国产热热热精品,亚洲视频久久】日韩,三级婷婷在线久久,99人妻精品视频,精品九热人人肉肉在线,AV东京热一区二区,91po在线视频观看,久久激情宗合,青青草黄色手机视频

Podcast

This croc could really chew


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

 

Get Flash Player

進入英語學習論壇下載音頻   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

(中國日報網(wǎng)英語點津 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.

濮阳市| 景宁| 三穗县| 遂宁市| 石城县| 城步| 资溪县| 涞源县| 开平市| 龙南县| 平利县| 泸溪县| 五台县| 襄城县| 青铜峡市| 广昌县| 香格里拉县| 义马市| 夏河县| 东宁县| 巴中市| 禄劝| 隆回县| 特克斯县| 柳江县| 米脂县| 固安县| 麻城市| 三原县| 娱乐| 东乌珠穆沁旗| 荣昌县| 高台县| 龙江县| 资兴市| 大渡口区| 丹凤县| 靖远县| 黔东| 宝坻区| 南汇区|