Fig. 3.

Mechanisms of royalty biasing. (a) Proposed mechanisms of caste determination. Larvae of normal genotypes receiving 1 arbitrary unit of the caste-determining environmental cue (e.g., food) switch from the small worker (SW) to large worker (LW) developmental path (dashed line), whereas larvae receiving 2 units switch from the worker to queen developmental path (solid line). Royal–LW patrilines have lower thresholds for both switches. Royal–SW patrilines have a lower threshold only for the queen–worker switch. (b) Mean ± SEM proportion of individuals sampled that were SW, LW, and queens for the four royal–LW patrilines, the six royal-SW patrilines, and the 19 normal unbiased patrilines.