評論
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If we look at the tetrapod we have the pit now gone altogether
我們再看一下四足動物，凹陷已經徹底消失
and here's that lower blood vessel hole there in the tetrapod,
這里有個四足動物顎骨的下行血管出口
so in this respect livoniana kind of agrees with the tetrapod.
就這一點而言，文塔螈比較接近四足動物
On the other hand, we find that in the fish
另一方面，我們發現在魚的顎骨上
a bone from the outer surface of the jaw comes round down to here and ends
顎外面有一塊骨頭向下延伸，到這里就結束了
and it's, it abuts against another bone up here called the pre-articular.
與之毗鄰的這塊骨頭叫做前關節骨
In the tetrapod, the bone from the outer face comes all the way up here.
在四足動物的顎上，外面的骨頭一直延伸到這上面，
It forms a big tongue extending backwards so and it comes all the way up here beneath it, so quite a different arrangement.
形成巨大的舌床，從后面開始，一直延伸到這下面，所以是很不一樣的結構
Livoniana here has got the junction and the bone exposed on the surface
文塔螈有接合部，骨頭暴露在外面
just like the fish, so in this case livoniana agrees with the fish,
這和魚很相似，就這點而言，文塔螈比較接近魚
so as you can see depending on which characteristic you look at
因此，根據觀察到的這些特征
it either lies sort of halfway between or it agrees with the tetrapod, or it agrees with the fish.
它處于二者之間，它或者比較接近四足動物，或者比較接近魚，
Exactly what you would expect from an intermediate form.
正是人們期盼的中間物種
Ahlberg believes livoniana really is an elusive transitional form, almost exactly half fish and half tetrapod.
Ahlberg認為文塔螈確實就是難得一見的過渡型物種，幾乎就是半魚半四足類的動物
It is certainly the only fossil yet discovered that shows the process of change between the two actually taking place.
它是迄今發現的反映二者演變過程的唯一一塊化石。
