Listen to the programme and fill in the gaps
Some of the weirdest animal behavior is about romance. That's especially true with birds — they 1.______ or dance or display a brilliant 2.________/ _______/ ________ to seduce the reluctant.
This sort of 3._________/ __________ display apparently has a long 4.__________: There's now new evidence that some dinosaurs may have used the same come-on.
The source is a kind of dinosaur that was built like a 400-pound ostrich. It lived about 75 million years ago and is called ornithomimus, meaning "bird mimic."
Scientists in Canada found the 5.________/ ___________ of one in 1995 that looked different from what they'd seen before. It had mysterious markings on the forearms. Two more were found recently with even more pronounced markings. When paleontologist Darla Zelenitsky took a 6._______/ _______/ ______ them, she was surprised. "We were finding these winglike structures in these relatively primitive dinosaurs," she says. The markings were the 7.__________ of primitive feathers.
Now, by no means did this 8._________________ fly. But Zelenitsky says the feathers would have formed a sort of winglike 9._____________ on the animal's forearms.
So why did these and other dinosaurs need feathers? This has been a point of debate among scientists, especially as more fossils from the dinosaur age are found with feathers 10.________. Did they need them to keep warm? To keep their eggs warm? Zelenitsky, who is a professor at the University of Calgary, noticed something unusual about three 11.___________ that suggested something else.
The juvenile ornithomimus had what would have been a thin, 12._________/ __________ and 13.__________. The two adults 14._________ the real thing — bigger, 15._________ feathers with 16.________.
"So because we are only finding them in the adult individuals," says Zelenitsky, "this suggests that the wings were used for purposes later in life, like reproductive activities for example, such as display or 17._________."
Now, the idea that these dinosaurs used feathers for a kind of sexy fan dance is a scientifically educated guess. After all, these things 18._______/ _______ tens of millions of years ago. But Richard Prum, an expert on birds present and past at Yale University, says recent discoveries do suggest that feathers were some kind of 19._________.
"The idea is that these were for communication," says Prum, "and that's fascinating, because we recently have new evidence that the feathers of dinosaurs were pigmented, and perhaps pigmented very 20.________, so that already implied that there was a communication function for early feathers."
In fact, Prum says the need for dinosaurs to "look hot" had some important consequences for today's birds. "The evolution of attractiveness or beautiful 21.________ may have had an important role in the origin and early 22._____________ of feathers," Prum says.
This latest discovery is described in the journal Science. Prum says he expects it will encourage scientists to look harder for signs of feathers: "These are the kinds of things that would have been 23.___________ years ago." That's partly because 24._________ of feathers are easily destroyed during excavation. And even if you're looking for them, they're easy to miss.
But these are the first 25.____________ dinosaurs found in North America. So clearly, they're buried here somewhere ... waiting for another chance to 26.________/ ________.
KEY
1. croon ( /kruːn/ to sing something quietly and gently. E.g. She gently crooned a lullaby. Bobby Darren was crooning ‘Dream Lover’).
2. fan of feathers
3. mating game (mating sex between animals. E.g. The mating season. Ten matings produced forty-six puppies.)
4. pedigree ( /ˈpedɪɡriː/ 1 knowledge of or an official record of the animals from which an animal has been bred. E.g. dogs with good pedigrees (= their ancestors are known and of the same breed) 2 a person's family history or the background of something, especially when this is impressive. E.g. She was proud of her long pedigree. The product has a pedigree going back to the last century.
Come-on: an object or action which is intended to attract somebody or to persuade them to do something.
E.g. She was definitely giving him the come-on (= trying to attract him sexually).
5. fossilized bones
6. close look at
winglike: resembling a wing
7. remains
8. ostrich-on-steroids
9. appendage /əˈpendɪdʒ/ a smaller or less important part of something larger. Sp. extremidad, añadidura, apéndice. E.g. The two appendages hanging from the insect's mouth are used to detect and taste food. He treats his wife as no more than a mere appendage.
10. attached
11. specimens (specimen: /ˈspesɪmən/ example of sth.)
12 downy coat
Downy (/ˈdaʊni/ covered in something very soft, especially hair or feathers. Sp. pelusa)
Coat the fur, hair or wool that covers an animal's body. Sp. pelaje. E.g. a dog with a smooth coat. Animals in their winter coats (= grown long for extra warmth).
13. stripy (/ˈstraɪpi/ with stripes. Striped. E.g. a stripy jumper)
14. sported (sport something to have or wear something in a proud way. Wear. Sp. lucir. E.g. to sport a beard. She was sporting a T-shirt with the company's logo on it.)
