Pratica di Shadowing: Why Over 600,000 Bird Specimens Are Preserved At The Smithsonian | Colossal Collections - Impara a parlare inglese con i video

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The Smithsonian Natural History Museum houses over 600,000 bird specimens from the last 200 years.
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And new specimens are added each month, thanks to the detailed work of specialists who preserve, skin, and maintain every bird in the collection.
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But most of these birds never see the museum floor.
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So why do they need to be perfectly preserved?
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The answer?
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Research.
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Whether it's identifying birds killed by airplanes, or discovering evolutionary changes in duckbills.
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We're not just preparing this bird for use tomorrow.
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We're preparing this bird for use for hundreds of years now.
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We went to the Smithsonian to see how one specimen in the skins collection is added, prepared, and used for generations to come.
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It starts with acquisition.
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It says here on the label that this ostrich was sent by King Mendelik as a present to President Roosevelt.
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Specimens are usually donated by people or organizations.
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This California condor was donated by the U.S.
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Fish and Wildlife Service.
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This bird came from President Theodore Roosevelt's personal collection.
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And this Cooper's hawk died while crashing into a building window.
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It was donated back in 2017 and is about to get its spotlight in an upcoming exhibit.
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But it was initially stored in this freezer.
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So it's on the left shelf.
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From there, our hawk is taken up to the prep lab into the skilled hands of museum specialists like Christina and her husband Brian.
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Brian, did you do that?
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Yes, I did put the cotton in the mouth.
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a couple of fat.
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This specimen is 9,926.
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So I prepared at least that many birds and mammals.
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When you're at about 10,000, it shows that you've been doing it for at least probably 20 years or so.
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And you can do it blindfolded.
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It was a fun exercise and it actually worked.
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Blindfolded or not, the specialists first thaw, weigh, and measure the hawk.
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And then they pick up a scalpel to start separating the skin from the muscles and fat.
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Since these are going to be stored as dried specimens, we want to remove as much of the muscle from the specimen that we can.
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Brian removes the skin from the body of the bird, discarding the soft tissues and oil glands, which would cause the specimen to rot.
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And it's crucial to get every piece of fat out without damaging the skin, since these specimens are meant to last for years to come.
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That's where gentler tools, like his hands, become useful.
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You have to go very slow, methodical, to get the skin off without ripping it.
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I'm pushing the skin rather than pulling it so I'm not stretching it.
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Bryan also uses corncob dust throughout the process to absorb any body fluids so the specimen is kept clean.
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New people use a lot less dust, and more experienced people just cover it with dust.
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When removing the smaller parts of the bird, like the head or the eyes...
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The angle of the scalpel also makes a big difference.
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You notice I'm cutting away from the skin.
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There's been times where when you grab the eye, it squirts at you.
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Sometimes birds that have more fat on their skin need to go through additional cleaning.
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All this white goopy stuff, this is all fat.
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That needs to come off, otherwise it will get rancid and then it will acidify and it will literally just ooze out of the skin.
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They use this fat wheel machine to remove all the fat until you can see the feather track.
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This takes a little bit of practice because if you press too hard, you will rip the skin.
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Once the fat is cleared, more corncob dust is used to absorb the moisture, and then the specimen is washed and dried.
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You wanna see me blow the sawdust off?
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Okay.
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All right.
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So with this, we do it in the fume hood, because as you'd imagine, I'm gonna blow a lot of dust everywhere.
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Christina uses a forced air dryer to blow off the sawdust and a hair dryer to fluff up the feathers, adding a nice sheen to them.
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To get the bird presentation ready, Brian will first tie the wings together to create a limited range of motion.
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He approximates how far a Cooper's hawk would have naturally spread their wings.
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So in the future, if somebody grabs the bird and opens up the wing to see the underside of the wing, by tying it, it'll make the specimen stronger.
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Now the specimen is ready to be stuffed with cotton, recreating its original shape.
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We're trying to make a specimen that lasts forever and is strong.
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So I'm not a tailor or a seamstress, but I can sew up a bird pretty good.
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We get the feathers, make sure that they're arranged properly in the right order, so that'll assist researchers later.
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The last step is pinning the bird onto a board to dry into its permanent position.
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However I end up pinning it, that's the way it's gonna look the rest of its career at the Smithsonian.
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It takes probably close to 100 birds before somebody can go at it alone.
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Once they reach 1,000 birds, then we say that that person is generally an experienced preparator, and they can teach other people very well.
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After 10 or so days, this Cooper's hawk will be completely dried and ready to debut on the exhibit floor.
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The hawk will be just one of 20 specimens on display for the Lights Out exhibit, all birds who have died from flying into skyscraper windows.
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And they'll eventually join the larger Skins collection with over 470,000 specimens, helping researchers from all around the world.
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Like Lauren and Joshua, researching how mating between domestic and wild ducks has changed the size and structure of their bills.
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Or Jim, with the Feather Identification Lab team.
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He works with government agencies to identify birds killed during airstrikes.
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We get about 10,000 strikes a year.
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The busiest times are in the fall and the spring.
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And this place, the Division of Birds, is the perfect place for us to be because we have 80 percent of the world's bird species represented in this collection.
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So if there's a bird strike that happens in the world, we likely have a specimen to match it up to.
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This is a bird strike sample, the remnants of a bird aircraft collision that has been sent to us for us to identify.
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So I can see that we've got a couple wing feathers here, we've got a tail feather, we've got some body feathers.
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So we can actually take this feather out and match up these tail feathers quite well to the barn swallow.
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and we've got even these nice little peachy feathers that were doing this.
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His findings are sent to airfield biologists and engine manufacturers to adjust aircrafts and reduce accidents.
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This bird was collected back in 1878.
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And so this bird was collected before airplanes were even imagined and put into this collection.
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And now we're using it to identify a bird aircraft collision.
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So we never know what these specimens are gonna get used for, but that's really why it's important to keep them forever.
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A separate wings collection also helps for deeper analysis of feathers.
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Back in the old days, they didn't make too many spread wings or flat skins.
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And us in the feather lab really liked that because it allows us access to feathers that occur under the wing and access in different areas of the bird where we might get a feather to, but it's very difficult to get into a traditional museum skin.
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Other researchers might be exploring the microbiomes found in the wings, like Gary.
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He discovered that vulture wings have a bacterial group called Deinococcus, one of the toughest organisms that can withstand high radiation.
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So when I expose this wing into full sun, the temperature on a day like today would be 90 degrees outside.
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In about three minutes, the temperature on the surface of this wing heats up to over 160.
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And that probably explains why Dinococcus is so dominant, because it's one of the few bacterial groups that can actually reproduce.
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At the Smithsonian, these are just two of the collections within the bird division.
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There's also the organ collection soaked in ethanol for preservation, the skeletons with each bone meticulously numbered, and mounted birds that retired from being on the exhibit floor.
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All of these are time stamps of the present bird population, creating a record for future generations of researchers.
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When the first bird preparators prepared birds, they had no idea what DNA was.
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Even though they didn't know that, by doing a consistent bird prep, it has enabled future researchers to conduct research on birds.
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And, you know, I wish I had a time capsule to go into the future to see what our birds are gonna be used for 100 years from now.

