Figure 3. BAG neurons are required for some but not all host-seeking behaviors.

A. Volatiles released by live waxworms (Galleria mellonella), crickets (Acheta domesticus), mealworms (Tenebrio molitor), and superworms (Zophobas morio) attract the parasitic IJs but not C. elegans dauers. n = 6–27 trials. B. Insect volatiles also stimulate jumping by S. carpocapsae. n = 3–11 trials. **, P<0.01, one-way ANOVA with Dunnett’s post-test. For A–B, error bars represent SEM. C. BAG neurons are required for chemotaxis toward waxworms in H. bacteriophora. n = 10–38 worms for each treatment. **, P<0.01, Fisher’s exact test. D. BAG neurons are not required for jumping evoked by waxworm odors in S. carpocapsae. n = 20–39 worms for each treatment. No significant differences were observed between treatment groups. For C–D, values shown represent the percentage of worms that yielded a positive behavioral response; error bars are not present because each worm was scored once individually. AWC or ASI chemosensory neurons were ablated as controls. E–F. Attraction of H. bacteriophora (E) and S. carpocapsae (F) to G. mellonella is eliminated and A. domesticus is reduced when CO₂ is chemically removed from host headspace using soda lime. n = 6–14 trials for each treatment. ***, P<0.001; **, P<0.01; *, P<0.05, Mann-Whitney or unpaired t test (host vs. host + soda lime). See also Figure S3.