纪录片《进化缺环》 第18期 推翻观点(在线收听

If you look at the limbs what you find is that the joints are all angled

你可以看一下四肢,它们的关节都呈直角

so that the limb would have stretched out just to the sides.

所以四肢伸出来时只能贴住身体两侧

There's just no way that it could have brought its leg underneath to take any weight.

它不可能把腿放到身体下面支撑体重

Similarly with the hind limb, which we found a bit later on, similar kind of arrangement,

我们稍后发现,后肢也是同样的情况,也有类似的结构,

no ankle to speak of, just a paddle like limb.

没有所谓的踝部,长得和桨一样

Acanthostega's legs would have been useless for walking

棘螈的腿根本不适合于行走

and what's more, although it was a fully formed tetrapod it could never have lived out of the water.

另外,尽管它是完全成形的四足动物,它却不能离开水生活

It had gills just like a fish.

它长着和鱼一样的鳃

It meant the evolution of our legs could never have had anything to do with walking on land.

这意味着腿的进化应该和陆上行走毫无关系

Jenny Clack's discovery of the acanthostega had changed everything.

Jenny Clack发现的棘螈改变了一切

The old explanation that we'd evolved our legs after a fish came onto land just could not be true.

原来解释说腿的进化发生在鱼登陆之后,现在看来也并不正确

So the thing that has really changed is that rather than the fish

所以真正的演化过程并不是

going onto the land while it's, it's still got fins we've turned that completely on its head,

鱼带着鳍爬到陆地上,我们已经从根本上推翻了这一观点

so now we've got tetrapods in the water, still in the water, while they've got limbs with digits.

我们现在认为四足动物仍旧在水中,在水里进化出腿和趾。

  原文地址:http://www.tingroom.com/lesson/jlpjhqh/534292.html