侏羅紀(jì)搏擊俱樂部 第75期:鯨其實是有腿的

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

很難相信，鯨類跟有蹄類動物的關(guān)系非常接近，特別是，豬和河馬。

55 million years, the actual evolutionary 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.

五千五百萬年來，鯨實際的進(jìn)化起源以及它們與哪種陸地動物最親近，是近些年來吸引了很多興趣的話題。

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

古生物學(xué)證據(jù)、化石證據(jù)以及對現(xiàn)代鯨類和其它動物DNA的研究結(jié)果現(xiàn)在真的有力地指向鯨類與有蹄類動物的親緣關(guān)系非常接近。

We actually have found hind legs of walking whales.

我們確實找到了陸行鯨的后腿。

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

其后腿上有我們稱作雙滑輪結(jié)構(gòu)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.

這就是一塊距骨或者說踝骨，其表面同時有向上和向下的彎曲，使之在走路時有彈性。

It allows a deer to jump a fence.

這使得鹿能越過柵欄。

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

這些最早的鯨，做陸行鯨，就有那樣的后腿。

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

沒有其他的哺乳動物有那樣的后腿。

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

不過與巨型鯊魚不同的是，噬抹香鯨以家族為單位成群生活。

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

鯨一般是社會性動物，抹香鯨也是，它們小群活動。

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.

我們可以想象，在第三紀(jì)中新世，抹香鯨就這樣小群活動，而且我們也能推測如果它們受到攻擊它們會幫助保護(hù)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.

小群或者成組狩獵能帶來很大的好處，因為組群能完成個體沒法做到的事情。

You can herd prey, you can attack from multiple sides.

能夠圍趕獵物，能從多個方向發(fā)動攻擊。

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

所以我想，要是有機(jī)會，它們大概一定會成群狩獵。

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

在鯨群里一起合作，使得噬抹香鯨成為更成功的獵手。

But becoming separated from the group could spell disaster.

不過要是跟鯨群分開就可能會是災(zāi)難。

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

成群生活加上那樣一個龐大的身軀使它們危害極大，不過它的名字噬抹香鯨，描述了它威力的真實來源，牙齒。

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.

讓四賀鯨成為如此奇鯨的原因是它上下頜上都有牙齒，你看看那張嘴里面，有44顆牙齒。

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

它們可不是可愛的小鯨的牙齒。

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

它們的大小和在霸王龍雷克斯暴龍嘴里的一樣。

They have large teeth.

它們有巨大的牙齒。

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 peg like teeth.

這些牙不像巨齒鯊或其它巨鯊的牙齒那樣有狡黠的鋸齒。而是又大又鈍、像樁子一樣的牙齒。

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 occluded against this crown.

這些牙齒上下交錯，事實上，我這顆是它抹香鯨親戚的牙齒，能看出來對面牙齒直接下來到這里堵住這個牙冠。

And this is very typical of these fossilized teeth.

這是這些牙齒化石非常典型的特征。