How to protect copycat butterflies from predators

The two species (Heliconius nima at the top and Melinaea co-mime on the bottom), both taste bad to predators, and have similar markings that send a clear message: We taste foul. (c) Mathieu Chouteau

Want to avoid being eaten? It seems that if you are a butterfly it is best to copy the markings of another species with a bad taste.

Scientists have discovered the genetic mechanism that allows butterflies to develop the same wing patterns. They observed that two species of butterflies that taste the same can form co-pairs to reinforce the message that they both taste bad.

Birds from different places prefer to avoid certain types of wings. “The butterflies mimic each other in different locations,” explained Dr Siu-Fai Lee, a member of the University of Melbourne’s Department of Genetics and Bio21 Institute.

Both species are bad-tasting and if the look alike, it reinforces the message. He said that it was in the interests of both species.

The study was published in the journal Nature and examined the Amazonian Butterfly Heliconius numata, as well as its mimicking pair.

Researchers isolated a supergene that controls mimicking. They observed different versions of the gene being switched on and off to reproduce the best wing patterns.

This mechanism is very neat, because it stops mistakes from occurring. “Those mistakes which do occur will be purged quickly and eliminated,” said Dr Lee.

People have been wondering about this for years. This is a simple solution.”