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  • This episode of SciShow is sponsored by Brilliant!

  • Go to Brilliant.org/SciShow to learn more.

  • {♫Intro♫}

  • Some animals go to some extreme lengths to woo their partners.

  • For the male Amazon white bellbird, that apparently meansscreaming at them.

  • Loudly.

  • Uh, make that very loudly.

  • Because according to research published this week in Current Biology, these birds hold

  • the new world record for loudest bird song.

  • The Amazon white bellbird is a small white bird found in the mountainous regions of Brazil's

  • Amazon rainforest.

  • And it didn't just hit the loudest note, it destroyed the defending champ, the aptly

  • named Screaming Piha.

  • The bellbird's eerie, almost electronic calls can be 125 decibels in volume.

  • That's on par with ambulances and thunder!

  • But surprisingly little was known about them prior to this report.

  • Previous fieldwork from Brazilian researchers did note that they have unusually thick ribs

  • and abdominal muscles, which could suggest the ability to make loud sounds.

  • But no one had tried to measure them.

  • So, the team went in with advanced sound recording tools and video cameras to gauge the birds'

  • volume and learn more about their songs and their bodies.

  • The audio tools allowed them to measure the volume of the bellbird's song very precisely,

  • which is a tricky thing to do when you're studying them from a distance.

  • Meanwhile, their video cameras zeroed in on their relevant anatomythings like breathing

  • musculature and the shape of the throat.

  • And they found that not only does this little bird sing louder than any others recorded

  • to date, it's louder than mammals much larger than it, including bison and howler monkeys.

  • The video suggests they pull this off by opening their mouths really widely and gulping in

  • air.

  • Though, there are limits to their volume.

  • To get record-breaking loudness, they have to keep their songs brief.

  • And that might be because the birds are so small.

  • They only weigh about 250 grams, which is similar to a fully grown hamster.

  • So the researchers think their respiratory system is just too little to push around the

  • volume of air needed to sustain super loud noises.

  • Though, they'll need to conduct a bit more research on the bird's anatomy to confirm

  • all that.

  • While they're at it, they also hope to figure out why the birds sing so loudly.

  • See, the males don't just yell into an empty void hoping females will hear them.

  • They sing their loudest sounds when a female is on the same branch.

  • After she lands, they swivel their heads towards their potential and scream right at her.

  • Which is especially weird, given that his song is so loud, it could damage her hearing!

  • It's also unclear why the females put up with this.

  • Though, the team thinks they might be willing to suffer to get a better look at their potential

  • mate.

  • It's even possible the loudness itself is a signal of quality somehow.

  • Until there's further study of their anatomy and behavior, we won't really know.

  • In other bird-related newswell, I guess it can count as bird-related

  • Because scientists are getting closer to lab-grown chicken sandwiches!

  • Regular viewers might remember from our deep dive on artificial meats that one of the hardest

  • traits to replicate is the texture of muscles.

  • Well, in a study in the journal Science of Food published earlier this week, a team of

  • scientist-chefs managed to do just that.

  • And they say their success could lead to a world where we get to have sustainable meat

  • products without killing animals.

  • Almost 15% of our greenhouse emissions come from the livestock industry.

  • So, lots of efforts are trying to convince meat-lovers to cut back.

  • But not everyone is willing to give up their tender, juicy steaks.

  • So, one alternative is to grow meat in labs.

  • Studies suggest such facilities would take up less land and emit a lot less CO2.

  • Plus there wouldn't be any slaughtering involved.

  • But for it to really sell, lab-grown meat can't just taste like meat.

  • It also has to feel like meat when you're chewing it.

  • Most animal muscle is made up of long, spindly muscle fibers that are arranged into bundles.

  • These are the grain you see on when you cut into your steak or chicken breast, and they

  • give meat its unique texture.

  • And they've proven really tough to mimic.

  • So the research group behind the new study took a bit of inspiration from regenerative

  • medicine studies.

  • After all, if scientists can grow synthetic organs for transplantation, they ought to

  • be able to grow synthetic muscles.

  • So the team used a technique called scaffolding, where living cells are grown a preexisting

  • structure of some kind.

  • But the scaffold needed to be edible, in this case, and they needed an inexpensive and efficient

  • way of getting a lot of it.

  • So, they tried a food-safe gelatin that can be spun into tiny fibers.

  • And it worked!

  • When they put rabbit and cow muscle cells on the stringy gelatin scaffolds, they grew

  • into long, spindly fibers, just like in actual muscles.

  • Mechanical testing even showed that the texture of the new meat product was comparable to

  • real meatthough it didn't contain the same density of muscle fibers.

  • That means the lab-grown version might taste and feel like real meat, but it won't have

  • the same nutritional content.

  • So that's another challenge in the quest for a better meat alternative.

  • And while we don't have cultured chicken, steak, or bacon just yet, this new scaffolding

  • technique is an exciting step in that direction.

  • Thanks for watching this episode of SciShow News!

  • We hope you learned something new and exciting.

  • And if learning new things is something you want to do more often, you might also like

  • today's sponsor: Brilliant.org

  • Brilliant has dozens of courses about science, engineering, computer science and math.

  • So whether you're interested in the basics or diving deep into a complex topic, you're

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  • Like, I've been thinking a lot about trees today because we're joining the #TeamTrees

  • effort to plant twenty million trees by the end of the year.

  • And it turns out Brilliant's machine learning course has a whole chapter on them!

  • So it's about mathematical trees, like the kind you construct with genetic data to figure

  • out how species are related.

  • But still, I know I could use brushing up on that!

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  • subscription at Brilliant.org/SciShow.

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  • {♫Outro♫}

This episode of SciShow is sponsored by Brilliant!

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世界上最響亮的鳥兒對著它的配偶尖叫 | 科學秀新聞 (Loudest Bird in the World Screams at its Mate | SciShow News)

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