Fig. 3.

Evidence for peripheral and central circuit evolution in Heliothis moths. a Female pheromone blends of H. virescens and H. subflexa share major component A but differ in secondary components B–E. Circles or triangles represent compounds that promote or inhibit attraction, respectively, in conspecific and/or heterospecific females. A, (Z)-11-hexadecenal; B, (Z)-9-tetradecenal; C, (Z)-9-hexadecenal; D, (Z)-11-hexadecenol; E, (Z)-11-hexadecenyl acetate. b Schematic of the macroglomerular complex of each species. Glomerulus color indicates tuning for ligands in panel a. Symbols indicate valence—i.e., whether signaling in each glomerulus has a positive or negative effect on behavior. Note that glomerulus AM has negative valence in H. virescens but positive valence in H. subflexa, indicating there must be a change in downstream circuits.

Data are adapted from Vickers and Christensen (2003) and Baker et al. (2004)