Evolutionary theory is primarily about survival but, as Jonathan Silvertown makes clear in this intriguing book,  as well as having survival value, laughter allows us to share in the fun.

The need to laugh seems to be universal. When I was a child my Uncle George told me, ‘Laughter is the best medicine.’ When, in later life, I told George that he was my favourite relative, he responded, ‘There wasn’t much competition.’ A sense of humour, it seems, runs in the family.

As a writer and avid reader of comedy, I often wonder why we laugh and especially what makes some jokes so funny while others fall flat.

In The Comedy of Error, Professor Silvertown deploys many of the world’s oldest jokes, coupled with some of our latest science, to unravel the similarities and differences in humour across cultures.

An evolutionary biologist and comedy buff, he reveals why laughter is contagious, why being funny makes men in particular seem sexier, why incongruity is often a trigger for laughter and why explaining a joke almost always makes it less amusing.

Yet as this clever piece of work demonstrates, while explanation usually deflates rather than enhances a joke, understanding how humour actually works can be extremely edifying.

As I learnt at university, the founder of psychoanalysis, Sigmund Freud, was a life-long collector of jokes. It is pleasing to note that Silvertown not only unpacks a squadron of puns and ‘Freudian slips’, but makes good use of Freud’s book, Jokes and their Relation to the Unconscious, first published in 1905.

Freud argued that jokes playfully juxtapose sense and nonsense. This at first puzzles, then enlightens the listener. As Silvertown puts it, ‘these (two key) elements can be recognized in most jokes. The set-up is the puzzle and the punchline is the enlightenment.’

An illuminating example comes from the American comic, Groucho Marx. Groucho’s joke begins: ‘One morning I shot an elephant in my pyjamas.’ This is the set-up. Then comes the punch-line: ‘How he got in my pyjamas, I don’t know.’

A second example is from the English entertainer, Bob Monkhouse :

‘They all laughed when I said I wanted to be a comedian. They’re not laughing now.’

A third is ‘A rabbi, a priest, and a minister walk into a bar. The bartender says, “What is this – some kind of joke?”’

Silvertown documents how the English-born proponent of evolution by natural selection, Charles Darwin, experimented on his infant children by tickling them. Darwin observed that the capacity for laughter in humans appears at a very young age. In his book The Expression of the Emotions in Man and Animals, published in 1872, Darwin demonstrated that animals, and in particular our nearest relatives, chimps and gorillas, laugh from four to five weeks old. This is especially when engaging in what Darwin called ‘tickle play’. Contending that spontaneous laughter in humans is ‘a call from our deep animal nature,’ Darwin concluded: ‘The imagination is sometimes said to be tickled by a ludicrous idea; and this so-called tickling of the mind is curiously analogous with that of the body.’ But, as Aristotle noticed, it is not possible to tickle oneself.

Following on from Freud and Darwin, Silvertown is particularly strong when he investigates laughter’s evolutionary origins and why the root of a good joke is almost always error.

One of my favourite examples of the latter is this verbal joke: ‘The Philharmonic Orchestra played Beethoven last night. Beethoven lost.’

Another is an anonymous one-liner: ‘I get enough exercise just pushing my luck.’

A final gag is from the American comic W. C. Fields: ‘Smile first thing in the morning. Get it over with.’

When he writes about stand-up comics, Silvertown explores why most comedians recognise the need to warm up an audience. As he puts it: ‘Once you are in the mood, you are much more likely to laugh at the next gag.’ Hence to increase mirth and hilarity, most stand-up comics aim to keep the gags coming thick and fast. But as comedians know all too well, success depends on timing.

In the strange-but-true department, there’s evidence that stand-up comics die young and much younger than other performers.

‘Worse still,’ writes Silvertown, ‘funnier comics die youngest of all, although why is not yet clear.’

A number of studies strongly suggest that stand-up comedy is an unhealthy profession. Memorably, the British comedian Tommy Cooper, who habitually wore a red fez while performing, died of a heart attack at 63 – live on television in the middle of a show.

Silvertown adds that no one, to his knowledge, has yet tested whether audience members live longer if they laugh more.

For the record, I’m pleased to report that LaughLab, an online survey of people in 70 countries that set out to discover the world’s funniest jokes, came up with one of my favourites: ‘I want to die peacefully in my sleep like my grandfather, not screaming in terror like his passengers.’

It is fitting that, as an evolutionary biologist, Professor Silvertown closes his captivating book with this line from 81- year-old American comedian, Lily Tomlin: ‘Instead of working for the survival of the fittest, we should be working for the survival of the wittiest – then we can all die laughing.’ Boom boom.