Informazioni su questa lezione

In questa lezione, esploreremo il mondo della conservazione degli esemplari di uccelli al Museo Nazionale di Storia Naturale dello Smithsonian, un argomento affascinante per chi è appassionato di ornitologia e scienze naturali. Gli studenti avranno l'opportunità di praticare la pratica di conversazione in inglese attraverso la comprensione del processo di preparazione e conservazione degli esemplari di uccelli. Gli argomenti di vocabolario includeranno termini specifici legati alla tassidermia e alla conservazione, mentre il contesto di conversazione si concentrerà su come i ricercatori utilizzano queste collezioni per scopi scientifici e di ricerca, come l'identificazione di uccelli vittime di incidenti aerei e lo studio delle variazioni evolutive.

Vocabolario e frasi chiave

  • Specimen - Esemplare; si riferisce a un campione, in questo caso di uccello, preservato per scopi di studio.
  • Preservation - Conservazione; l'atto di mantenere un esemplare in condizioni tale da durare nel tempo.
  • Taxidermy - Tassidermia; la tecnica di preparare e conservare gli animali morti per esposizione o studio.
  • Acquisition - Acquisizione; il processo attraverso il quale un nuovo esemplare viene aggiunto alla collezione.
  • Thaw - Scongelare; il primo passo per preparare un esemplare congelato per la conservazione.
  • Research - Ricerca; studio scientifico che utilizza gli esemplari conservati per ottenere nuove informazioni.
  • Procedure - Procedura; le varie fasi seguite dai specialisti per preparare un esemplare.
  • Cleaning - Pulizia; l'operazione di rimuovere i tessuti molli e il grasso dall'esemplare.

Consigli pratici per questo video

Per chi desidera utilizzare questa lezione per la pratica di pronuncia e la tecnica di shadowing, è fondamentale prestare attenzione alla velocità di parola degli speaker. Il video è presentato in un linguaggio tecnico, ma la maggior parte delle informazioni è espressa chiaramente anche se a un ritmo sostenuto. Consiglio di ascoltare attentamente le frasi chiave, facendo delle pause frequenti per ripetere le parole e le espressioni, concentrandosi sull'accento americano che caratterizza il narratore. La difficoltà dell'argomento potrebbe richiedere una ripetizione più lenta di alcune parti, pertanto non esitare a rivedere il video e a praticare più volte per migliorare la tua fluenza in inglese e prepararti per eventuali esami come l'IELTS speaking. Questo approccio ti aiuterà a costruire una comprensione più profonda del lessico e delle strutture grammaticali in uso.

Cos'è la tecnica dello Shadowing?

Shadowing è una tecnica di apprendimento delle lingue supportata da studi scientifici, originariamente sviluppata per la formazione dei traduttori professionisti e resa popolare dal poliglotta Dr. Alexander Arguelles. Il metodo è semplice ma potente: ascolti un audio in inglese di madrelingua e lo ripeti immediatamente ad alta voce — come un'ombra che segue il parlante con un ritardo di solo 1–2 secondi. A differenza dell'ascolto passivo o degli esercizi di grammatica, lo shadowing costringe il tuo cervello e i muscoli della bocca a elaborare e riprodurre simultaneamente i modelli di discorso reale. La ricerca dimostra che migliora significativamente la precisione della pronuncia, l'intonazione, il ritmo, il discorso connesso, la comprensione dell'ascolto e la fluidità del parlato — rendendolo uno dei metodi più efficaci per la preparazione alla prova di speaking dell'IELTS e per la comunicazione reale in inglese.