The butterflies that languish lazily through the forests and jungles of the Americas hold many secrets. His more than 30 species in this group include many mimetic animals. The longwing wing markings of several distantly related species are so similar that one Victorian naturalist theorized that harmless species may exist. imitate deadly things to avoid predators.
In the age of genome sequencing, biologists have discovered another oddity in the Nagavage.in paper published last week In the Proceedings of the National Academy of Sciences, researchers report the long wings of female zebras. Thanks to genes on the sex chromosomes, we can see colors that men cannot see. Understanding how it got there may shed light on how gender differences can evolve.
Like primates, butterflies have a small number of proteins that are sensitive to specific wavelengths of light that work together to produce their ability to discriminate colors. Adriana Briscoe, a professor at the University of California, Irvine, and author of a new paper, is intrigued by the vision of zebra longwings and asks students to examine the species’ genome for well-known color vision genes. I asked you to This gene, known as UVRh1, encodes a protein that is sensitive to UV light. To my surprise, it was nowhere to be found.
Dr. Briscoe and colleagues investigated further and utilized genomic data from additional zebra macroptera and found that UVRh1 was present, but only in females. Laboratory experiments have confirmed that females can see markings that are invisible to males. They eventually located the gene in an unexpected location: on the butterfly’s small sex chromosome.
Butterflies’ sex chromosomes are unstable, often dropping out or completely missing genes that are picked up by other chromosomes, Dr. Briscoe said. This makes it a somewhat unusual place to store something as important as the genes for color vision.
Also, some butterflies are known to have different color vision between males and females. It probably has something to do with females finding males to mate with.. In these species, seeing some colors is a waste of resources for males. For these insects, however, the difference in vision seems to be related to how the genes are regulated rather than their placement on the sex chromosomes. Somehow, with Zebra Longwing, it went a different direction.
How did UVRh1 get to where it is today? Did it start on the sex chromosome? Or did it move there from the shared chromosome of the zebra longwing and then somehow be edited out of the males? For men, maintaining more complex color vision can be more difficult than it’s worth.
Researchers suggest that the question of what happened in a zebra’s long wing and when it happened has deeper implications than simply understanding what butterflies look like. . It touches on the mysteries of evolutionary biology. The most successful females and most successful males within a species can have very different or even contradictory traits. What kind of genetic mischief is required to produce this split?
If UVRh1 is derived from the sex chromosome, the researchers write, it would be a good way to avoid situations where traits that are optimal for females would interfere with other sexes.
If so, “it suggests that UV color vision has already started being restricted to women, ignoring the possibility that it might even be a burden for men,” said a professor at the University of California, Irvine, US. JJ Emerson, an academic, said. Author of a new paper. “If UVRh1 is harmful to men, this jump would be a neat trick.”
Further research should allow us to speculate about what happened with the zebra’s longwing, Dr. Briscoe said. There are several long-winged species whose genomes have not yet been fully studied. In particular, the Aede longwing, which lives in the Amazon Basin’s remote forests, promises potential answers.
If some women see more than men, it suggests that UVRh1 actually started on the sex chromosome, Dr. Briscoe said.
This will be another data point in a growing body of research examining the differences between male and female butterflies.
“Back in the day, nobody studied the differences between male and female butterflies,” says Dr. Briscoe. “There was absolutely no attempt to figure out if they were doing anything different.”
She suspects evolution may have brought other interesting differences to macropters, which scientists are beginning to uncover.