Figure 1

Heliconius butterflies sampled and sources of genetic variation in gene expression. (A) Color pattern morphs sampled for each wing. The optix gene controls two general alternative phenotypes: 1) a forewing with a red medial band and a non-red hindwing, and 2) a forewing with red base and a hindwing with red rays. Forewings were sampled in three sections as indicated and hindwings were sampled whole. Each color pattern is comprised of a mosaic of pigmented scale cells: red scales bear ommochromes, yellow scales bear 3-OH-kynurenine, and black scales bear melanin. (B) Appearance of the forewing at each of the 5 sampled developmental stages, illustrating the sequence of scale maturation and pigment deposition. (C) Array results clustered by similarity in transcription. Colored blocks represent the phenotype of each array sample, including Stage (the stage of development sampled, matching to the aligned stages in part B), Wing (hindwing: light gray; forewing: dark grey), Morph (amphitrite: red; emma: orange; favorinus: yellow; hybrid form: black; petiverana: grey), and for forewings, by Individual, highlighting the relationships among the three dissected wing sections per individual (each individual is represented by a single color, with color arbitrarily chosen). The majority of expression variation is associated with developmental stage, with further clustering by Wing, Morph, and Individual.