a Measurements of galls and pupae of Barbotinia oraniensis and Parnips nigripes (F = female, M = male). Galls containing females are larger than galls containing males (ANOVA: F = 8.075, df = 1, p = 0.006) but galls attacked by Parnips do not differ in diameter from normal Barbotinia galls (p = 0.51) b Female pupae are heavier than male pupae (F = 18.35, df = 1, p < 0.0001) but Barbotinia pupae do not differ in weight from Parnips pupae (p = 0.90) c Barbotinia galls attacked by Parnips have relatively thicker walls than normal galls (F = 6.98, df = 1, p = 0.01) both in females and males. Barbotinia females n = 20, males n = 18, Parnips females n = 27, males n = 15.