A Comprehensive and Dated Phylogenomic Analysis of Butterflies

Area of Science:

• Evolutionary Biology
• Phylogenetics
• Insect Ecology

Background:

• Butterflies (Papilionoidea) are ecologically significant with over 18,000 species.
• They are crucial models for studying speciation, ecology, biogeography, and climate change.
• A comprehensive phylogenetic framework for butterflies has been lacking.

Purpose of the Study:

• To construct a robust, dated higher-level phylogeny for butterflies.
• To provide a backbone for a revised butterfly classification.
• To enable future comparative studies on butterfly evolution and ecology.

Main Methods:

• Phylogenomic analysis of 352 loci (>150,000 bp) from 207 species.
• Utilized a new anchored hybrid enrichment (AHE) gene kit (BUTTERFLY1.0).
• Achieved a 35-fold increase in gene sampling and 3-fold increase in taxon sampling compared to previous studies.

Main Results:

• Butterflies originated ~119 million years ago; most extant lineages diverged post-K-Pg extinction.
• Papilionidae are sister to all other butterflies; Hesperiidae + Hedylidae are sister to the rest, indicating a reversal to nocturnality.
• Pieridae are sister to Nymphalidae; Lycaenidae and Riodinidae are closely related.
• Ant association evolved independently multiple times in Lycaenidae and Riodinidae.

Conclusions:

• This study overturns previous understandings of butterfly evolutionary history.
• Many traditional butterfly subfamilies and tribes are found to be polyphyletic.
• The new phylogeny offers a foundational framework for butterfly systematics and future research.