The genetic structure of aphid populations has received increasing attention as a result of the evolution of insecticide resistance, the appearance of biotypes overcoming plant resistance and the increasing spread of aphid-born viruses. How can they manage to use different hosts and overcome insecticide and plants' morphological barriers? Recently, plasticity has been given more attention in ecological and evolutionary contexts as a specific adaptation to environmental variability. Phenotypic variation is crucial to a comprehension of evolutionary mechanisms, especially phenotypic host race formation and sympatric speciation in aphids. It is becoming clear that phenotypic plasticity is a fundamental component of evolutionary change and is one solution to the problem of adaptation to heterogeneous environments.

The genetic structure of aphid populations has received increasing attention as a result of the evolution of insecticide resistance, the appearance of biotypes overcoming plant resistance and the increasing spread of aphid-born viruses. How can they manage to use different hosts and overcome insecticide and plants' morphological barriers? Recently, plasticity has been given more attention in ecological and evolutionary contexts as a specific adaptation to environmental variability. Phenotypic variation is crucial to a comprehension of evolutionary mechanisms, especially phenotypic host race formation and sympatric speciation in aphids. It is becoming clear that phenotypic plasticity is a fundamental component of evolutionary change and is one solution to the problem of adaptation to heterogeneous environments.