What is the number one sexual fantasy? How many couples are in sexless marriages? And does sex for humans last longer than it did for T-Rex? The answers may surprise you. A new book by David Baker, science writer and visiting lecturer at the University of Paris-Sorbonne, tells all.
1. Our most intimate and romantic experience may have begun as a form of cannibalism
Why have sex when you can just continue the 1.8 billion-year process of cloning (where organisms reproduce exact copies of themselves)? A lack of food as the earth froze to -50C caused the microbial blobs which then populated the planet to cannibalise each other. In such simple organisms, this may have resulted in an accidental mixture of DNA of predator and victim — creating the first cells with two parents, and conferring potential genetic advantages.
2. Men have always been desperate to prove their worth
Early female reptiles invested more energy in producing eggs than males did in producing sperm; as a result females were, generally speaking, more choosy in selecting a mate. So, males evolved methods to impress – turning their skin vibrant colours, performing a sort of courtly dance and even using their front legs to affectionately stroke females’ faces.
3. T-Rex had a 36-inch penis — but they were 330 ft (100m) tall.
Sex lasted just one minute.
4. The ‘Orgasmic Epoch’ — when placental mammals began to orgasm — dawned 66 to 55 million years ago.
Orgasms were nature’s way of incentivising mammals to reproduce, on the basis that this pleasurable consequence of sex would encourage them to do it again and again.
5. Millions of years ago when mammals were in constant fear of predators, the orgasm was a welcome chance for complete relief from fear.
In males the orgasm resulted in physical shuddering at lightning speed while brain activity slowed down and fear and anxiety evaporated. Females meanwhile experienced pulses that built in intensity and an even more thorough and complete absence of fear and anxiety.
6. One early side effect of the orgasm in mammals was a state of ‘collapse’ which also had a biological function.
Whether it lasted a few seconds or a few minutes the collapse was there to facilitate the passage of sperm and fertilisation of egg.
7. This is why the French call the moment of orgasm la petite mort, or ‘the little death’.
When it comes to sex outside of a committed relationship, only 10 per cent of women orgasm, compared with 68 per cent of those with a monogamous partner
8. A clitoris has 8,000 to 9,000 nerve endings — two to three times as many as in the penis.
All to help the conception, as the more nerve endings the bigger the post-coital ‘collapse’.
9. The clitoris evolved from the internal reptilian penis – kept inside the body for reasons of safety.
Ninety per cent of a woman’s clitoris resides internally.
10. A female hyena’s clitoris is as long as a male’s penis.
11. Masturbation is widespread across the animal world.
Lions and tigers are known to enjoy it. Some species of monkeys pleasure themselves with their tails. Elephants are known to get each other off with their trunks.
12. Bonobo monkeys masturbate every couple of hours and initiate sexual contact with a partner every 90 minutes.
Females frequently indulge in so-called tribadism (or ‘scissoring’) — rubbing their genitals against those of other females.
13. Female bonobos are highly invested in their sons and micromanage their sex lives.
There is no rape or infanticide within bonobo communities but there is incest and paedophilia.
14 Orangutan sex lasts an average of 15 minutes.
Gorilla sex lasts only one minute, while chimps get it over with in seven seconds, lest they be interrupted by a rival.
15. Average chimp penis girth is 5cm, while average human girth is 11.7cm.
The male human penis thickened over time, driven by sexual selection to favour female sexual pleasure and facilitate pair-bonding. Chimpanzee penises (although similar in length) are extremely thin by comparison.
16. It is likely that trans or and non-binary people existed among the Palaeolithic forager populations.
17. Bisexuality has existed for half a billion years.
18. Promiscuity and infidelity were common in human foraging bands.
Today approximately 20 per cent of men and 15 per cent of women cheat on their partners.
19. In today’s online dating, women gravitate towards only a small 15 per cent of men that are deemed to be most attractive.
This 15 per cent tend to be tall, handsome, high earning and photogenic, the so-called 6, 6 and 6 — 6ft, six-figure income, six-pack.
20. Ancient civilisations were tolerant of homosexuality.
Aztecs, Mayans and Incas all seem to have permitted homosexuality. The Babylonian ancient legal text, the Code of Hammurabi, even makes provisions for some women to marry other women, while in Mesopotamia homosexuality appears in art and male on male sex seems to have played a part in religious rituals. In Medieval Japan, Samurai were allowed to take young boys as lovers, but only one at a time.
21. Numerous Christian kings, Islamic sultans, and even a 9th-century Caliph were probably gay.
Ancient Greek mores held that the penetrator should be more masculine and/or higher status than the lover. Gay sex was only looked on negatively if the higher-ranking, or older person was on the receiving end.
22. In some cases gay lovers were allowed to be equals.
The Sacred Band of Thebes were a group of soldiers who were encouraged to take each other as gay lovers in the hope they would then fight more ferociously on the battlefield.
23. A man’s social standing used to be based on how pleasurable sex with his wife was.
In Ancient Rome, pleasurable marital sex was a cornerstone of virility, thus affecting the husband’s status. In India, pleasurable sex was viewed as essential to the bonding of man and wife.
24. Red Light Districts used to be a legal requirement.
In 19th-century France, brothels were required to put up a red lantern at their entrances, signalling they were a house of ill repute.
25. From the mid-15th century, the printing press was first used in Europe for making copies of the Bible and religious sermons but swiftly moved on to pumping pornography around the continent.
26. With the birth of motion pictures came the arrival of porn films.
The first, a striptease, was made in France in 1895. The first ‘hardcore’ porn films were produced in Argentina in 1905.
