英语听力:自然百科 Dinosaur Mummy's Meal Revealed “恐龙木乃伊”面世(在线收听) |
With the exception of the trains that roll in the town a couple of times a day, the small ranch town of Malta, Montana is pretty quiet these days. The landscape is a far cry from what it was 77 million years ago when dinosaurs roamed the area. The now rolling grassy hills replaced rich rivers, rivers that scientists believe led to the death of many duck-billed dinosaurs. In the summer of 2000, paleontologists struck gold here, uncovering the most perfectly fossilized plant-eating dinosaur ever discovered and with almost all of its skin intact and fossilized. It would also give paleontologists their best evidence yet about the eating habits of plant-eating dinosaurs. They named the mummified dinosaur Leonardo, named after a piece of graffiti on a nearby rock. Joel Bartsch, the president of the Houston Museum of Natural Science, explains that because Leonardo died and was buried almost immediately, 90% of the body was preserved, including much of the dinosaur's skin and stomach contents.
What's really cool about Leonardo is that he was buried so quickly when he died that most of his skin, 90% of his skin intact, is found intact, still in place. And the thing that scientists are very interested in is that much of the stomach contents were preserved.
The contents of Leonardo's stomach are helping scientists establish what the habitat in which the dinosaur lived was like. Leonardo was approximately four years old, and would have been about twenty feet long, weighing around one ton. According to the Associated Press, scientists believe Leonardo died while trapped on a sandbar surrounded by high waters and that his body dried out before it was covered in sand. Over time, his body fossilized and is proven to be a virtual encyclopedia on plant-eating dinosaur digestion.
What makes it unique, what makes it incredibly exciting isn't the outer mummy but the inner mummy. Here's a hole, ripped through the gut wall, the side of the stomach and you can look through that, that hole. You can actually see the guts in work, at work. You can see the digestive process churning around. It's the very first dinosaur, plant-eating dinosaur ever found where you've got a window into a process of digesting and removing proteins and energy from the food.
Very little was known about what the duck-billed dinosaur ate since plant matter needs very special conditions to be preserved.
Looking at the teeth, we concluded it was grinding up the toughest vegetation available like a horse or zebra would. That's a theory, theory in anatomy. We didn't have the crime scene proof. We've got it now.
Leonardo has provided scientists a more complete picture than ever before of the dinosaur's ecosystem and environment just like a time capsule. The exhibit opens to the public at the Houston Museum of Natural Science in September. |
原文地址:http://www.tingroom.com/lesson/zrbaike/2008/254993.html |