS). We thus compared IVS values of CFS to other pinniped species. Within CFS we identified individuality in all call types but the degree of individual stereotypy varies in regard to their social function: affiliative calls produced in a mother–pup reunion context and territorial calls produced by mature bulls holding harem were more individualized than vocalizations involved in agonistic inter- actions. Our inter-species comparisons among pinnipeds showed that CFS affiliative and territorial calls displayed higher degrees of individuality compared to other species with similar or lower ecological constraints (colony density and social structure). Please feel free to email me for a pdf copy at:mathilde.martin@universite-paris-saclay.fr <mailto:stephanie.ploen@gmail.com> -- *Mathilde MARTIN* PhD Student Acoustic Communications Team, Department Cognition & Network Neuroscience NeuroPSI - Paris-Saclay Institute of Neuroscience Rue Claude Bernard, Bat. 446, 91405 Orsay, FRANCE https://neuropsi.cnrs.fr Tel: +33 (0)1 69 15 49 63 Email: mathilde.martin@universite-paris-saclay.fr Website: https://mathildemartin-research.com/