The enigmatic butterflies of the genus Heliconius have fascinated science for centuries and, now, a group of researchers has just discovered one of their secrets: Its exceptional longevity is due to an evolutionary adaptation to take advantage of the nutrients in pollen.
The magazine Nature Communications collected this Tuesday a study that explains how this colorful genus of butterflies has evolved to have an unusually long life: some specimens they live almost a yearquite a milestone considering that the average life expectancy of these insects is six weeks.
This finding classifies Heliconius as the longest-lived butterflies recorded to date. In addition, scientists believe that they may constitute a new model to study prolonged longevity.
To reach this conclusion, the researchers (from centers in the United Kingdom, the United States and Panama) have combined data from butterfly farms, mark-release-recapture studies, and controlled experiments in insectaries to compare lifespan and aging across the Heliconius genus.
This has allowed them to verify that, even in the wildHeliconius have one of the longest adult lifespans documented in butterflies: it has been observed that some individuals they live at least six months in freedomcompared to six weeks for their closest relatives.
The secret of longevity
But what is the reason for this unique longevity? Researchers link it to its innovative ability to feed on pollen when they reach adulthoodwhich gives them essential lipids and amino acids to delay physical deterioration.
The lipids and amino acids in pollen provide butterflies with a greater energy and immune budget, which makes them less vulnerable to external threats and increases your life expectancy.
On a physical level, butterflies that consume pollen lose less body mass as they age and maintain greater muscle strength compared to those who do not take it.
The authors have studied the effect of diet on longevity using a representative pollen-feeding species (Heliconius hecale) and a non-pollen-feeding species (Dryas iulia).
In the Heliconius hecale species, butterflies fed with pollen achieved an average survival of 63 days, compared to 47 days for those that did not take pollen.
An advantageous adaptation
Furthermore, Heliconius hecale retains a general longevity advantage over Dryas iulia even without access to pollen in the diet: it manages to live an average of 47 days compared to 29 days for Dryas iulia. This would indicate that, in addition to the nutritional contributions of pollen, the species has had an evolutionary adaptation that allows you to live longer.
«The longevity provided by pollen requires an adapted biology to take advantage of it. Heliconius has not only adopted the habit of eating pollen, but has also evolved unique physiological adaptations to fully absorb and exploit its nutritional benefits to extend its life,» the authors point out.
Researchers have seen that within the heliconia genus there are large variations in life expectancy, ranging from 14 days for Dione juno and 348 days for Heliconius hewitsoni (one of the longest-lived butterflies recorded), with an average longevity of 177 days.
After Heliconius hewitsoni, the longest-lived butterflies in the genus are Heliconius erato, which usually live 271 days, Heliconius ismenius (242 days), Heliconius cydno (227 days), Heliconius atthis (210 days), Heliconius numata (210 days), Heliconius hortense (198 days) and Heliconius charithonia (184 days).
EFE Agency.
GML
