Shape of the D. melanogaster wing was captured from 9 landmarks (A) and analyzed with TPS software . Veins are labeled both by the Comstock and Needham  nomenclature and using developmental genetic terminology (L1–L5). Individual inter-vein regions are designated by the letters A-E. (B – I): Shape differences derived from the four different datasets, namely the inbred (B, F), backcross (C, G), round robin (D, H), and Kenyan (E, I) panels. B-E shows the first principal component for landmarks of the central region of the wing (C1). The region is specified by longitudinal veins L3 and L4 and the placement of the cross veins and the margin. F-I show the shape differences for the seventh principal component for the whole wing data (W7). The whole wing and the central portion are not drawn to scale. Dark lines represent negative values, and gray positive. For whole wing PC 7 (W7) the extremes are at +/- 0.01 units and for central region PC 1 (C1) the values are +/- 0.2.