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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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Balanced polymorphisms and their divergence in a Heliconius butterfly
Abstract The evolution of mimicry in similarly defended prey is well described by the Müllerian mimicry theory, which predicts the convergence of warning patterns in order to gain the most protection from predators. However, despite this prediction, we can find great diversity of color patterns among Müllerian mimics such asHeliconiusbutterflies in the neotropics. Furthermore, some species have evolved the ability to maintain multiple distinct warning patterns in single populations, a phenomenon known as polymorphic mimicry. The adaptive benefit of these polymorphisms is questionable since variation from the most common warning patterns is expected to be disadvantageous as novel signals are punished by predators naive to them. In this study, we use artificial butterfly models throughout Central and South America to characterize the selective pressures maintaining polymorphic mimicry inHeliconius doris. Our results highlight the complexity of positive frequency‐dependent selection, the principal selective pressure driving convergence among Müllerian mimics, and its impacts on interspecific variation of mimetic warning coloration. We further show how this selection regime can both limit and facilitate the diversification of mimetic traits.
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- Award ID(s):
- 1736026
- PAR ID:
- 10366411
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 11
- Issue:
- 24
- ISSN:
- 2045-7758
- Format(s):
- Medium: X Size: p. 18319-18330
- Size(s):
- p. 18319-18330
- Sponsoring Org:
- National Science Foundation
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