Fig. 5

The mushroom body- the centre for learning and memory - shows increased size and neuron number in E. dilemma females. (A) Single micro-CT slice showing the regions of the mushroom body. The calyx (Ca) is the input region (light pink box) with three subcompartments that receive sensory-specific information. The lip (lp) for olfactory input (dark red), the collar (Co) for visual input (pink), the basal ring for multisensory information. The intrinsic neurons- Kenyon cells (KC) -(white) reside in and around the calyx. The pedunculus and lobes are the sensu-lato output region (red) (B) With a shared negative allometry females show an upshift in the overall size of the mushroom body compared to males (see supplementary Table S3). (C) The expansion of the calyx in females is driven primarily by an upshift in the lip. (D) Total volume of the Kenyon cell cluster as a proxy of neuron number, showing a larger cluster in females. (E) Interpolated surface area of the calyx with increased surface on females. (F) 3D average reconstruction of the mushroom body in female and male E. dilemma (red) and associated cluster of Kenyon cells (transparent white-black dotted), showing the association between surface area and volume of neuron cluster.