15. showy (so brightly coloured, large or exaggerated that it attracts a lot of attention. ostentatious /ˌɒstenˈteɪʃəs/ . E.g. showy flowers
16. quills (quill (also quill feather) a large feather from the wing or tail of a bird.
17. courtship /ˈkɔːtʃɪp/ the special way animals behave in order to attract a mate for producing young animals. Sp. cortejo. E.g. courtship displays
18. went extinct (extinct /ɪkˈstɪŋkt / no longer in existence. E.g. an extinct species. To become extinct. The red squirrel is in danger of becoming extinct in England. The fossilised remains of extinct animals.)
19. signal
20. boldly ( /ˈbəʊldli/ that can be easily seen; having a strong clear appearance. Sp. claramente, visiblemente, nítidamente. E.g. boldly patterned/ coloured)
21. traits (trait /treɪt/ a particular quality in your personality. E.g. personality traits. Awareness of class is a typically British trait.)
22. diversification /daɪˌvɜːsɪfɪˈkeɪʃn/
23. overlooked (overlook something to fail to see or notice something. Miss. Sp. pasar por alto. E.g. He seems to have overlooked one important fact. In my hurry to finish the exam I had overlooked part of one of the questions.)
24. traces (trace a mark, an object or a sign that shows that somebody/something existed or was present. Rastro. E.g. It's exciting to discover traces of earlier civilizations. Police searched the area but found no trace of the escaped prisoners. Years of living in England had eliminated all trace of her American accent. The ship had vanished without (a) trace.)
25. feathered (/ˈfeðəd/ covered with feathers or having feathers)
26. show off
Transcript
RENEE MONTAGNE, HOST: Some of the most fascinating animal behavior is really all about romance. That's especially true with birds. They croon or dance or display a brilliant fan of feathers to seduce a reluctant mate. The peacock is a good example. This sort of mating game display apparently has a very long pedigree, going back to the dinosaurs, as NPR's Christopher Joyce reports.
CHRISTOPHER JOYCE, BYLINE: There used to be this kind of dinosaur that was built like a 400-pound ostrich. It lived about 75 million years ago and is called Ornithomimus. Scientists in Canada found the fossilized bones of one in 1995 that looked different from what they'd seen before. It had mysterious markings on the forearms. Two more were found recently with even more pronounced markings. When paleontologist Darla Zelenitsky took a close look at them, she was surprised.
DARLA ZELENITSKY: We're finding these wing-like structures in these relatively primitive dinosaurs.
JOYCE: The markings were the remains of primitive feathers. Now, by no means did this ostrich-on-steroids fly, but Zelenitsky says the feathers would have formed a sort of wing-like appendage on the animal's forearms.
So, why did these and other dinosaurs need feathers? This has been a point of debate among scientists, especially as more fossils from the dinosaur age are found with feathers attached. Did they need them to keep warm, to keep their eggs warm?
Well, Zelenitsky, who's a professor at the University of Calgary, noticed something unusual about these three specimens that suggested something else. The juvenile Ornithomimus had what would have been a thin, downy coat and stripy. The two adults sported the real thing: bigger, showy feathers with quills.
ZELENITSKY: So because we're only finding them in the adult individuals, this suggests that the wings were used for purposes later in life, like reproductive activities, for example, such as display or courtship.
JOYCE: Now, the idea that these dinosaurs used feathers for a kind of sexy fan dance is a scientifically educated guess. After all, these things went extinct tens of millions of years ago. But Richard Prum, an expert on birds present and past at Yale University, says recent discoveries do suggest that feathers were some kind of signal.
RICHARD PRUM: The idea is that these were for communication. And that's fascinating, because we recently have new evidence that the feathers of dinosaurs were pigmented, and perhaps pigmented very boldly. So that already implied that there was a communication function for early feathers.
JOYCE: In fact, Prum says the need for dinosaurs to look hot had some important consequences for today's birds.
PRUM: The evolution of attractiveness or beautiful traits may have had an important role in the origin and early diversification of feathers.
JOYCE: This latest discovery is described in the journal Science. Prum says he expects it will encourage scientists to look harder for signs of feathers.
PRUM: These are the kinds of things that probably would have been overlooked years ago.
JOYCE: That's partly because traces of feathers are easily destroyed during excavation. And even if you're looking for them, they're easy to miss. But these are the first feathered dinosaurs found in North America. So clearly, they're buried here somewhere, waiting for another chance to show off.
Christopher Joyce, NPR News.
(SOUNDBITE OF MUSIC)
MONTAGNE: This is NPR News.
Listen to the programme on the NPR website
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