Fig. 3. Amino acids that increased on solitarization in final instar nymphs. (A) Amino acids that exhibited large (over 2x) rapid changes. Aspartate, glutamate and glycine showed rapid increases on the initial 24 h isolation of gregarious locusts, before declining again in the first stadium of isolation. Amounts increased again over a further 1–3 generations of isolation. Crowding third generation isolated locusts led to a rapid decline in the first 4 h, but amounts had increased third generation isolated values by 24 h of crowding. Values returned towards long-term gregarious values after 1 crowded stadium. (B) Amino acids that exhibited smaller (maximum 1.8x) and slower changes. Taurine, arginine and GABA did not change significantly during the first 24 h of crowding or isolation, but increased only after 1 generation of isolation. Values (mean ± S.E.M.) are sum amounts in the three sampled regions of the central nervous system, standardized to give the mean long-term gregarious value as 1. Stages as in Fig. 1.