Behavior rates for descenders (A), non-descenders (B) and controls (C) before and during the experimental trial. Behavior rates for descenders (A), non-descenders (B) and controls (C) before and during the experimental trial. Descender resident males decreased their dominance behaviors and increased subordinate behaviors after introduction of an intruder male. Non-descenders and control fish continued to perform dominance behaviors and no subordinate behaviors after the start of the trial. Data are plotted as means ± s.e.m., compiled into 5 min bins. Dominant behaviors (combined territorial and reproductive) (circles, solid lines) and subordinate behaviors (fleeing) (squares, dashed lines) are plotted at each time point. Minutes 0–4 represent the pre-trial period when the resident was interacting with the small community in the left compartment, and the shaded box at minutes 5–9 indicates placement of the left opaque barrier and introduction of the intruder at minute 5. Asterisks designate statistical differences between dominant and subordinate behaviors within each 5 min bin (P<0.05). N=12 fish per group per time point. Karen P. Maruska et al. J Exp Biol 2013;216:3656-3666 © 2013. Published by The Company of Biologists Ltd