Turns out we’ve had it wrong about eggs and sperm. Well, not wrong, but we didn’t get the detail quite right.
We thought it was the fastest swimmer who got to the egg and did the job.
Not exactly. Turns out Mr. Successful is getting some help. Her egg is choosing the sperm and then giving him a leg up, as it were. (As opposed to a leg over, which we will get to in a minute.)
New research by really clever Swedish and English scientists shows eggs are selecting sperm by using little chemical attractants. Think of it like perfume, but on the molecular level.
The egg is actually drawn to the quality of the sperm. And it lets that selected sperm know it should swim faster and straighter.
Fast and straight, ‘cos that’s what the egg wants. Just saying! This is biology, folks. No political correctness going on down here.
And here’s something else the Swedish and English guys found. By the time of the choosing – that’s what it’s called in scientific circles: the choosing – there’s actually only about 250 sperm in the vicinity.
But let’s start this at the beginning. I know when comes to sex, you guys don’t like to rush things.
The beginnings are not only right there in the biology, but right here in this room tonight, this very comedy club.
It turns out -- this is a bit of a shock, so I hope you’re sitting comfortably --
It turns out that women don’t have to be very picky.
Because the actual choosing, genetically speaking, is not being made here in this very comedy club.
No sir! Let me explain…
There are two choosings. Yes, the first one is here, in this place where we are tonight. Hopefully a bar with a good selection of gin.
But here’s the weird science. It is only after the deed is done, the sex is had, the roll in the hay is over, the hanky panky complete, the bonking ended, the sausage hidden …
You guys may know some other scientific terms…
It is only then does the real work begin, the far more sophisticated process of the second choosing.
It is only after he’s rolled over, the female in the equation starts looking for desirable characteristics. He’s wondering what’s for breakfast but on the other side of the Sheridan, part two is already under way.
Let’s pause in this scientific exploration for a moment so I can break it down for you. During sex, a man sends an average 100 million sperm off to get her pregnant, to carry on the human race with his particular characteristics.
(And for some of us, it may be as many as 1.2 billion sperm per encounter, but this is not something the “some of us” should talk about. We are enormously modest about our enormous … fertility.)
But even a hundred million sperm. We are seriously going for quantity here, aren't we, men?
It’s the old male thing. And young male. When you don’t know what you’re doing, send lots. Everything you’ve got. One of them’s got to get lucky, right?
But the woman, she's got just one egg. Just one ovulating, receptive, yes-we-are-open-for-business egg. (let’s put the twin thing aside for now.)
One egg. So she gets to be choosy. She is going for quality here, not quantity.
But as I said, by the time of the actual choosing, we are already down to some 250 sperm. I know, I know … but we will get to the other guys later, trust me.
Now it’s come to chemistry, if you want to get precise. (Yeah, there’s chemistry between you, but it ain’t in the way you were thinking.)
So, chemistry. She has little receptors that can pick orange hair and roaming hands at 40 paces.
You, with the red hair and freckles over there, you’re dead to me. Mr. Buck Teeth, gone. Hello handsome with the receding chin and bad posture in the back. And goodbye.
On the other side of the Sheridan, she is giving her selected Mr. Right the inside track. Fast and straight, remember?
And even more interesting: to the also-rans of the 250 sperm that did make the journey, the Not Mr. Rights, the egg is telling them to swim slower.
She’s saying: Nah, take your time. Hitchhike, take a walk. Maybe you can catch an Uber. It’s all good. Bye. Call your mum!
As for the rest of the 100 million, well, I’m sorry to break it to you… they didn’t make it. I don’t know what happened.
Nobody has surveyed them to find out what went wrong. Gotta consider they are male, so they probably didn’t bring maps, didn’t think to ask for directions. Thought they may as well go back to the bar.
But it’s a reasonable question, right? What happened to the 100 million, minus 250, that didn’t go the distance? 
I think that’s a research task for some guys whose work is done now and really could use the job.
Like, you know, a couple of really smart English and Swedish scientists?