DelBarco-Trillo, JavierGreene, Lydia K.Goncalves, Ines BragaFenkes, M.Wisse, Jillian H.Drewe, J.A.Manser, Marta B.Clutton-Brock, Tim H.Drea, Christine M.2016-01-152016-02DelBarco-Trillo, J, Greene, LK, Goncalves, IB, Fenkes, M, Wisse, JH, Drewe, JA, Manser, MB, Clutton-Brock, T& Drea, CM 2016, 'Beyond aggression : androgen-receptor blockade modulates social interaction in wild meerkats', Hormones and Behavior, vol. 78, pp. 95-106.0018-506X (print)1095-6867 (online)10.1016/j.yhbeh.2015.11.001http://hdl.handle.net/2263/51195Inmale vertebrates, androgens are inextricably linked to reproduction, social dominance, and aggression, often at the cost of paternal investment or prosociality. Testosterone is invoked to explain rank-related reproductive differences, but its role within a status class, particularly among subordinates, is underappreciated. Recent evidence, especially for monogamous and cooperatively breeding species, suggests broader androgenic mediation of adult social interaction.Weexplored the actions of androgens in subordinate, male members of a cooperatively breeding species, the meerkat (Suricata suricatta). Although male meerkats show no rank-related testosterone differences, subordinate helpers rarely reproduce.Weblocked androgen receptors, in the field, by treating subordinate males with the antiandrogen, flutamide. We monitored androgen concentrations (via baseline serum and timesequential fecal sampling) and recorded behaviorwithin their groups (via focal observation). Relative to controls, flutamide-treated animals initiated less and received more high-intensity aggression (biting, threatening, feeding competition), engaged in more prosocial behavior (social sniffing, grooming, huddling), and less frequently initiated play or assumed a ‘dominant’ role during play, revealing significant androgenic effects across a broad range of social behavior. By contrast, guarding or vigilance and measures of olfactory and vocal communication in subordinate males appeared unaffected by flutamide treatment. Thus, androgens in male meerkat helpers are aligned with the traditional trade-off between promoting reproductive and aggressive behavior at a cost to affiliation. Our findings, based on rare endocrine manipulation in wild mammals, show a more pervasive role for androgens in adult social behavior than is often recognized, with possible relevance for understanding tradeoffs in cooperative systems.en© 2015 Elsevier Inc. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Hormones and Behavior. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Hormones and Behavior, vol. 78, pp. 95-106, 2016. doi :10.1016/j.yhbeh.2015.11.001.AntiandrogenFlutamideTestosteroneAggressionCommunicationProsocial behaviorBehavioral neuroendocrinologySubordinate maleField experimentCooperative breederBeyond aggression : androgen-receptor blockade modulates social interaction in wild meerkatsPostprint Article