ELI5: Explain Like I'm 5

The chicken or the egg

Well, imagine you had a little baby chicken and you wanted to know where it came from. Did it come from an egg or did it just appear?

Now, the truth is that all chickens come from eggs. Even grown-up chickens were once eggs themselves.

A long time ago, a special kind of bird laid an egg. And inside that egg was a little baby chicken waiting to grow up. When the egg was ready, the baby chicken pipped out of its shell and began its life.

As time went on, that little chicken grew up and passed on its genes to its own children. Those children came from their own eggs, just like their mother did before them. And so the cycle continues.

So to answer your question, the egg came first because all chickens come from eggs. Without eggs, there wouldn't be any chickens!
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