27. Number one among sexual fantasies is dominance and submission and S&M (sadomasochism), scenarios which may involve physical bondage, hence the umbrella term BDSM.
More than two thirds of adults — 68 per cent — have fantasised about BDSM scenarios, according to a 2017 Belgian study. It also revealed that nearly half of all adults claim to have engaged in BDSM sex practices at least once.
28. The proportion of people engaging in BDSM on a weekly basis (12.5 per cent) is roughly the same percentage of the human population with brown hair.
Those who engage on a semi-regular basis (26 per cent) is the same percentage of the population with Type A blood.
29. Foot fetishes are common, particularly among men.
At its core is a mixture of ideal mate selection and sexual rejection. A man finds a woman who is an extremely desirable mate. So attractive are her various attributes that he feels his own sexual market value makes him worthy only of her feet. And by idolising her feet, the sexual allure of the rest of her is intensified.
30. Sex before marriage took off in World War II with mobilisation of women into the workforce.
Almost half of Western middle-class women experienced premarital sex between 1940 and 1945, when there was a 29 per cent spike in unwed teen pregnancies — and an uptick in the number of sexually transmitted diseases.
31. The popular imagination exaggerates the number of young people in the 1960s and 1970s who were ‘hippies’ or ‘swingers’.
In fact they probably only made up 1.5 to 3 per cent of the population compared to the much more straitlaced majority. But their prevalence in all kinds of media forever reshaped public attitudes toward sex as a form of entertainment and pleasure.
32. Four out of ten adults in the developed world are neither married nor cohabiting.
The number of single people in the developed world doubled between 1960 and 1970.
33. In 2019, an average of 45 per cent of singles under the age of 40 reported that they were not looking for a committed relationship.
This was roughly equal for men and women.
34. An estimated 20 to 25 per cent of millennials (born 1981–1996) are projected to never get married, and that number is expected to be even higher for Gen Z (born 1997–2012).
The reasons? The sharp decline of in-person socialisation among younger people, with a consequent decline of in-person flirtation. Internet dating tends to be more selective and exclusionary than hooking up at a club or bar. Not forgetting the rise of free porn, substituting for real life sexual encounters.
35. Casual sex dropped by 14 per cent between 2007 and 2017 for millennials and Gen Z.
And in the same period the number of people under 30 reporting no sex in the past year almost doubled.
36. An alarming estimate of two in five men have begun using Facebook and Instagram as a masturbatory aid.
Around one-third of famous female celebrity accounts and up to 63 per cent of amateur model accounts are followed by men likely to be using them for masturbatory purposes rather than for celebrity gossip, make-up tips and ads for coconut water.
37. Erectile dysfunction is now experienced by approximately one in every four men under 40 (24.5 per cent).
This is a huge increase from the year 2000 when only 2 to 3 per cent faced similar issues, according to the Reward Foundation. Excessive porn use is the cause. Essentially, men are becoming so overstimulated by using pornography that sweet, romantic sex with a woman they are lucky enough to actually meet is not sustaining their arousal.
38. The couples most likely to get divorced are those who work in urban service industries.
The least likely? Those who live in the countryside and work in farming. The difference is a staggering 400 to 500 per cent.
39. If a woman is a stay-at-home mother, the divorce rate halves.
If the man is a stay-at-home dad, it doubles.
40. Fifteen per cent of married couples under 40 are sexless, and 30 per cent have sex less than once a month.
It’s not surprising sex, or a lack of it, is a key reason for divorce in the modern world.
41. You’re 45 per cent more likely to get divorced if you meet in a bar or club.
42. Dating apps are used by more than twice as many men (70 per cent) as women (30 per cent).
Women still prefer to meet men offline via work, friends or on a night out.
43. Two-thirds of men said they would never approach a woman they don’t know in public, according to a 2022 survey.
Fear of rejection, being branded a creep or harasser, and a dependence on online dating have combined to create this majority.
44. Yet they don’t have much luck online either — women swipe right (for yes) just 12.5 per cent of the time, compared to 65 per cent of the time for men.
45. Male sexlessness is at record levels: more than one in four men under 30 (28 per cent) have not had sex in the past year, and 17 per cent of men under thirty are virgins.
46. When it comes to sex outside of a committed relationship, only 10 per cent of women orgasm, compared with 68 per cent of those with a monogamous partner.
47. Of those 68 per cent of women who experience orgasm with a monogamous partner, only six in ten do so every time they have sex, according to a 2015 survey.
Eighty per cent of women cannot orgasm without clitoral stimulation.
48. The average number of sexual partners for women under 30 has doubled in the past thirty years.
49 Nearly half of 30 to 45-year-old women in the developed world are single.
If current trends continue, the proportion of people who never find a long-term partner may increase to 50 per cent or even two-thirds of the population of the developed world by 2100.
50. Sex may eventually become unnecessary.
Some believe we will one day develop a method of cultivating sex cells (sperm or eggs) from other cells in the body, allowing anyone to have children with anyone — even with themselves. The cells of dead friends and relatives could be used to produce children. Theoretically you could take someone’s DNA and procreate without their consent — for example, grab some skin cells from your celebrity crush after they’ve left a restaurant and make a baby together.
Adapted from The Shortest History Of Sex by David Baker (Old Street £14.99). © David Baker 2024. To order a copy for £13.49 (offer valid to 02/03/24; UK P&P free on orders over £25) go to www.mailshop.co.uk/books or call 020 3176 2937.