Butterflies Have Different Visual Characteristics Depending on Sex

[Fam Times reporter Joo-hye Park] Biologists at the University of California in Irvine, United States, have discovered that butterflies of a particular species have different eyes depending on their sex.

Because of sex-related evolutionary traits, female and male butterflies receive different visual information.

The study was published in the journal Molecular Biology and Evolution and made an important contribution to evolutionary biology.

This is because it revealed the new finding that butterflies’ eyes vary in response to selective environmental factors.

Adriana Briscoe, a professor of ecology and evolutionary biology at the University of California’s Ayala School of Biological Sciences, analyzed the structural components of butterfly eyes and the genes controlling color-detecting photoreceptors.

According to the study, a species called the red postman butterfly (Heliconius erato) has unique visual photoreceptors that differ by sex.

In other words, the eyes of females and males are markedly different.

Females have two types of ultraviolet opsin genes.

They are UVRh1 and UVRh2.

Males do not have UVRh1.

The researchers were shocked by this groundbreaking finding.

In the butterfly world, the red postman is the first—and so far the only—organism known to have eyes determined by sex.

Briscoe said, “It has been demonstrated that male and female red postman butterflies see the world through different eyes.”

Briscoe explained, “Depending on the color preferences of pollinators—butterflies in this case—this could have a major influence on the evolution of the colors of the flowers they visit.”

Briscoe added, “Flowers can continue evolving to take on colors that butterflies can see. The butterflies’ sex has now become a factor in these interactions.”

Reporter Joo-hye Park, fam1@pcss.co.kr