An international team led by investigators at the City University of New York examine butterfly evolution in North America and Central America in a paper appearing Monday in Nature Ecology & Evolution. Based on targeted sequencing data spanning 391 genes in 2,244 butterfly species sampled in 118 countries or specimen collections, the researchers put together a phylogeny that places butterfly origins at roughly 100 million years ago. In the process, the researchers also call for the reclassification of three dozen butterfly tribes and link butterfly origins to legume-feeding insects in the Americas. "Our data support the hypothesis that butterflies originated in the Americas in the late Cretaceous, 100 million years after the origin of angiosperms, and that they first fed on legumes," the authors report, noting that "molecular, host plant, and geographic data provided here serve as a baseline for future comparative analyses of butterflies."