The Birds and the Bees?

I would like to know how the phrase 'the birds and the bees' ever came to imply what you use it for. We've been... or actually the boys have been (because I would just as soon avoid the conversation altogether) brewing up to this conversation for awhile. It started with easy questions like, 'Do babies have blankets in their moms tummies?' 'Did I have clothes on when I came out of my moms tummy?' These questions were some time ago, but they have continued with questions that a very simple answer would satisfy. Not so the other night. Charles was in one of his question asking modes, and he can ask tough questions. Let's just say that he was NOT satisfied with simple or vague answers but demanded details. Sweet Martha...the details. Henry laughed hysterically. And, Charles...our dear analytical, detail-oriented, so serious, little boy kept on asking...and asking... and asking. Nothing was funny to him...it just was. Of course, now he's moved on from that to breast-feeding.

So, a sample of our Charles' questions.
1) 'What is under the earth?' I questioned a little thinking he meant what was under the ground in the center of the earth. No. He meant that since the earth is round, like a ball, what is underneath it... like under Antarctica.

2) 'If the earth spins so fast, why doesn't it fly off into the sky?' Apparently his preschool teacher had been discussing gravity.

3) 'Why does God make it so bad storms happen and people get hurt or die?'

When he is wondering if something really happened or is just pretend, he will ask, 'Did that really happen down in this world?'