中国发现的250万年鳄鱼祖先化石表明鳄鱼也胎生

It was thought to only lay eggs but experts have provided the first ever evidence that an ancient ancestor of the crocodile also had live births.A remarkable 250 million-year-old fossil has been discovered which contains an embryo inside the mother.

鳄鱼一般被认为是只下蛋的，但专家提供了一个远古鳄鱼胎生的证据-----一个两亿五千万年前含有胚胎的母鳄鱼化石被发现。

The new fossil is from a distant ancestor of the crocodile that flourished in shallow seas of South China in the Middle birth is well known in mammals where the mother has a placenta to nourish the developing is also very common among lizards and snakes where the babies sometimes 'hatch' inside their mother and emerge without a shelled egg.

新化石来自一个生活在三迭纪华南浅海的远古鳄鱼。胎生在哺乳动物中是众所周知的，哺乳动物母亲具有滋养胚胎发育的胎盘。蜥蜴和蛇中也非常普遍有时婴儿在他们的母亲体内“孵化”而没有壳蛋的出现（蝮蛇等，也叫卵胎生）。

Until recently the third major group of living land vertebrates the crocodiles and birds only laid eggs.

直到最近，作为第三种主要的陆生脊椎动物：鳄鱼和鸟类都被认为是只下蛋的。

Researchers from Hefei University of Technology in China discovered the new fossil of an unusual long-necked animal called Dinocephalosaurus - a creature that flourished in shallow seas of South China in the Middle Triassic.

来自中国合肥工业大学的研究者们发现了新的化石——一种罕见的叫做“东方恐头龙”的长颈动物，这一生物在三叠纪中期时在华南浅海曾经大量繁衍。

An embryo was found inside the rib cage of the mother and facing forwards.

在恐头龙妈妈的胸腔里面发现了一个面朝前方的胚胎。

This suggests that the animal was not eaten - as swallowed animals generally face backwards because the predator swallows its prey head-first to help it go down its throat.

这表示这个动物可能不是被捕食的。通常被吃下的动物是面朝后的，因为食肉动物为了顺利吞咽那些被捕食的动物，经常先从脑袋吞起。