综合一区欧美国产,99国产麻豆免费精品,九九精品黄色录像,亚洲激情青青草,久久亚洲熟妇熟,中文字幕av在线播放,国产一区二区卡,九九久久国产精品,久久精品视频免费

Podcast

This croc could really chew


Updated: 2010-08-05 14:46
Large Medium Small

 

Get Flash Player

進(jìn)入英語學(xué)習(xí)論壇下載音頻   去聽寫專區(qū)一展身手

Scientists on Wednesday announced the discovery of an ancient, mammal-like crocodile that knew how to chew, something its modern gash-and-gulp cousins can't do.

The 100-million-year-old reptile, unearthed in Tanzania, was about the size of a domesticated cat and more at home on land than in water.

It had an unusually lean profile, a flexible backbone and relatively little scaly armor around its midriff, the better to leap in the air to grab giant dragonflies and other airborne prey.

But the most bitingly distinctive feature of Pakasuchus kapilimai, the researchers said, was its choppers.

It shared the overhanging, fang-like canines that today's alligators and crocodiles use to rip into their victims' flesh before swallowing them more-or-less whole.

But it also had specialized teeth that looked suspiciously like the molars once thought to be unique to our distant warm-blooded ancestors.

"At first glance, this croc is trying very hard to be a mammal," quipped Patrick O'Connor, a professor at Ohio University in Athens and lead author of the study, published in Nature.

"A number of characteristics of this new species are very similar to features that were critical during the course of mammalian evolution from the Mesozoic into the Cenozoic," which began 65 million years ago, he said in a statement.

The discovery adds to a growing body of evidence suggesting that crocodiles were once far more diverse than they are today in body type, habitat and appetites.

The diminutive croc would have co-existed with carnivorous theropods such as Tyrannosaurus rex and Velociraptor, as well as the huge, plant-eating Sauropods.

O'Connor and colleagues found a complete skeleton of Pakasuchus in Tanzania's Rukwa Rift Basin in 2008, and have also recovered portions of seven different individuals.

The new crocodile's name comes from "paka", the Swahili word for cat, and "souchos," Greek for crocodile.

Questions:

1. How old is the reptile?

2. Where was it unearthed?

3. What does the crocodile’s name of “paka” mean in Swahili?

Answer:

1. 100-million-year-old.

2. Tanzania.

3. Cat.

去聽寫專區(qū)一展身手

(中國日報(bào)網(wǎng)英語點(diǎn)津 Helen 編輯)

This croc could really chew

About the broadcaster:

This croc could really chew

Lee Hannon is Chief Editor at China Daily with 15-years experience in print and broadcast journalism. Born in England, Lee has traveled extensively around the world as a journalist including four years as a senior editor in Los Angeles. He now lives in Beijing and is happy to move to China and join the China Daily team.

赣州市| 海南省| 高平市| 花莲市| 南平市| 英吉沙县| 阿瓦提县| 博白县| 桐庐县| 庆城县| 兴业县| 东阿县| 县级市| 乳山市| 家居| 昌乐县| 莒南县| 永泰县| 建始县| 涡阳县| 汝州市| 栖霞市| 临沭县| 连云港市| 滕州市| 图木舒克市| 子洲县| 大同市| 宾川县| 濮阳县| 拜城县| 石台县| 昆明市| 虞城县| 昭通市| 秦安县| 武宣县| 青岛市| 麦盖提县| 安丘市| 泸溪县|