There are more than 160,000 moth species on Earth, and they are best known for being nocturnal flyers and pollinators. Now, some moths are opening an evolutionary window into how one species can diverge into separate species with different characteristics. Disco Genes may be behind the dramatic differences in the flight patterns of two colorful moths. The study was published in the journal Nature on August 27th. Proceedings of the Royal Society B: Biological Sciences And we detail how this gene helps control day and night flight.
When species diverge
In nature, a species can branch out over time into two or more species. This process Speciation It occurs when individuals from a single population become geographically isolated. The Galapagos finches Charles Darwin is is one of the most famous examples of speciation. 13 finch species diverged from a single ancestor A time when populations of organisms were dispersed across multiple islands and evolved separately. If populations of organisms continue to exist separately for a long period of time, they will eventually Loss of mating ability.
for Some mothsTheir genes are influenced by the time of day they are most active, rather than separation by physical barriers like oceans or mountain ranges. New ResearchThe team focused on two closely related moth species that have overlapping ranges in the southeastern United States.
[Related: Moths fight against echolocating bats with sounds of their own.]
Rosy Maple Moth teeth Genus Dry OcampaThey have a thick, fluffy mane with candy-colored pink and yellow scales on their heads and abdomens. Male and female rose-colored moths fly only at night.
Pink-striped Oakworm Moth It’s not flashy, but it’s a little on the subdued side. Genus AnisotaThey have more earthy color tones, such as mustard yellow, dark brown, and gray. Female pink-striped oakworm moths are active from dusk to early evening, while males prefer to fly during the day.
“These two [species] They’re very similar,” said study co-author Yash Sondhi, an entomologist at the Florida Museum of Natural History. It said in a statement“They have differentiated along one axis: flight.”
In previous studies, Dry Ocampa and Anisota Emerged from a single species approximately 3.8 million years agoBy evolutionary standards, this is fairly recent, and there are still some important differences and similarities between them. Some species in this genus Anisota All are diurnal, but unlike the modern female pink-striped oakworm moth, which prefers twilight and nighttime flying, the nocturnal rose-colored maple moth is also the only known species in the genus. Dry Ocampa.
Initially, Sondhi thought that both types of moths would provide a good opportunity to study how insect vision evolves and when species change their activity patterns. But that didn’t happen.
“I went looking for differences in color vision. Instead I found differences in clock genes. In hindsight, it makes sense,” Sondhi said.
The gene that “tells time”
Clock genes are specialized genes that control circadian rhythms in both animals and plants. Changes in the proteins produced by clock genes cause cells to become active or dormant on an approximately 24-hour cycle. Clock genes are: Sleep-wake cycleClock genes are biological Cell growth, blood pressure, Body temperatureand metabolism It is found in a wide range of organisms.
“This is a system that’s in every organism, from fruit flies to mammals to plants,” says Sondhi. “They all have some kind of timekeeping mechanism.”
[Related: The science behind our circadian rhythms, and why time changes mess them up.]
After finding these Differences in clock genesSondi is Transcriptome The transcriptomes of the two moth species contain only one subset of genetic material, When and where genes are turned on or off It is present in the cells and tissues of living organisms. The genome contains all of an animal’s DNA.The transcriptome has more specific information about these proteins and is therefore useful for examining differences in protein levels in an organism throughout the day.
Sondhi found several genes that are expressed in different amounts in both species of moths. I put more energy into my sense of smell.Meanwhile, day-flying siskins produced more genes related to vision.
of Disco Genes and their “zinc fingers”
Another gene emerged during this analysis.Disco. Abbreviation Disconnected, Disco It was expressed at different levels during the day and night in both species. Fruit fly research Found Disco We can indirectly affect circadian rhythms through the production of neurons that send clock enzymes from the brain to the body.
of Disco Genes found in moth samples It was about twice the size of a fruit fly. Extra zinc fingers. these are Active part of the gene It directly interacts with proteins, DNA, and RNA. Disco This gene is at least partly responsible for the shift in the rose maple moth to nocturnal flying.
[Related: Why artificial light—and evolution—trap moths.]
he, Disco The rosy maple moth gene Disco Sondi discovered the oakworm’s genes. The 23 mutations that separated themThese mutations were also located in active parts of the gene, and so may also contribute to some of the moths’ visible physical differences.
Further research could also help scientists understand how genes change in the wild and how speciation occurs at a molecular level.
