Figure 3.

(A) The competitive serotonin (5HT) synthesis inhibitor alpha-methyl-tryptophan (AMTP) has no effect on the frequency of threat display in response to male-AS. Data are given for socially naive crickets (white bars), winners (black bar), and losers (gray bar). Significant differences between data sets are indicated by asterisks [χ² test, Bonferroni correction to alpha for two comparisons: ^*p < 0.025; ^**p < 0.005; n is given above the x-axis in (A)]. (B) Frontal sections of a male cricket's brain showing 5HT-like immunoreactive (5HT-ir) staining of the central body (CB): (Bi) from a control cricket, (Bii) a corresponding section from a cricket 7 days after abating both antennae.