Fig. 3.

The spatial and temporal expression of trn differs in the developing claspers of D. simulans and D. mauritiana. Expression shown at 4-h intervals hAPF in Dsim w⁵⁰¹ (A) and Dmau D1 (B). (C) Illustration of the developing structures at each morphological stage (SI Appendix, Fig. S3). Black arrowheads indicate expression at the base of the developing claspers. CL, clasper; IG, internal genitalia. (D) Analysis of trn expression domain at the base of the developing clasper at stage 5. trn^sim males, Dsim w⁵⁰¹ and IL 16.30, exhibit significantly smaller expression domains than trn^mau males, IL 43 and Dmau D1 (all comparisons in trn expression domain between lines are significant [P < 0.001], except for those indicated by ns (nonsignificant), see also Dataset S5b). Boxes show the range, upper and lower quartiles, and the median for each sample. Representative trn expression at the base of the claspers is shown on the right-hand side. (E) The proportion of males with trn expression at the base of the clasper at 48 hAPF (between stages 5 and 6) in IL 16.30 and IL 43. IL43 males exhibit on average 51.9% more trn expression at the base of the claspers than IL 16.30 males (Dataset S5c).