Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren vogebam here. If you've ever swatted it
Speaker 1: fruit flies hovering over the fruit bowl on your kitchen
Speaker 1: counter and wondered what purpose they could ever possibly serve humanity,
Speaker 1: You're not alone. They are small, and they are annoying,
Speaker 1: but humans owe them a huge debt of gratitude for
Speaker 1: their contributions to the science of modern genetics. One species,
Speaker 1: in particular, Drosophila melanogaster, is a superstar of tiny, annoying
Speaker 1: winged things. At least five Nobel Prizes have been awarded
Speaker 1: to scientists for their work on fruit flies. Yes, the
Speaker 1: lowly fruit fly and the larger, glorious er human have
Speaker 1: together tackle genetics and done a lot of cool stuff.
Speaker 1: But like why fruit flies? And how do you keep
Speaker 1: them out of your kitchen? And do we need to
Speaker 1: blame scientists for them being in your kitchen? To begin with,
Speaker 1: fruit flies have been used in biological studies for a
Speaker 1: long time, which means there are a lot of tools
Speaker 1: and resources for scientists using Drosophila melanogaster to ask interesting questions.
Speaker 1: But there are some specific reasons. The species has always
Speaker 1: been a Darling of geneticists. For starters in genetics, it's
Speaker 1: helpful to have research subjects that can cycle through generations
Speaker 1: rather quickly, and fruit flies are great at that. We
Speaker 1: spoke via email with Thomas Merritt, PhD, Professor in the
Speaker 1: Department of Chemistry and Biochemistry at Laurentian University in Ontario, Canada.
Speaker 1: He said fruit flies create a new generation in about
Speaker 1: two weeks, making breeding them in the lab simple. They're
Speaker 1: also small and easy to rear and care for, and
Speaker 1: it's easy to house as many of them as you
Speaker 1: need in a single lab at one time. Also, fruit
Speaker 1: flies are surprisingly similar to humans and other vertebrates. Drosophila
Speaker 1: melanogaster has fourteen thousand genes, and we humans have somewhere
Speaker 1: between twenty thousand and twenty five thousand, and about eight
Speaker 1: thousand of those vans are analogous. Similarly, most fruit fly
Speaker 1: biochemistry is the same or similar to ours. Merritt said
Speaker 1: fruit flies are great to work on if you're interested
Speaker 1: in variation between individuals or genetic lineages. They are also
Speaker 1: a great system if you're interested in experimentally altering the environment.
Speaker 1: They are so small we can do things like keep
Speaker 1: thousands of flies at different temperatures to see how temperature
Speaker 1: changes metabolism or gene activity. In one study in my lab,
Speaker 1: we used a small conveyor belt to slowly turn the
Speaker 1: vials we keep the flies in. This simple instrument is
Speaker 1: essentially a fly treadmill, and we can get literally hundreds
Speaker 1: of flies exercising on a small desktop. But fruit flies
Speaker 1: can be annoying in a lab, just as they can
Speaker 1: in your kitchen, to begin with their small and it's
Speaker 1: very difficult to dissect a fruit fly in case you
Speaker 1: were wondering. And although we share many of the same
Speaker 1: genes and genetic networks, were separated from them by hundreds
Speaker 1: of millions of years of evolution. So it's hard to
Speaker 1: make assumptions about ourselves based on what we find in
Speaker 1: these little insects because there are substantial biological differences between us.
Speaker 1: Merritt said, there are certainly questions that are better asked
Speaker 1: in larger or evolutionarily more closely related species like rats
Speaker 1: and mice. Similarly, there are questions, for example, changes in
Speaker 1: genes through evolution that are better asked in organisms that
Speaker 1: are even smaller, can be kept in even larger numbers,
Speaker 1: and with even shorter lifespans like bacteria or fungi. But
Speaker 1: we can't blame scientists for the proliferation of fruit flies
Speaker 1: in the world. They would have been there regardless, Merrett explained.
Speaker 1: Drosophalo melanogaster is a cosmopolitan species, meaning it's found essentially
Speaker 1: almost anywhere we find humans. A fruit fly has pretty
Speaker 1: simple needs in order to prosper and multiply, and those
Speaker 1: needs are usually met in our homes, moderate temperatures and
Speaker 1: a source of fresh produce that's on the overripe side.
Speaker 1: This is why fruit flies live i on the hug
Speaker 1: in places like dumpsters, compost tapes, and kitchens. Marrett said.
Speaker 1: One interesting thing is we seem to see more flies
Speaker 1: inside in the early fall. I think that's from flies
Speaker 1: that have been happily breeding and multiplying outside all summer
Speaker 1: moving into the warmer inside spaces as the weather cools.
Speaker 1: The good news is that fruit flies aren't dangerous in
Speaker 1: any way. Merritt said. They don't carry disease, and they
Speaker 1: don't cause fruit to spoil or rot. At least Drosophila
Speaker 1: melano gaster doesn't, although there is at least one invasive species,
Speaker 1: the spotted wing fruit fly that actually damages fruit crops,
Speaker 1: and it's a growing agricultural concern. In my lab and
Speaker 1: in my house, we use a simple vinegar trap kenning
Speaker 1: jar with some vinegar in the bottom and a top
Speaker 1: of plastic wrap with a few holes punched in it
Speaker 1: to trap and remove flies. Today's episode was written by
Speaker 1: Joceline Shields and produced by Tyler Clang. For more on
Speaker 1: this and lots of other tiny topics with a huge impact,
Speaker 1: visit how stuff works dot com. Brain Stuff is production
Speaker 1: of iHeart Radio. For more podcasts for my heart Radio,
Speaker 1: visit the iHeart Radio app, Apple Podcasts, or wherever you
Speaker 1: listen to your favorite shows.