Learn about how astronauts may build the first moon base with help from their own urine; how musicians and audiences synchronize their brain activity; and more than you ever thought you wanted to know about narwhal tusks.
Learn about how astronauts may build the first moon base with help from their own urine; how musicians and audiences synchronize their brain activity; and more than you ever thought you wanted to know about narwhal tusks.
Astronauts may use their own urine to help build the first moon base by Cameron Duke
Musicians and their audiences sync their brain activity by Grant Currin
Why do male narwhals have tusks? Because the ladies love 'em by Grant Currin
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/using-urine-to-build-a-moon-base-musicians-and-audiences-sync-brain-activity-and-why-size-matters-for-narwhal-tusks
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 astronauts may build the first moon base with help from their own urine; how musicians and audiences synchronize their brain activity; and more than you ever thought you wanted to know about narwhal tusks.
CODY: Let’s satisfy some curiosity.
Building a moon base sounds like the stuff of science fiction, or maybe something a supervillain would be into. But in fact, there are tons of scientists and engineers working hard to make this a reality right now. It won’t be easy, and the potential solutions are going to have to be creative and weird. You’re about to learn about one of those solutions, and it involves… astronaut pee.
Here’s the deal. A good moon habitat is obviously going to have to be insulated and airtight. We don’t want anyone burning, freezing, or suffocating up there. Less obvious, but still crucial, is protection from solar radiation. The simplest solution might be to build habitats out of thick concrete. But that poses its own problems.
The good news is that most of the ingredients for concrete are already there. Lunar soil will do just fine for making concrete. But we’d want to 3D print the container, and to do that, we’d need to soften the concrete mixture using compounds called plasticizers.
That’s where the astronaut pee comes in. Urine is made mostly of water and a chemical called urea [yuh-REE-uh], and researchers have discovered that urea makes an excellent plasticizer. That’s because urea is great at breaking the hydrogen bonds that bind water molecules to other molecules. And of course, the other main component of urine is water, and that’s another key ingredient in concrete. Given that the price tag to send something as light as a soccer ball to the moon is around $10,000, this sort of thinking is as necessary as it is ridiculous.
Establishing a human presence on the moon will give scientists the opportunity to develop and field-test what we’ll need for a mission to Mars, which is the ultimate goal. But it’s good to remember that space travel is not all Matt-Damon-planting-potatoes-style glamour. The path to Mars may be paved with blood, sweat, and tears… and apparently, astronaut pee.
CODY: Well, that’s one way for astronauts to mark their territory
Think of the last great concert you went to. Maybe the crowd sang along, or clapped to the beat, or moved with the music. Good performances can make us sync with other people, and according to a recent study, that syncing can also happen deep within us — at a neural level. Yes, musicians and their audiences appear to actually synchronize their brain activity. And how much it happens may predict how much the crowd is enjoying the music.
For this study, the researchers used brain imaging techniques to discover what they call inter-brain coherence between musician and audience — in other words, synchronization of brain activity. They used a technique called near-infrared spectroscopy to monitor the brain activity of a professional violinist as he played twelve short pieces. Then they did the same to sixteen women while they watched videos and listened to the performance. The women also rated how much they liked each piece.
Sure enough, the researchers saw the same activity in the brain of the violinist as they did in the brains of the listeners.
Two of the regions where activity increased were the right inferior frontal cortex and the postcentral cortices. Those areas are said to be part of a region called the mirror-neuron system, and that’s what potentially makes this result a pretty big deal. The mirror neuron system is mostly hypothetical at this point, and a little controversial. But proponents say it’s a specialized group of neurons that activate in response to other people’s actions, to sort of “mirror” what’s going on in their brains. The researchers wrote in their study that, quote, “the frontoparietal mirror neuron system allows audiences to experience or comprehend the mind of the performer as if they were to ‘walk in another’s shoes,’” end quote.
The researchers also found that the inter-brain coherence was stronger when the participants listened to a piece of music they liked more — and that suggests that this technique could be used to judge the popularity of a performance. But there was a small catch: that pattern only emerged during the second half of each piece. The team thinks this could be because a listener has to get familiar with a piece before they can fully judge how they feel about it.
But the next time you find yourself swaying with the crowd at a show, remember: your brains are syncing up, too.
Narwhals are a type of Arctic whale, and people love ‘em because of one notable feature: the tusk. Male narwhals have a spiraling tusk jutting out of their forehead that makes them look like magical unicorns of the sea. And now scientists know why the tusk is there. Let’s just say that for narwhals, size most definitely seems to matter.
The narwhal’s tusk is actually its left canine tooth, which grows out of its head and can extend more than eight feet, or two and a half meters. But scientists weren’t sure exactly what the tusk was for. This might seem like an easy question to answer — just observe narwhals for a while and see how they use their tusks! But narwhals spend most of their lives hidden under the Arctic ice. They’re infamously hard to spy on.
But we may now know the answer, thanks to Zackary Graham, a Ph.D. student in evolutionary biology. He realized that we might not have to spy on them at all. The clues might be right there in narwhal skeletons.
Graham studies a type of natural selection called sexual selection, which deals with the evolution of traits that help species survive not by living longer, but by having more offspring. That is, traits that help an individual compete for mates. A male peacock’s flamboyant feathers are a classic example of a sexually selected trait. They don’t help the peacock survive — they help him draw the eyes of potential mates.
Evolutionary biologists know that a telltale sign that a trait was chosen via sexual selection is variation from one individual to the next. Just like hood ornaments on a car vary more than wheels do, a sexually selected trait tends to vary a lot more than a trait that’s required for survival. Graham and his colleagues wanted to see if this pattern held for narwhal tusks. So they collected and analyzed data on 245 adult male narwhals and compared the size of their tusks to the size of their tails.
It turns out there’s a huge amount of variation from tusk to tusk. The tusks varied in length by a factor of four while the tails varied by just a factor of two. To put it another way, narwhals with the same size body can have tails that range from one and a half to three feet wide (or half a meter to 1 meter wide) but tusks that range from one and a half to eight feet long (that is, half a meter to 2-and-a-half meters long). That makes this study the strongest evidence yet for why narwhals have such prominent tusks: because the ladies love ‘em.
Let’s recap the main things we learned today
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CODY: Today’s stories were written by Cameron Duke and Grant Currin, 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!