英語(yǔ)聽(tīng)力：恐龍是怎樣煉成的—13

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-Will they peck me?

-They’ll peck at your rings.

-They really?

-And they’ll try to take them off if they’re gonna get hold. But they are not very strong at pecking.

-I want to feel your feathers. Now this might be what a dinosaur felt like to touch. That's really soft and lovely.

-Yes, just like a cuddly toy.

-Oh, I'm stroking dinosaurs. Yeah, get it off me. I think they too little like dinosaurs especially when you know that some dinosaurs were actually feathered.

-They certainly do. And those feathers are quite primitive and they structure a lot like some of the fossil feathers we find.

The similarities aren't just on the surface. We can get a much better understanding of ancient dinosaurs by looking at the anatomy of their modern relatives in depth. And a local farm has recently had to put down one of its ostriches. As an anatomist, I'm very used to dissecting cadavers.

-You know, I don't usually wear Wellington boots when I do dissecting. But this will be the first time that I'd ever dissected a bird, or for that matter, the descendant of a dinosaur. Why don't you talk me through the anatomy that we can see on the surface?

-That's a heel, the ankle joints. But birds walk with that, clear the ground, just like their dinosaur and ancestors did.

-And Really? Just two toes? And one main one?

-The middle toe is their dominant toe, just like, you know, a dinosaur, the third toe is the major toe of the foot.

And there are other similarities to their ancient relatives.

-I don't know if you can see this. But here is the tip of wing, right here. And there’s a lovely little claw coming of it.

-Yeah, so that's the end of one of the digits on their arms, on their wings.

-Yeah. And you know, just there is a relic of their ancestors.

But the real clues about dinosaurs come from seeing what the relationship is between a bird's muscles and its bones.

-Right away we can see some of the fine muscles here. You can see this lovely, red colour, beautiful beefy muscle.

-So based on dissections like this, how accurately do you think you can reconstruct the musculature of extinct dinosaurs?

-You can look at any bone and tell something about the soft tissue anatomy of the animal, from the scars, as they’re called, the muscle scars like ligament and tendon scars on the bones that areattachment points for all these things that we see here as soft tissue.