Drosophila melanogaster The common fruit fly, is a foundation stone for genetics and biology labs. Honor of Marcus Stensmyr hide…
Courtesy of Marcus Stensmyr
Next time you turn a fruit fly in your kitchen, take the heart off the fact that people have apparently fought with these infections for about 10,000 years.
A study published Thursday suggests Drosophila melanogaster ] first shook up with humans when the insects flew into the elaborately painted caves of ancient people living in southern Africa.
According to a report published Thursday in the journal Current Biology .
Researchers say the flies would have followed the enticing smell of stored marulamese collected and stored by cave houses in Africa. This delicious yellow fruit was a staple in the region these days – and it was also the fruit that wild flies apparently developed to be addicted to in nearby forests.
The humble fruit fly now lives with people worldwide and is one of the world’s most studied creatures. For more than a century, biological and medical laboratories have been addicted to this flight – a scientist notes that at least nine times the Nobel Prize in Physiology or Medicine has been awarded research on Drosophila . One of these prizes was won by Thomas Hunt Morgan of Columbia University, whose aviation research in the early 1900s picked this species from obscenity and turned it into a foundation stone for genetics.
“It’s small, it’s cheap to raise, it’s interesting genetics,” explains Thomas Kaufman, biologist at Indiana University in Bloomington. “We think the flies are quite charismatic, they are wonderful, they are beautiful little animals and we love them. Seriously.”
But despite all the love and study, the origins of origin and how it first
“I’ve been thinking about this in the past 20 years,” says Marcus Stensmyr, biologist at Lund University in Sweden using these flies to study the olfactory system. “It has really been a lifelong ambition if you want to find where they are from.”
Researchers have known for decades that the airplanes like humans seem to have begun in Africa – somewhere. 19659008] “You’ll find them in your kitchen. You find them in my kitchen – you find them in everyone’s kitchen, “says Stensmyr.” But if you go out into the woods, you simply do not find them. “
Recently, researchers gathered flies from all over Africa and looked at their genes They found that the largest genetic diversity was found in flies from Zambia and Zimbabwe, suggesting that this species began in the southern central region of the continent.
But travel to that region failed to pop up much of everything. 19659008 ] “After a number of failed excursions down to Africa, Stensmyr says,” We thought, “OK, maybe they’re associated with some fruit in their original home.” “
Stensmyr and his colleagues studied a long list of possible fruits , looking for all the features that D. melanogaster are known to be preferred. The flies favor citrus fruits – for example oranges.
Courtesy of Marcus Stensmyr
“We came to a candidate fruit – it was marula fruit,” says Stensmyr. The yellow fruit is about the size of a large plum, with a hard stone in the middle. “It has a sweet and nice taste.”
The researchers traveled to the woodlands of the Matobo National Park in Zimbabwe. They found fruiting marula trees and put out traps. Bingo – they caught D. Melanogaster .
“We found lots of flies,” says Stensmyr.
Further study showed that wild D. melanogaster strongly prefer marula fruit over oranges.
What’s more, it’s also a fly commonly used in laboratories. This tribe was formed in 1916 from an airline in Canton, Ohio.
“They have actually maintained the preference for marula,” says Stensmyr. “They would also go to Marula.”
The researchers isolated a certain chemical in this fruit – ethylisovalized – which seemed particularly important. Fluorescence between marula and oranges spiked with this chemical failed to pick each other, indicating that the two choices seemed the same as the flies.
All this provides an exciting clue for how these insects may have started to make their homes with people. Nearly where the researchers found the wild flies there are caves where the Sanctuaries once lived. These people left for beautiful cave paintings – like the pits of marula fruit that they had eaten. From a cave alone, excavators saw 24 million marble stones.
“They really loved Marula,” says Stensmyr, who points out that the stones were found about 12,000 years ago about 8000 years ago. “During the times when these caves were inhabited, the San people must have taken huge amounts of marula in the caves.”
This means that Marula is likely to be stored there and available there long after the marula in the forest had eaten by wildlife. The strong smell of this whole marula would have attracted the flies.
To test whether wild flies would actually enter a cave, the research group placed birds with fermentation of marula along the outer wall of the Nswatugi cave. Surely for a period of a few days, these traps captured a number of D. melanogaster flying.
The study and story tells, quite happy with other researchers who study fruitflies.
“I especially liked walking and catching the flies in the painted caves,” says Kaufman. “It was inspired. It’s really a pretty paper.”
“I thought it was amazing,” said Celeste Berg, a development genetician at the University of Washington, Seattle, who has used flies in his research for 30 years. “I thought their data was really striking.”
Berg says she is wondering exactly how the flies would have spread from these caves to the rest of the world.
“I think it’s exciting to learn the origins of fruitflies and even if you’re not an ecologist or a folk geneticist, I think it’s only natural to be interested in the organism you’re studying,” Berg says. “I had assumed that fruitflies liked all kinds of fruits – especially bananas. I did not even understand that they preferred citrus. And it’s not even real citrus as they prefer, they prefer this special marulet plant, which I had never heard of. “
Debbie Andrew, a development biologist at Johns Hopkins School of Medicine, who has worked with fruitflies for four decades, also says she loved the paper.
” They built a good story, “said Andrew.” It’s a lot hard to prove something that happened 10,000 years ago or more. I like the story. “
If all details are correct, she says” I do not know, it probably seems, based on the amount of marula fruit stones they found in the cave. “
Based on this paper, Andrew says the old saying,” time flies like an arrow, and the fruit flies like a banana “should really change. ” Time flies like an arrow, “she says,” and the fruit flies like an orange or a marula fruit, or maybe an orange spiked with ethylisovalized. “