기후변화가 무지갯빛 나비 날개를 흐릿하게 만든다

Recent research has unveiled how climate change may dim the iridescent shine on the wings of the blue morpho butterfly. The Smithsonian Tropical Research Institute (STRI) in Panama conducted experiments revealing that exposure to high temperatures during the butterfly's pupation process causes its iridescent glow to weaken. The findings were published in a paper in the August issue of the journal "National Academy of Sciences Nexus."

Blue morpho butterflies are large insects native to tropical rainforests, known for their striking blue wings, which have become iconic symbols. So famous are these butterflies that their image has even been adopted for mobile phone emojis. To investigate the potential impact of climate change on these butterflies, researchers exposed pupating blue morpho butterflies to three temperature conditions: tropical, temperate, and high-temperature environments simulating climate change predictions.

The tropical environment served as a control group, while the temperate and high-temperature conditions were compared to IPCC's climate change projection scenarios, representing a 3.5-degree increase in global temperatures.

The researchers hypothesized that higher temperatures would affect the butterflies' unique iridescent glow. Their observations confirmed this prediction. Butterflies raised in high-temperature environments had duller wings with altered colors and delayed development compared to their counterparts in lower temperature conditions.

Warmer temperatures did not significantly impact butterflies raised in cooler environments. The researchers attribute the change in the butterflies' wing glow to alterations in the nanostructures on the wing scales. These nanostructures reflect and refract light to create the distinctive blue iridescence. When the nanostructures become closer together due to higher temperatures, the overall width of the wing scales decreases, altering the butterfly's iridescent appearance.

However, the long-term implications of these changes on predators or potential mates remain unclear. Despite the butterflies' iridescent wings disorienting predators, the researchers suggest that a less vibrant or altered coloration may reduce the butterflies' ability to avoid predation.