侏罗纪搏击俱乐部 第75期:鲸其实是有腿的

 　　Incredibly, whales are closely related to hoofed¹ animals, in particular, the pig and the hippo.

　　很难相信，鲸类跟有蹄类动物的关系非常接近，特别是，猪和河马。

　　55 million years, the actual evolutionary² origins of whales and which group of land animals they're most closely related to has been the subject of a lot of interest in recent years.

　　五千五百万年来，鲸实际的进化起源以及它们与哪种陆地动物最亲近，是近些年来吸引了很多兴趣的话题。

　　And, the paleontological evidence, the fossil evidence and evidence from looking at the DNA³ of living whales and other animals now really strongly points to whales being very closely related to hoofed mammals.

　　古生物学证据、化石证据以及对现代鲸类和其它动物DNA的研究结果现在真的有力地指向鲸类与有蹄类动物的亲缘关系非常接近。

　　We actually have found hind⁴ legs of walking whales.

　　我们确实找到了陆行鲸的后腿。

　　And the hind leg has what we call a double-trochleated astragalus.

　　其后腿上有我们称作双滑轮结构的距骨。

　　And this is an astragalus or an ankle bone, which has a both an upper and lower curved surface which allows the spring in the step.

　　这就是一块距骨或者说踝骨，其表面同时有向上和向下的弯曲，使之在走路时有弹性。

　　It allows a deer to jump a fence.

　　这使得鹿能越过栅栏。

　　And these earliest whales, which are walking whales, have that kind of hind leg.

　　这些最早的鲸，做陆行鲸，就有那样的后腿。

　　No other kind of mammal has that kind of hind leg.

　　没有其他的哺乳动物有那样的后腿。

　　But unlike the mega shark, the biting sperm⁵ whale lived in families called pods.

　　不过与巨型鲨鱼不同的是，噬抹香鲸以家族为单位成群生活。

　　Whales in general are social animals and sperm whales are too, they go in small groups.

　　鲸一般是社会性动物，抹香鲸也是，它们小群活动。

　　And, we would expect that, back in the Miocene, there were little pods of sperm whales, and we might also suppose that if they came under attack they might try to help defend each other.

　　我们可以想象，在第三纪中新世，抹香鲸就这样小群活动，而且我们也能推测如果它们受到攻击它们会帮助保护彼此。

　　There's huge advantages of hunting as a pod or as a group because you can do things as a group that you can't do as an individual.

　　小群或者成组狩猎能带来很大的好处，因为组群能完成个体没法做到的事情。

　　You can herd⁶ prey⁷, you can attack from multiple sides.

　　能够围赶猎物，能从多个方向发动攻击。

　　So I think, given the opportunity, they almost certainly would hunt in pods.

　　所以我想，要是有机会，它们大概一定会成群狩猎。

　　Working together in a pack, allowed the biting whales to be more successful hunters.

　　在鲸群里一起合作，使得噬抹香鲸成为更成功的猎手。

　　But becoming separated from the group could spell disaster.

　　不过要是跟鲸群分开就可能会是灾难。

　　Living in a pod and having such a massive body made them lethal⁸, but its name, the biting whale, describes its true source of power, the teeth.

　　成群生活加上那样一个庞大的身躯使它们危害极大，不过它的名字噬抹香鲸，描述了它威力的真实来源，牙齿。

　　What makes Brygmophyseter such an incredible whale is that it's got both upper and lower teeth, you look in that mouth, there's 44 teeth in there.

　　让四贺鲸成为如此奇鲸的原因是它上下颌上都有牙齿，你看看那张嘴里面，有44颗牙齿。

　　Now they're not the teeth of a cute loveable whale.

　　它们可不是可爱的小鲸的牙齿。

　　They are the same size as the teeth that you'd see in the mouth of Tyrannosaurus Rex.

　　它们的大小和在霸王龙雷克斯暴龙嘴里的一样。

　　They have large teeth.

　　它们有巨大的牙齿。

　　The teeth aren't wickedly serrated like teeth from the Megalodon or some of the other big sharks. But they're large blunt, kind of peg⁹ like teeth.

　　这些牙不像巨齿鲨或其它巨鲨的牙齿那样有狡黠的锯齿。而是又大又钝、像桩子一样的牙齿。

　　The teeth are interlocking, in fact, this tooth which I have of a related sperm whale shows where the opposite tooth came right down here and occluded¹⁰ against this crown.

　　这些牙齿上下交错，事实上，我这颗是它抹香鲸亲戚的牙齿，能看出来对面牙齿直接下来到这里堵住这个牙冠。

　　And this is very typical of these fossilized teeth.

　　这是这些牙齿化石非常典型的特征。

 

1 hoofed   

adj.有蹄的，蹄形状的，装蹄的v.（兽的）蹄，马蹄( hoof的过去式和过去分词 )

参考例句：

• He was hoofed out of the Guards. 他被开除出警卫队。 来自互联网
• He hoofed his way to town. 他步行去了城里。 来自互联网

2 evolutionary   

adj.进化的；演化的，演变的；[生]进化论的

参考例句：

• Life has its own evolutionary process.生命有其自身的进化过程。
• These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。

3 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 hind   

adj.后面的，后部的

参考例句：

• The animal is able to stand up on its hind limbs.这种动物能够用后肢站立。
• Don't hind her in her studies.不要在学业上扯她后腿。

5 sperm   

n.精子，精液

参考例句：

• Only one sperm fertilises an egg.只有一个精子使卵子受精。
• In human reproduction,one female egg is usually fertilized by one sperm.在人体生殖过程中，一个精子使一个卵子受精。

6 herd   

n.兽群，牧群；vt.使集中，把…赶在一起

参考例句：

• She drove the herd of cattle through the wilderness.她赶着牛群穿过荒野。
• He had no opinions of his own but simply follow the herd.他从无主见，只是人云亦云。

7 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

8 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

9 peg   

n.木栓，木钉；vt.用木钉钉，用短桩固定

参考例句：

• Hang your overcoat on the peg in the hall.把你的大衣挂在门厅的挂衣钩上。
• He hit the peg mightily on the top with a mallet.他用木槌猛敲木栓顶。

10 occluded   

v.堵塞( occlude的过去式和过去分词 )；阻隔；吸收（气体）

参考例句：

• Lymphatics are occluded with fibrin. 淋巴管受纤维蛋白阻塞。 来自辞典例句
• A blood clot occluded an artery to the heart. 血块阻塞动脉的核心。 来自互联网