General linear model results for the proportion of aphids parasitized (arcsin-square root transformed).

Separate analyses are presented for all three treatments (a) and for the control and 35°C heat shock treatments only (b), because the high mortality after the 39°C heat shock rendered those results less reliable. The analyses were conducted once for all aphid sublines and once restricted to the Hamiltonella defensa-infected sublines, because only in the latter case does the aphid subline x parasitoid line interaction strictly reflect the G x G interaction between the parasitoids and the hosts' symbionts.