Recently, scientists have been baffled when they discovered that some tropical butterflies are living longer than their relatives. The butterflies that have stumped researchers belong to the Heliconius genus and inhabit the tropical rainforests of South and Central America, and have lifespans that wildly vary.
Lifespans of Butterflies
For example, the Dione juno butterfly lives for two weeks after reaching adulthood, while the Heliconius hewitsoni lives for 348 days (over 49 weeks); almost 25 times longer. Furthermore, there are other species in the Heliconius genus that also have lengthy lives, lasting between 106 to 277 days, according to a study published in the journal Nature Communications on June 22, 2026.
Some researchers believe that Heliconius’ extended lifespan is caused by the insects eating a more enhanced diet instead of relying on carbohydrates like other butterflies. However, the exact reason why these butterflies are living longer is a mystery, which is what inspired Dr. Jessica Foley, the study’s lead author and a postdoctoral scholar at Tufts University’s Jean Mayer USDA Human Nutrition Research Center on Aging in Boston, to take an in-depth look at the intriguing butterfly genus.
Vast Differences
In an email to KSL, Foley wrote, “We see vast differences in lifespan across the animal kingdom — adult mayflies famously live only for a day, whereas some whales and sharks can live for hundreds of years. I’m interested in the evolutionary basis of these kinds of lifespan differences because they might hold insights relevant for healthy aging in humans.”
Additionally, with the help of her colleagues, Foley found that while nutrition has its part to play, some Heliconius have also evolved an anti-aging mechanism the researchers are still unraveling. With that, they are figuring out how it works for the butterflies and how it could be a model for understanding human longevity.
Butterflies Diet
The study’s authors wanted to find out if removing the unusual food source from the butterflies’ diet would end up shortening their lifespan, Foley stated. Normally, adult butterflies feed exclusively on flower nectar, fueled only by carbohydrates rather than the amino acids and lipids, which are used for egg and sperm needed to reproduce, they received from plant material as caterpillars before metamorphosing.
While talking about the lipids and amino acids, Foley stated, “The general evolutionary strategy is to reproduce as much as they can until those resources are spent, which doesn’t take very long for these small insects. They usually die soon after this finite resource is used up.”
However, scientists have found that most Heliconius species have adapted their diets to include pollen, even as adults, which could contribute to the butterflies’ lifespan longevity. For this reason, the researchers studied the relationship between the pollen and Heliconius to see what health benefits are gained by the butterflies.
Understanding
Foley stated that she wanted to have an understanding of “the real extent of this lifespan extension in Heliconius, to understand whether it was also accompanied by slowed physiological aging, and to figure out whether they would still show a lifespan extension — indicating evolved mechanisms of longevity — even without the pollen.”
The scientists studied 28 Heliconius species, of which only six were non-pollen-feeding, and they had a lifespan of between 14 to 98 days. However, the team found that even without the pollen, the Heliconius butterflies were still living much longer than their non-pollen-eating relatives.
Testing
To help them factor in age-related decline in older butterflies, the researchers used a unique device to measure the creatures’ grip strength. They called the device they built “The Pullinator,” a perch lined with sandpaper attached to a lightweight wooden base.
“We placed this on a lab balance, zeroed the balance, and then gently held a butterfly by the wings and lowered it until it grasped the perch,” Foley described. “We then tugged until it let go — but as the butterfly tugged, the balance would drop negative, and we could use the maximum negative reading as an indication of how much weight the butterfly could carry before it let go.”
One of the species tested on The Pullinator was the Heliconius hecale butterfly, which can live up to 277 days. This butterfly displayed little to no physiological decline during the grip-strength test. At the same time, the closely related Dryas iulia, which doesn’t feed on pollen and lives for 98 days, showed signs of age-related decline. Furthermore, the Heliconius hecale was also able to maintain its body mass and muscle function for longer, even when it was deprived of pollen.
Hopeful
Scientists are hopeful that if they gain an understanding of how the Heliconius butterflies are able to live longer, they may be able to use that concept to help create other anti-aging techniques to help people. For example, Foley’s team is interested in investigating the more mysterious longevity mechanisms of Heliconius, as well as the butterflies’ robust cognition — they have large brains and impressive long-term memory, even as they age.
An expert not involved in the study added their insight into why the research that Foley and her team are doing is important. The new research shows that Heliconius can be a potential model insect group for studying increased longevity, including adaptations that could slow aging and have potential applicability to humans, said Dr. Jaret C. Daniels, curator and interim associate director for the McGuire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History.
“This study reinforces the utility of many insect groups and important model organisms for various fields of research,” Daniels said in an email to KSL. “Since many insects are often overlooked or underappreciated/undervalued by humans, studies like this can help change that perspective.”
Sources:
KSL: An unusual strategy helps some tropical butterflies live 25 times longer than their relatives
Nature Communications: Evolution of increased longevity and slowed ageing in a genus of tropical butterfly
Image by Green lama Courtesy of Wikimedia – Creative Commons
