What does the saying lets talk about ';the birds and the bees'; actually have to with the conversation????

I have just never understood why when parents are going to talk about sex to their children they refer to it as the birds and bees. If anyone knows why please let me know.What does the saying lets talk about ';the birds and the bees'; actually have to with the conversation????
Well, first off, that expression is SO outdated. But, the way interpret it is that birds are motherly and nurturing (so meaning women) and that the bees, ahem, think with their stingers. They pollinate the flowers and hop from flower to flower..kind of sexist ya think?What does the saying lets talk about ';the birds and the bees'; actually have to with the conversation????
well just think if you had children and have to explain to them about sex you wouldn't want to. no parents want to talk to there children about it..cause when they do they know the time is coming closer for them to b doin it and also letting go..
A different way of saying lets talk about sex. It's more operate to say birds and the bee's in front of kids than sex.
its just a way to use the term more nicely
It's on the same nonsensical level as ';the stork brings the baby';!