Which Came First, the Chicken or the Egg?

先有鸡还是先有蛋？

Believe it or not, this question dates back to ancient Greece, where philosophers used it as an excuse to argue about reasons and results. Some might say the chicken came first. The reason is that you can’t have an egg without a chicken to lay it. While others might argue that the egg came first, since all chickens begin life inside an egg.

Both of them seem to have a point, right? In fact, the question has a rather clear answer.

“It’s pretty simple,” said Jasmina Wiemann, an expert from Yale University. “The egg is much older than the chicken. Ancestors of chickens date back 21 million years. That sounds pretty ancient, but the egg has been around for hundreds of millions of years.” Scientists discovered a fossilized bird from northwestern China with an egg in its body. It’s the most ancient egg ever discovered.

信不信由你，这个问题可以追溯到古希腊，哲学家们以此为理由来阐释原因和结果。有人可能会说先有鸡，因为没有鸡下蛋，就不可能有鸡蛋。而另一些人则认为先有蛋，因为鸡的生命是在蛋里开始的。

这两种说法似乎都有道理，对吧？事实上，这个问题有一个相当明确的答案。

耶鲁大学的专家杰思米娜·维曼说：“答案很简单。蛋比鸡古老得多。鸡的祖先可以追溯到 2100万年前。这听起来很古老，但蛋已经存在了数亿年。”科学家在中国西北部发现了一块鸟化石，鸟的体内有一颗蛋。这是迄今为止发现的最古老的蛋。

The earliest eggs, however, would have looked quite different from those in your fridge. They would have been soft, kind of like turtle eggs you may see on beaches. The hard, protective coating came later.

By the way, you should know that egg-laying is part of humans’ evolutionary history. In other words, if you go back far enough in time, you might see our ancestors lay eggs. And women today still produce eggs through a process called ovulation. The eggs stay inside the human body and they’re very soft.

Strangely, some other mammals still reproduce by laying eggs, such as the duck-billed platypus and echidna.

Now, here’s a new question for you—which came first, the egg or the echidna?

不过，最早的蛋和冰箱里的蛋看起来很不一样。它们是软的，有点像你在海滩上看到的海龟蛋。蛋坚硬的保护层是后来形成的。

顺便提一下，你应该要知道，产蛋是人类进化史的一部分。换句话说，如果你回到足够久远的过去，你可能会看到我们的祖先产蛋。今天的女性仍然通过叫作排卵的过程产生卵子。卵子留在体内，非常柔软。

神奇的是，仍有一些哺乳动物通过下蛋来繁衍后代，比如鸭嘴兽和针鼹。

现在，有一个新的问题要问你——是蛋先出现，还是针鼹先出现？

Word Bank

lay v. 下（蛋），产（卵）

ancestor n. 祖宗；祖先

discover v. （第一个）发现

produce v. 生长；出产

process n. 过程；进程