UV vision: Female red postman butterflies see two colours of UV

By Madeline Bodin

Female red postman butterflies see an extra colour in the ultraviolet part of the light spectrum that even the males of their species cannot.

While many animal species can see one colour of UV, the ability to see multiple colours in the UV spectrum is rare. Mantis shrimp and hummingbird hawkmoths may also see multiple colours of UV, according to Susan Finkbeiner at California State University, Long Beach and Adriana Briscoe at the University of California, Irvine.

Finkbeiner trained 80 Heliconius erato, a Central American butterfly species, and 120 of two other butterfly species to sip from a feeder …