Diverse Crystals Account for Beetle Sheen

Not only are beetles among the most diverse group of animals on Earth, but some rival the most flamboyant birds and dazzling coral reef fish with their metallic sheens. Researchers have now traced the evolutionary history of this iridescence in one group of beetles, the weevils, and identified an unexpectedly varied assortment of complex light-altering crystals in the insects. The new work also shows that these diverse crystal architectures all share a single origin in these beetles' evolutionary past. Weevils "have developed high crystal diversity from a relatively modest tool kit," says Ainsley Seago, a systematist with the Australian National Insect Collection in Canberra, who led the work.