Fig. 5.

Relationship of size dimorphism to male-male competition in C. columbae (lice illustrations not to scale). When males of different sizes were combined with a single female in mating arenas, typical sized males spent more time copulating than relatively small (A) or large (C) males; Paired Wilcoxon signed-rank tests: n = 10, S = 24.50, P = 0.02 for A, and n = 10, S = 22.50, P = 0.03 for C. When males of the same (typical) size were combined with a single female (B), the males did not differ significantly in copulation time; n = 10, S = 13.00, P = 0.25. Different letters indicate significant differences for P < 0.05.