Quite why they do what they do is an absolute mystery. Well, it's a mystery to most of us, put it that way.
There's almost certainly bound to be some deeply introspective chap with a beard and appalling interpersonal skills locked away in a laboratory somewhere who's taken the time and trouble to nut it all out, but most of us wouldn't have a clue.
And, quite frankly, couldn't give a toss, either. We've got much more important things to worry about, like how the heck we're going to pay the psychic's bill now that it's clear we didn't actually win last Saturday's giant-jumbo jackpot $30 million.
It is questions of this nature that vex and perplex us, rather than any speculation about the life and times of those mute, mad and motile wee things we call sperm.
Yet we really should think a little more about those microscopic half-harbingers of life, if only because we owe our very existence to their deranged endeavours.
Or, more precisely, the deranged endeavours of one in particular, the winning sperm, the alpha sperm, the best and brightest sperm, the one who didn't go to Australia but chose to stay home and win the race.
Which itself is an extraordinary thing - the race, that is. Almost as extraordinary as the fact that there's no teacher looking on telling all the other wee sperm they're winners just for taking part.
But why it is that something roughly the size of an anorexic atom, with an IQ of less than a grain of sand, knows how to wriggle its tail and swim to a near-certain death like a suicidal Olympian is precisely the sort of question that should exercise an inquiring mind.
And the sooner the better, you'd have to say, since we've just learnt that the Lesser Spotted Kiwi Sperm is, apparently, dangerously close to appearing on same endangered species list.
Or so we discovered this week, with the release of a shock report showing that New Zealand's sperm count has halved in the past 20 years. Appalling as this is, what's even more alarming is the revelation that we don't know why.
Suffice to say, for some inexplicable reason, our sperm are dying off almost as quickly as those bloomin' snails on the West Coast. Alas, no one's showing the same concern for our vanishing sperm as they have for the imperilled gastropods.
Worried members of S.O.S. (Save Our Sperm) aren't picketing fertility clinics to demand better refrigeration. There's no public clamour for more gummint funding and no bank willing to pay for a special sperm sanctuary. We seem, in short, quite happy to let the frantic little wrigglers sink or swim.
One possible explanation for our indifference is that sperm do actually display the sort of collegial stupidity fallaciously attributed to lemmings. As any feminist will tell you - and any rural vet worth his or her AI straw confirm - it's extremely hard to keep sperm alive for any meaningful length of time.
Mainly because they're as daft as the blokes who produce them. You see, what happens is that sperm get so overexcited at the prospect of hurtling to oblivion that millions of them actually beat themselves to death with their own tails.
It's true! They wiggle so hard they kill themselves. Which doesn't really advance the argument for intelligent design but is a nigh perfect metaphor for most male behaviour.
"Oh, wow! This must be fun. It really hurts!!!!"
Any passing Martian struggling to make comprehensible otherwise inexplicable things like rugby, boxing, bodybuilding, tattoos, triathlons or the voluntary playing of bagpipes need look no further than this spermatozoic self-flagellation. It's in us, lads, whether we like it or not.
Worse still, the exigencies of fashion are compounding the problem. Tighter garments are subjecting the little wags to temperatures way in excess of the optimum. Our sperm are living in the reproductive equivalent of a sauna, which would surely increase the savagery of their assaults.
Then again, it's possible our dying sperm are just the canaries in a trousered mine. We've all seen those stories indicating that science can now efficiently do what nature alone could once achieve. The laboratory has replaced the boudoir as a locale of consummation. Blokes are entirely superfluous in the breeding department.
Perhaps our sperm have just realised the jig is up and simply decided, like the trilobites, to disappear into the mists of time.
If so, some 500 years hence, an intrepid navigator may sail across the steaming Pacific, brought to the boil by global warming, and discover faint traces of a vanished matriarchy on the remote shore of the abandoned land of Outer Roa.
And they may stand in awe and stare at the giant, enigmatic stone figures on the flanks of Rangitoto, faintly resembling the great obelisks of Easter Island, except these are huge and chiselled sperm, staring silently out on a silent sea, waiting forever for their egg to come.