Butterflies mimic each other’s flight pattern to warn off predators

By Imogen Howse via SWNS

Butterflies mimic each other’s flight patterns to warn off predators, reveals new research.

Scientists have long known that many inedible species of butterfly have evolved near identical color patterns which act as warning signals to predators.

Essentially, a predator eats one butterfly, discovers that it is inedible, and henceforth avoids all butterflies that look similar – meaning the butterflies are protected.

However, a new study has revealed that these butterflies have also evolved similar flight behaviors, a technique that serves to protect them in the same way.

This time, predators will avoid all butterflies who appear to fly alike, widening the pool of butterflies that are protected from harm.

Researchers from the University of York in the UK used high-speed video footage to record the flight of 351 butterflies – belonging to 38 species and 10 distinct color pattern groups – in South America.

The team investigated what affected a butterfly’s flight behavior the most, considering factors such as wing beat frequency, wing shape, habitat, temperature, and color pattern mimicry groups.

Results, published in the journal Proceedings of the National Academy of Sciences, showed that the color pattern mimicry group a butterfly belonged to was the most important determinant of flight behavior.

Lead author Edd Page, a Ph.D. student at the University of York, said: “From an evolutionary perspective, it makes sense to share the color pattern between species to reduce the individual cost of educating predators to the fact that they don’t taste nice.

“Once a predator has tasted one, the visual clues on others indicate that they too are also inedible.

“We wanted to see whether the same case flight corresponded to color - could predators be driving the mimicry of flight as well as color patterns?

“We found that distantly related butterflies belonging to the same color pattern mimicry group have more similar flight behavior than closely related species that display different warning coloration.

“So, to a predator, the butterflies would not only look the same through their color patterns but would also look the same through the way they move.

“Sharing flight behavior across multiple species seems to reinforce this ‘don’t eat me’ message.”

The research team from the University of York looked specifically at a tribe of butterflies called the Heliconiini, which have around 100 species and subspecies distributed around the Neotropics.

Each species and subspecies belonged to one of several distinct color pattern mimicry groups.

They also investigated a few species from the ithomiine butterfly tribe, which, despite splitting from the Heliconiini about 70 million years ago, have very similar ‘Tiger’ color patterns.

Page said: “It is fascinating that this behavior has evolved between distant relatives over a long period of time.

“But we can also see flight behavior diverging between differently patterned populations within a species over a relatively short period of time too.”

Professor Kanchon Dasmahapatra, who oversaw the study, added: “The extent of flight mimicry in this group of butterflies is amazing.

“It is a great example of how evolution shapes behavior, with selection from predators driving subtle changes which enhance the survival of individuals.”

He said that the next step would be to identify which genes cause these changes, which will reveal how this behavioral mimicry evolves.