An ingredient produced by male butterflies, Heliconius Melpomene, acts as a sexual inhibitor.

However, when produced by certain plants, it attracts these same insects.

In the report published in Le Monde newspaper, writer Nathaniel Herzberg says that for a long time, this strange butterfly was famous for its ability to produce bitter and toxic substances that succeeded in keeping predators away from it.

Chemical Chastity Belt

Heliconius Erato and Heliconius Melpomene share the same colored signal on their wings to increase alertness, a behavior biologists call "Mueller simulation."

Thus, they share the characteristics of taste and appearance.

In a study published in the journal PLoS Biology on January 19, an Anglo-American team added to these two properties of smell.

After chemical and genetic analysis, researchers recently showed how these males can produce an unpleasant substance called pheromone (excreted outside the body by animals and if it reaches another individual of the same species, it makes him respond to these chemical signals in some way) with the aim of keeping (of his kind) organisms away and not other organisms Threatening her.

But during sexual intercourse, they leave this substance inside the female reproductive system, which is a kind of so-called chemical chastity belt that increases the chances of childbearing.

In a thesis she presented at the University of Cambridge during this study and the university published a press release about it, Kathleen Darag, now a researcher at the University of California, wanted to uncover the rest of this mystery, which is the origin of the phenomenon.

Other researchers have already demonstrated the use of Heliconius melbuminine for osimine, a terpenoid hydrocarbon that is naturally produced by plants.

But they believed that the insect only searches for this substance in plants when searching for food.

This strange butterfly was known for its ability to produce toxic substances to keep predators away (Richard Barts - Wikipedia)

Attract and alienate

The writer states that the scholars have shown that this is not the case.

Not only do butterflies produce osmine on their own, they do so through a different mechanism.

"We have discovered a new gene that is not present in plants that produces osimin. Accordingly, the production of this pheromone evolved independently and by different methods in plants and butterflies," Darag explains.

This has impressed those interested in the field of evolution, who have always yearned to understand the paths of evolution and development of certain traits.

"The ability to show that plants and animals share a common chemical language, and that they each find an evolutionary advantage in it, is amazing," says Adriana Brisco, a specialist in butterfly evolution at the University of California.

But behavioral biologists wonder: How can the same chemical compound attract butterflies when it emerges from a plant, and repel them when excreted by other butterflies?

"This is what we don't understand very well," Darraj admits.

The reproductive advantage that males can find in this matter is clear for their peers who secrete a sex suppressant in the female and secure their offspring, and for females who also receive this substance.

The researcher adds, "Grooming a fully fertilized female is a waste of time and energy, especially since she will not accept this immediately after the first mating."

The same chemical compound attracts butterflies when it emerges from a plant and repels them when other butterflies excrete it (Wikipedia)

A little peace for females

"Females are often bullied by males, so if this gives them a little peace, they benefit from it as well," says Chris Jiggins, a professor at Cambridge University who led this research.

Note that they have the ability to store their first partner's semen and use it multiple times.

All this does not explain the distinction that this insect makes between negative and positive uses of this substance.

"Certainly, it is the context that allows the butterfly to interpret the same scent differently," Darag says.

For this reason, researchers will try to better define the two behaviors and look for this pheromone in other species of butterflies.