Hybrid Butterfly Found on Cold Mountaintops

NVDL: Who would think these creatures would enjoy mountaintops of all places.

clipped from news.nationalgeographic.com November 30, 2006—Some, apparently, like it cold, thanks to a rare form of genetic mixing between two butterfly species. The unnamed alpine-dwelling species of the butterfly genus Lycaeides, seen here, appears to be a genetic mashup of two known species—Lycaeides melissa and Lycaeides idas—according to a new study. "The alpine populations possess a mosaic genome derived from both L. melissa and L. idas and are differentiated from, and younger than, their putative parental species," the authors wrote in a paper published online today by the journal Science. But the new Lycaeides species is an even rarer "homoploid hybrid"—a crossbred species with the same number of chromosomes as its parents, representing a blend of the two original genomes. The discovery of the Lycaeides hybrid supports this theory, as the insect's preferred fluttering range is in the harsh cold above the treeline in North America's Sierra Nevada mountain range.