Selection drives divergence of eye morphology in sympatric Heliconius butterflies

When populations experience different sensory conditions, natural selection may favor sensory system divergence, affecting peripheral structures and/or downstream neural pathways. We characterized the outer eye morphology of sympatric Heliconius species from different forest types and their first-generation reciprocal hybrids to test for adaptive visual system divergence and hybrid disruption. In Panama, Heliconius cydno occurs in closed forests, whereas Heliconius melpomene resides at the forest edge. Among wild individuals, H. cydno has larger eyes than H. melpomene, and there are heritable, habitat-associated differences in the visual brain structures that exceed neutral divergence expectations. Notably, hybrids have intermediate neural phenotypes, suggesting disruption. To test for similar effects in the visual periphery, we reared both species and their hybrids in common garden conditions. We confirm that H. cydno has larger eyes and provide new evidence that this is driven by sele..., Butterfly specimens
We collated samples from outbred stocks of Heliconius cydno chioneus (C) and Heliconius melpomene rosina (M), established from wild butterflies caught in Gamboa and the nearby Soberanía National Park, Panama. Most butterflies were sampled in 2015-2017 (9 H. cydno and 20 H. melpomene) or 2018-2019 (16 H. cydno and 10 H. melpomene) versus fewer samples in 2008-2009 (9 H. cydno and 3 H. melpomene). We also exploited previously sampled reciprocal F1 hybrids between H. cydno and H. melpomene, generated by crossing a H. cydno female with a H. melpomene male (CxM) or a H. melpomene female with a H. cydno male (MxC). All hybrids were generated in 2017-2019, involving four CxM crosses and six MxC crosses (unique parents for each cross; see Table S1, Fig. S2). All butterflies were reared under common garden conditions in the Smithsonian Tropical Research Institute insectaries in Gamboa, and all specimens were preserved in DMSO/EDTA/NaCl and stored at -80° C as described in Mer..., , # GENERAL INFORMATION

1\. Title of Dataset: Selection drives divergence of eye morphology in sympatric *Heliconius* butterflies

2\. Author Information:

1. Daniel Shane Wright (Division of Evolutionary Biology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany)
2. Juliana Rodriguez-Fuentes (Division of Evolutionary Biology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany)
3. Lisa Ammer (Division of Evolutionary Biology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany)
4. Kathy Darragh (Department of Zoology, University of Cambridge, Cambridge, United Kingdom; Smithsonian Tropical Research Institute, Panama)
5. Chi-Yun Kuo (Division of Evolutionary Biology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany)
6. W. Owen McMillan (Smithsonian Tropical Research Institute, Panama)
7. Chris D. Jiggins (Department of Zoology, University of Cambridge, Cambridge, United Kingdom; Smithsonian Tropical Research Institute, Panama)
8. Stephen H...