Learn about how scientists analyzed fast radio bursts to find the “missing matter” in the universe; why “discretion elimination” is more effective than implicit bias training; and how the femme fatale firefly lures mates to their doom.
Learn about how scientists analyzed fast radio bursts to find the “missing matter” in the universe; why “discretion elimination” is more effective than implicit bias training; and how the femme fatale firefly lures mates to their doom.
Scientists have found the 'missing matter' in the universe by Grant Currin
"Discretion elimination" is better than training for correcting implicit bias by Steffie Drucker
The femme fatale firefly lures males to their doom by Cameron Duke
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/a-better-way-to-stop-implicit-bias-the-murderous-femme-fatale-firefly-and-finding-the-universes-missing-matter
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about how scientists found the “missing matter” in the universe; why implicit bias training doesn’t work — and what to do instead; and how the femme fatale firefly lures mates to their doom.
CODY: Let’s lure you to some curiosity.
You may not have noticed, but the universe was missing a lot of matter. A team of scientists recently found it. According to their intergalactic research, there’s a mind-boggling amount of matter hanging out in the vast expanses of space between galaxies.
Scientists have put a lot of effort into estimating the total mass of all the normal, or baryonic matter they could detect in the universe — that’s all the matter that makes up the stars, planets, comets, asteroids, galactic dust...everything that isn’t dark matter or dark energy. They’ve also spent decades studying the infrared radiation left over from the early days of the universe, which gives them a rough estimate of how much matter should exist.
Here’s the awkward part: the two numbers are different. The objects we can detect only account for about half of the normal matter we think exists. Where’s the rest? That’s where the new research comes in.
The researchers relied on a mysterious phenomenon to make their discovery. Some galaxies emit short, powerful bursts of radio waves called fast radio bursts. We’ve talked about them on this podcast before. Fast radio bursts are a mystery of their own. But they still proved helpful in solving this mystery because they contain radio waves with different frequencies, the way white light contains electromagnetic radiation with different frequencies — also known as colors.
The high-frequency waves in fast radio bursts can pass through matter like it’s nothing. The interaction doesn’t slow them down much at all. On the other hand, the lower-frequency waves do slow down as they pass through matter. If all of the frequencies in a fast-radio burst reach us at the same time, we know it didn’t run into any matter. But if they don’t, we know there must be some matter out there.
The researchers knew there was a chance the missing matter was floating around undetected in the massive spaces between galaxies, so they pointed telescopes toward galaxies that emit fast radio bursts. Then they measured how long it took the high-frequency waves to travel to Earth and compared that with how long the trip took the low-frequency waves. Their measurements suggest that these radio waves are encountering quite a bit of matter as they pass through space that’s allegedly empty. That means that so-called “empty” space must contain matter that we just hadn’t detected before!
The matter isn’t dense — there’s about one subatomic particle per cubic meter — but interstellar space is so impossibly big that the new discovery doubles the mass of normal matter we know about in the universe. If only finding your missing car keys was this satisfying.
The US is having a moment of reckoning around discrimination and racism right now. As companies around the country scramble to demonstrate their dedication to diversity and equality in the workplace, you may have heard the term “implicit bias training” thrown around. Those training programs mean well, but the evidence says that another method called “discretion elimination” is more effective.
When we talk about implicit bias, we’re talking about the associations and stereotypes we hold about other people that we don’t even know about — they’re unconscious. They may not even align with what we say we believe. But even if we’re not aware of them, they influence how we interact with others, and they often lead to discrimination. And everyone carries some amount of implicit bias, whether you’re a preschool teacher, a podcaster, or a police officer.
But if you don’t know what your implicit biases are, how can you change them? That’s the million-dollar question. Because implicit bias is so deeply rooted in our brains, it’s extremely difficult to overcome. Experts have been trying to find a method to effectively eliminate implicit bias for decades, but nothing has worked in the long term. It’s not enough to just run a workshop to educate people about the concept — in fact, sometimes that can make implicit biases worse. Fortunately, another approach has proven more effective. It’s called discretion elimination.
Implicit bias elimination training aims to change someone’s thinking and decision-making process. Discretion elimination limits the information available to make the decision so implicit bias is never even an option. Here’s a classic example of this strategy in practice: In the 1970s, major symphony orchestras in the U.S. became concerned that they were only hiring musicians from a select group of music schools. So they started holding “blind auditions” where musicians auditioned behind a screen so they’d only be judged by their performance. Blinding the process didn’t just recruit more musicians from other schools — it also led the number of women in those orchestras to triple over the next 20 years. By removing unnecessary information about the musicians, the orchestras corrected a bias they hadn’t even noticed was a problem.
This is possible in all sorts of settings. Teachers can grade electronic assignments without checking the student’s name. Police can exclude a person’s race from their file before the prosecutor receives the case. Hiring managers can have applicants’ names and addresses removed before looking at their resumes. Discretion elimination is just one simple but effective step in the quest for liberty and justice for all.
Here in the US, it’s firefly season! Or do you call them lightning bugs? Either way, the warm glow of a firefly adds a little romance to a summer night. And I mean that literally: that glow is actually a mating call, and it’s how fireflies find love. That is, except for fireflies in the genus Photuris [foe-TOOR-iss], also known as the femme fatale firefly. They use their light to trap other fireflies and eat them.
Before I get into that, though, here’s some background on fireflies, in case you’ve never seen one. Fireflies are a type of beetle, and there are more than 2,000 species of fireflies worldwide. They literally glow. And that that glow comes from a chemical reaction between oxygen in the air and various chemicals in their bodies, especially bioluminescent compounds called luciferin and luciferase [loo-SIFF-er-inn and loo-SIFF-er-ace]. All fireflies light up as larvae, but many species lose the ability to glow as adults. That’s ok, though — they can spend up to two years in the larval stage but only a couple of weeks as adults. Most don’t even eat at that point.
Either way, the compounds that help them glow aren’t the only chemical trick up their sleeve. They also produce toxins called lucibufagins [loo-sah-BOOF-ah-jins] that discourage predators from eating them. That’ll be important later.
Common Eastern fireflies use their lights in a sort of dance. The male fireflies do something sort of like skywriting, where they make simple shapes in the air. Each species has a specific shape that the females find particularly sexy. In some places, whole populations of fireflies will flash in sync as if someone were flipping a light switch.
The ladies light up, too. If one likes a male’s dance, she will wave him over with a couple of flashes of her own light. During the mating process, he’ll pass his anti-predator toxins to her to help protect the mother and her eggs.
But sometimes, the female’s welcoming glow isn’t what it seems. The Photuris [foe-TOOR-iss] firefly lures males not for mating, but for murder.
In this genus, only the females light up as adults, and they use their light as bait for males of other species. They make a meal out of other fireflies for a very specific reason, and it’s not because they’re hungry. See, Photuris fireflies don’t make those anti-predator toxins. They have to steal them from other species to protect themselves. So when an unsuspecting male swoops down to share his toxins, WHAM — he’s dinner.
The next time you’re watching fields of fireflies light up the night, remember, there is a dark side. Some of those flashes are a deadly siren’s song.
CODY: See, and this is why it’s hard to say that I’d rather stay awake when I’m asleep. Cause everything is never as it seems.
ASHLEY: Let’s recap the main things we learned today
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CODY: Today’s stories were written by Steffie Drucker, Grant Currin, and Cameron Duke, and edited by Ashley Hamer, who’s the managing editor for Curiosity Daily.
ASHLEY: Today’s episode was produced and edited by Cody Gough.
CODY: Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!