Ella Al-Shamahi is a Brummie, born to a Yemeni Arab family. From a strict Muslim upbringing she transitioned (evidently con brio, as ‘dick’ appears in her new book) to the secular life. She is now an author, explorer, academic paleoanthropologist, stand-up comedian and television presenter. This is an impressive c.v., deserving many congratulatory handshakes.

But wait. Alas, the handshake has become taboo. Your hand, says the Mayo Clinic, is a lethal bio-weapon crawling with pathogens as yearning to contaminate as those scary airborne droplets. Your hand is a horror story. According to one calculation, a square centimetre of manual skin contains ten to the power of seven bacteria. Even the common cold virus survives on unwashed hands for up to three hours.

But while any discussion of the handshake’s past and future has special resonance in the era of the elbow bump and the ankle wiggle, Al-Shamahi’s beguiling book has a more general claim to attention than merely being an account of the crisis in manners that Covid has made. It’s in that pleasing genre of pop anthropology also occupied by, say, Angus Trumble’s 2004 book, A Brief History of the Smile.

The common wisdom that the handshake originated in the Middle Ages to demonstrate that the shaker did not have Chaucer’s ‘knife beneath the cloak’ is quickly disproved by Al-Shamahi. She has found a Mesopotamian relief from the ninth century BCE in the Iraq Museum in Baghdad looking very much like a hand-shaking ritual. There are, she says, references to handshakes in Homer. In fact, the hidden weapon theory is no older than an 1870 article in Harper’s. Meanwhile, in 1901, Leon Czolgosz approached President McKinley, inviting a shake with one hand, then shooting him with a gun cloaked in the other. As they say in Zen, whatever is true, the opposite is truer.

The past year has freed us from many compulsory public intimacies, to the great relief of the insecure. Handshakes are specifically forbidden; but no longer do we have the tribulations of whether or not to air-kiss and if so on which cheek to start and for how long to continue. But the handshake is so fundamental to our culture that something important will be lost if it disappears from daily life.

Middle-class boys — more so than girls — were taught the moral and aesthetic necessity of a firm, dry shake. It was a gesture conveying mixed, but always benign, messages of greeting, approval, confidence and fraternity. Besides, when shaking hands it is almost impossible to avoid the shakee’s eyes. By the same score, a limp, damp shake is a bummer. I’ve never taken Graham Greene seriously since I was told his proferred hand was disgustingly soft and wet. One imagines Hemingway with a dry-as-dust bone-crusher. But the question of contagion is ever-present. When asked ‘May I shake the hand that wrote Ulysses?’, James Joyce replied: ‘Certainly not. It did other things as well.’

Yet anthropologists cannot decide if the handshake is a universal that transcends cultures. Evidence is mixed. Certainly the Maori nose-rub remains a local preference. And the penis-shake as a salutation has not gained any traction beyond Australia’s Walbiri tribe. Chimpanzees shake, but oriental humans do not. Recent research has shown that all skin movements excite the vagus nerve, which is connected to everything, the previously cited dick included. It seems we may be programmed to shake.

What is certain is that hands are unusually articulate. That famous drawing of 1508 by Dürer in the Albertina, Vienna shows praying hands intense with emotion. Adam reaching for God’s hand on Michelangelo’s Sistine ceiling would not have been the same if it had been an elbow bump. In 1963 the Italian designer Bruno Munari wrote an entire book about hand gestures: Supplemento al dizionario italiano. For most Italians, the hand gesture is a second, if not a first, language.

The multiple meanings of the handshake are proved in the breach as much as the observance. To refuse an offered hand is a devastating insult. No respecter of conventional manners, although deeply invested in illiterate germophobia, Donald Trump dislikes shaking hands. However, in a rare act of self-discipline, he trained himself to tolerate the risk to the point where an epic 29-second shake took place with Emmanuel Macron at their first meeting. On their third, they kissed.

Culturally speaking, the handshake exists somewhere between etiquette and germ-management. It is one of the only tactile gestures available to us which invites intimacy without also suggesting predatory erotic interest. And devotees learn to enjoy the refinements: the handshake combined with the reciprocal forearm clench is one to be reserved only for the most profoundly sincere encounters.

Ultimately, when this is all over, we will have to make a bargain between the handshake’s emotional benefits of contact and its accompanying risk of contagion. Al-Shamahi has written a book that is cheerful, witty and well-researched. Of her subject she says it is ‘dirty, unhealthy and banned’ — and looks forward to its return. So do I. Shake on it. Or maybe, if things don’t improve, hand on heart.