Ateam of researchers led by evolutionary biologist Nick Grishin at the University of Texas Southwestern Medical Center in Dallas has sequenced the genomes of all butterfly species in the US and Canada, according to a preprint published November 4 on bioRxiv.
Grishin’s team collected butterflies in the wild and also worked with museums and butterfly enthusiasts to obtain genetic material from all 845 butterfly species north of Mexico. Once the researchers had sequenced each genome, they constructed an evolutionary tree based on differences in protein-coding genes. The tree was largely in agreement with previous evolutionary groupings, but the team suggested reclassifying 40 butterfly species at the genus level, reports Nature.
They also found that some groups of butterfly species that evolved faster than others may have done so through interactions with other species that helped the butterflies thrive. For example, Polyommatinae, a group of blue butterflies, has a symbiotic relationship with ants, while Pierini, white butterflies, can eat plants that are toxic to other insects. Both of these were among the fastest-evolving butterfly groups.
Most of the new genomes are “draft” genomes that use short DNA sequences. These genomes can be used to infer evolutionary relationships, but they don’t provide enough information for specific studies of individual genes. The team did create more detailed reference genomes, gene databases derived from multiple organisms, for 23 of the species.
Some researchers are calling the study “a landmark in genomics” due to its scope, according to Nature. “It’s a beautiful piece of work, a tour de force, to do all that,” James Mallet, an evolutionary biologist at Harvard University who was not involved with the study, tells Nature.
Emily Makowski is an intern at The Scientist. Email her at email@example.com.