Name: 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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基礎被動語態

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

For the male Amazon white bellbird, that apparently means… screaming at them.

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

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

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.

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 anatomy — things like breathing

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

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

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

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 news… well, 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

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

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

And they've proven really tough to mimic.

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

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

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

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

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

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 meat—though 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

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.

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