Fig. 8. The spatio-temporal pattern of the equivalent electromotive force along development was studied using the multiple air gap technique [a procedure that allowed the identification of the generation site of the different waveform components of the electric organ discharge (EOD) (Caputi et al., 1993)]. (A) The 30 mm fish exhibited a three-phase EOD with a slow early negative component generated at the abdominal region, a positive component generated all along the body, and a late negative component generated at the tail region. (B) The last component to appear (V₂) was clearly identified in the fish of 47 mm length (second trace, arrowhead) and was completely developed in (C) the juvenile of 68 mm length. Note the progressive reduction of the EOD duration and the relative increase of the late negative component (V₄).