Figure 3.

EAG response to odourants tested at different humidity levels, for Coenobita clypeatus (a) and Drosophila melanogaster (b). A first recording session, including the odourants and concentrations to be tested, was performed at the initial high humidity (dark blue, 86–91% RH), a second at the low humidity (orange, 32–35% RH) and finally, a third at the high humidity level (final high humidity—light blue, 86–91% RH). (a) For C. clypeatus, four odourants were presented at dilutions from 10⁻⁴ to 10⁻¹ in each recording session (n = 5, error bars represent s.e.m. asterisk (*), p < 0.05-values based on repeated measurement ANOVA, followed by Tukey–Kramer multiple comparisons test). (b) For D. melanogaster, three odourants were presented at 10⁻¹ dilution in a recording session (no significant differences between responses at the different humidity levels, tested with repeated measurement ANOVA; error bars represent s.e.m., n = 6).