VOA慢速英语2021--脚印显示一些两腿恐龙动作敏捷

Footprints Show Some Two-Legged Dinosaurs² Were Agile³

New research on dinosaur¹ footprints unearthed⁴ in Spain adds to growing evidence that a dinosaur that was genetically⁵ similar to the Tyrannosaurus rex was extremely agile. The Tyrannosaurus rex was a very large meat-eating dinosaurs that was not agile.

The findings were published on December 9 in "Scientific Reports," which covers natural sciences. The findings announced the existence of sets of fossilized dinosaur footprints that prove the dinosaur could move quickly.

These footprints join other sets found in Utah and Texas. One of the sets there shows dinosaurs running at speeds over 48 kph. The Spanish footprints showed speeds of nearly 45 kph.

To figure out the running speed, scientists measured the length of the footprints and then considered the height of the place where the dinosaur's legs meet the body, or the hip⁶. They also needed to consider the distance between one footprint and another on the same foot.

All the known sets of prints that show speed come from a family of dinosaurs called theropods. These carnivorous, or meat-eating, dinosaurs stood on two legs and could not fly. They are like the famed velociraptor, a dinosaur seen in many famous movies.

The researchers estimated that the animal that created the most recent set of footprints was probably 1.5 to 2 meters tall and 4 to 5 meters long from mouth to tail.

Scientists think there may be faster dinosaurs, but these footprints have been easier to find. The footprints are known as tracks when there are one or more long sets.

"Behavior is something very difficult to study in dinosaurs," said lead writer Pablo Navarro-Lorbés of the University of La Rioja. "These kind of findings are very important, I think, for improving that kind of knowledge."

Scientists usually predict dinosaur behavior through computer modeling of the animals' movement. Physical examination of fossilized footprints confirmed the results.

These are "clearly active, agile animals," said Smithsonian paleontologist Hans Sues, who was not part of the study.

Words in This Story

dinosaur – n. one of many reptiles⁷ that lived on Earth millions of years ago

agile – adj. able to move quickly and easily

fossil – n. something (such as a leaf, skeleton, or footprint) that is from a plant or animal which lived in ancient times and that you can see in some rocks

tail – n. the part of an animal's body that extends from the animal's back end

paleontology – n. the science that deals with the fossils of animals and plants that lived very long ago especially in the time of dinosaurs

1 dinosaur   

n.恐龙

参考例句：

• Are you trying to tell me that David was attacked by a dinosaur?你是想要告诉我大卫被一支恐龙所攻击？
• He stared at the faithful miniature of the dinosaur.他凝视著精确的恐龙缩小模型。

2 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》

3 agile   

adj.敏捷的，灵活的

参考例句：

• She is such an agile dancer!她跳起舞来是那么灵巧！
• An acrobat has to be agile.杂技演员必须身手敏捷。

4 unearthed   

出土的（考古）

参考例句：

• Many unearthed cultural relics are set forth in the exhibition hall. 展览馆里陈列着许多出土文物。
• Some utensils were in a state of decay when they were unearthed. 有些器皿在出土时已经残破。

5 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

6 hip   

n.臀部，髋；屋脊

参考例句：

• The thigh bone is connected to the hip bone.股骨连着髋骨。
• The new coats blouse gracefully above the hip line.新外套在臀围线上优美地打着褶皱。

7 reptiles   

n.爬行动物，爬虫( reptile的名词复数 )

参考例句：

• Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
• Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》