Human testicles and those of male chimpanzees are considerably larger than those of gorillas and orang-utans, two species of ape closely related to man. Gorillas and orang-utans have modest genitalia for their large body size and ejaculate relatively meagre amounts of sperm. These animals do not require abundant quantities of sperm cells for reproduction. The male, with his silvery coat, lords it over ‘his’ females in the gorilla harem, and other males rarely dare take him on. This ‘alpha male’ does allow other males to have sex, but only with immature or pregnant females. His imposing appearance ensures that the fertile adult females remain off limits to his subordinate fellow-apes. Although orang-utans also avoid a ‘sperm competition’, things are slightly different with them. These solitary orange-coloured giants, which roam the forests of Borneo, have a very restrained sex life.
Comparative anatomy — the fact of man’s proportionately huge testicles — indirectly illuminates the sex lives of our forefathers. Large testicles confer an advantage only where there is a sperm competition. Far back in evolution the competition to reach the ovum first was fought out between the sperm cells of various males. If two or more males mated with the same female within a few days, the one who ejaculated the largest quantity of vigorous sperm cells had the advantage in fathering descendants. Just as a car race is won by the driver with the best car, the male who mounts the female at the right moment, ejaculates most and in addition has very vigorous sperm cells, has the best chance of winning the contest. This isn’t perverse: ultimately there can only be one winner, usually a type comparable with a Bugatti Veyron car, with a top speed of 400 kph and unbelievable acceleration — the envy of some male gynaecologists, so I’m told.
In Farewell Waltz Milan Kundera describes a cunning gynaecologist with a long nose, who treats married, childless women in a very questionable way. He gives artificial insemination using his own sperm. His professional ethics are deplorable, and he is definitely not a great lover, but genetically Kundera’s doctor is the great winner. He has sired many long-nosed children for numerous happy, but deceived fathers. . . In the mid-1980s a gynaecologist in The Hague also inseminated women with his own sperm, which created a great commotion in the pages of a prestigious medical weekly. There are probably many of his offspring walking around The Hague and its environs. No trace of the inseminations, with ‘fresh’ instead of the usual medically checked and approved frozen sperm, could be found in the hospital records and the story was finally hushed up in a way so often convenient for doctors.
For every human being fathered in a normal way — which nowadays is no longer the case with a substantial number of people — it remains an odd idea that one has originated from one of the millions of spermatozoa that made a beeline for a single ovum. What would have happened if there had been another winner? The British cultural critic, writer and poet Aldous Huxley (1894-1963) expressed it as follows in a well-known poem (‘Fifth Philosopher’s Song’, 1920):
A million million spermatozoa,
All of them alive:
Out of their cataclysm but one poor Noah Dare hope to survive,
And among that billion minus one Might have chanced to be Shakespeare, another Newton, a new Donne —
But the one was Me.
It was said of the Marquis de Sade that he always carried a pillbox of sugared ‘Spanish fly’ with him, which he offered to unsuspecting prostitutes. Spanish fly was considered a powerful aphrodisiac, which stimulated, for example, the mucous membranes of the sex organs. This was how De Sade won his sperm wars. Research has been carried out in Britain showing that men who are aware of or suspect sexual unfaithfulness by their partners produce more powerful sperm.
Jealousy is at the same time one of the most debilitating, hate- provoking and destructive emotions. In Shakespeare’s A Winter’s Tale, Leontes, the king of Sicily, becomes totally unbalanced. Jealousy wrecks his whole life. In fact, Leontes, despite his jealous suspicions, should have taken comfort from the fact that his wife, Hermione, was pregnant. But instead every time she leaves the stage with their guest Polixenes, the king of Bohemia, Leontes becomes more distraught, more furious and more irrational. Finally he convinces himself that the child his wife is carrying is not his but the Bohemian’s and obsessively examines the face of his son Mamillius for any sign of a resemblance to his Bohemian guest. Inconsolable at the doubts surrounding his paternity, Leontes orders the murder of Polixenes. He has his wife imprisoned and his son Mamillius is denied access to his mother. In prison Hermione gives birth to a daughter, whom Leontes orders to be taken into exile and abandoned. Mamillius, deprived of his mother, dies of grief, and Hermione herself falls into a death-like coma. Leontes’ jealousy has destroyed not only his family but himself too: distrust and suspicion have ruined him. No one can console him or restore his confidence.
Tigers, bears and some primates do exactly the same as Leontes: they kill any young they think have been fathered by another male and so create more space among the females for their own descendants to be borne and brought up. This form of sexual selection is of course not a sperm competition; on the contrary, it is the avoidance of one.