Analysis of correlations of learning scores in controls and treated bees.

H0 indicates the null hypothesis being tested. R2 represents the adjusted correlation factor of the linear regression. For each comparison, the corresponding Figure number is given. There is a strong correlation between the learning scores of control bees and bees treated with IPA; all groups showed significant learning, as described earlier. In bees displaying Type 1 responses (Fig 4A), the slope of the regression line is not significantly different from that predicted by the null hypothesis, but the regression line intercept reveals that the learning scores of IPA-treated bees displaying Type 1 responses are significantly lower overall than those of controls (CT). In contrast, in bees displaying Type 2 responses (Fig 4A'), the regression line intercept is higher than predicted by the null hypothesis. As low learning scores (