Selfie: Barack Obama and David Cameron pose for a picture with Denmark's Prime Minister Helle Thorning Schmidt.

Selfie: Barack Obama and David Cameron pose for a picture with Denmark's Prime Minister Helle Thorning Schmidt.

Are you a fomo sapiens? Judging by his behaviour at Nelson Mandela's memorial service last week, Barack Obama is a member of this new subspecies. So is Britain's Prime Minister David Cameron, who should know better. The ''fomo'' stands for Fear of Missing Out, a defining characteristic of a generation with itchy thumbs and short attention spans. Fomo sapiens cannot leave its phones, tablets or laptops alone, no matter how inappropriate the occasion. Checking your texts or updating your Facebook status during a funeral, for instance, or taking a happy-snap of yourself with a couple of mates during a memorial service. Those, I hope we can still agree, are times when the focus should be on the dearly departed, who has gone to that undiscover'd country from whose bourn no traveller returns. Until, that is, we get the first ''selfie'' from the Other Side. LOL!

Homo sapiens (wise humans) first appeared in the fossil record in Africa about 195,000 years ago. It seems only fitting that fomo sapiens (self-obsessed humans) appeared in Africa on Tuesday, in a rainy Johannesburg. The US President snuggled in close to Danish Prime Minister Helle Thorning-Schmidt, the political sphere's answer to Cameron Diaz, to make sure his smiling face was captured on her phone. Meanwhile, Mr Cameron launched himself into the frame from the right like a grinning dolphin at a water park.

Was this really a fitting way to mark the passing of prisoner 466/64, a man who, for 18 years, was kept by South Africa's white-supremacist regime in a cell measuring 2.4 metres by 2.1 metres? Nelson Mandela was allowed to send just one letter and receive one letter every six months - a deprivation inconceivable to fomo sapiens, who have to text, post or tweet once every six minutes to prove they are still alive.

Hang on, I hear you cry, aren't you being a bit hard on what was just a silly, casual photograph? Perhaps - but if the leaders of the free world don't know how to conduct themselves on a big occasion, what hope is there for attention-deficit teenagers soldered to their smartphones?

I'm with Michelle Obama on this one. As Barack, Helle and Dave larked about, Michelle, who was dignity personified in black lace, gave Barack the ''Wife's Death Ray Stare'' - the one that says, ''You may think you're having fun, buster, but just you wait till we get back to the room.'' Where Mandela was always dignified, the Obama-Schmidt-Cameron trio looked crass. Where Mandela was a highly disciplined grown-up, they looked juvenile and self-indulgent.

In August, Jason Feifer, a Brooklyn-based editor, started a gallery of Selfies at Serious Places on Tumblr. Feifer found a global parade of doe-eyed teens posing in front of Auschwitz, in corteges and crematoria, writing gems like: ''Love my hair today. Hate why I'm dressed up #funeral.'' The very worst picture - amid stiff competition - was of a boy gurning in front of a coffin with the caption: ''My friend took a selfie at a funeral and didn't realise his dead Grandma was in the background!''

On Thursday, Feifer announced he was giving up Selfies at Serious Places. Now that the President had appeared in a funeral selfie, ''my work is done,'' he said. However, Feifer refused to condemn the idiots who take funeral selfies, claiming that youngsters in previous generations would have done exactly the same if they had had smartphones. ''When a teen tweets out a funeral selfie, their friends understand that [they] are expressing an emotion they may not have words for. It's a visual language that older people simply don't speak,'' said Feifer.

I don't agree. The funeral selfie is not an expression of emotion; it's an evasion of emotion. When my grandfather was buried 25 years ago, I stood by the side of his freshly dug grave and I was drenched in sorrow. The soft thump of the earth my grandmother dropped on his coffin, the crack of the gravedigger's spade, the tears coursing down my face, the women keening all around me. This was death, that hard and serious thing: the dark backing to the mirror, as Saul Bellow beautifully called it. There was no chance to distract myself from grief; no beeping phone, no time to compose 140 characters, leaving room for a clever hashtag. No selfie to prove where I was or what I felt. Who needs a photograph when life itself has never been more vivid, or more devastating?

A study published last week claims that when we take a photo of something, we are less likely to remember it. ''When people rely on technology to remember for them - counting on the camera to record the event and thus not needing to attend to it fully themselves - it can have a negative impact on how well they remember their experiences,'' says psychologist Dr Linda Henkel.

What implications does this ''photo-taking impairment effect'' have for fomo sapiens, who photographs everything that moves without being moved, who texts fast, but has no time to think?

The great Cuban dancer, Carlos Acosta, said he believes there is a shortage of talent to succeed him because ''with phones, computer games and DVDs'', the younger generation of dancers is ''always distracted, always entertained''. Ballet, he said, by contrast, was ''very, very hard''.

Mandela knew the meaning of very, very hard. In one of his final interviews, Mandela said that, despite the hardship, his long years in prison had given him time to really think and expand his moral outlook on the world. He became the free spirit, ready to act when the moment came, and those who jailed him were the captives of their own prejudice. Homo sapiens has seldom been wiser, or half as good.

That is why Obama's fomo sapiens moment on Tuesday was so disappointing. More than any other world leader, he has tried to follow Mandela's example: be patient, take time to reflect, be slow to wrath. Why blow it, on that of all days, for the sake of a moment's distraction?

In his speech at Mandela's memorial service, Obama said: ''Let us search for his largeness of spirit somewhere inside of ourselves.'' Harken to your own words, Mr President: ''Inside our selves.'' Not in our selfies.

London Daily Telegraph