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Abstract The evolutionary origins of mimicry in the Easter egg weevil, Pachyrhynchus, have fascinated researchers since first noted more than a century ago by Alfred Russel Wallace. Müllerian mimicry, or mimicry in which 2 or more distasteful species look similar, is widespread throughout the animal kingdom. Given the varied but discrete color patterns in Pachyrhynchus, this genus presents one of the best opportunities to study the evolution of both perfect and imperfect mimicry. We analyzed more than 10,000 UCE loci using a novel partitioning strategy to resolve the relationships of closely related species in the genus. Our results indicate that many of the mimetic color patterns observed in sympatric species are due to convergent evolution. We suggest that this convergence is driven by positive frequency-dependent selection. [Biogeography, discrete traits, frequency-dependent selection, mimicry, partitioning, Philippines, polymorphic, UCE.]
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Pachyrhynchus Weevils Use 3D Photonic Crystals with Varying Degrees of Order to Create Diverse and Brilliant Displays
Abstract The brilliant appearance of Easter Egg weevils, genusPachyrhynchus(Coleoptera, Curculionidae), originates from complex dielectric nanostructures within their elytral scales and elytra. Previous work, investigating singular members of thePachyrhynchusshowed the presence of either quasi‐ordered or ordered 3D photonic crystals based on the single diamond () symmetry in their scales. However, little is known about the diversity of the structural coloration mechanisms within the family. Here, the optical properties withinPachyrhynchusare investigated by systematically identifying their spectral and structural characteristics. Four principal traits that vary their appearance are identified and the evolutionary history of these traits to identify ecological trends are reconstructed. The results indicate that the coloration mechanisms across the Easter Egg weevils are diverse and highly plastic across closely related species with features appearing at multiple independent times across their phylogeny. This work lays a foundation for a better understanding of the various forms of quasi‐ordered and ordered diamond photonic crystal within arthropods.
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- Award ID(s):
- 1856402
- PAR ID:
- 10375149
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 18
- Issue:
- 20
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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