Figure 1. C. elegans behavioral responses to bacteria unfold over multiple time scales.

C. elegans consume diverse bacteria that differ in their nutritive qualities and their pathogenicity. Innate recognition of bacteria allows animals to generate rapid behavioral responses to bacterial odors and textures (left). After bacteria are ingested, animals undergo internal state changes that underlie long-lasting behavioral changes (middle). These long-lasting changes include alterations in their foraging strategies (right) and learned changes in bacterial preference.