Initiative, Personality and Leadership in Pairs 41. Rands SA (2010) Group-movement ‘initiation’ and state-dependent decision- making. Behavioural Processes 84: 668–670. 42. King AJ (2010) Follow me! I’m a leader if you do; I’m a failed initiator if you don’t? Behavioural Processes 84: 671–674. 43. Borg B, Bornestaf C, Hellqvist A, Schmitz M, Mayer I (2004) Mechanisms in the photoperiodic control of reproduction in the stickleback. Behaviour 141: 1521–1530. PLoS ONE | www.plosone.org 7 May 2012 | Volume 7 | Issue 5 | e36606