A two-year-old girl has become the youngest member of Mensa, the society strictly for geniuses.

With intelligence far beyond her years, Elise Tan Roberts can name 35 capital cities and identify the three types of triangle. Her IQ is 156 - higher than Carol Vorderman’s, the maths expert and former Countdown host. The average IQ in the population at large is 100.

The toddler, from Edmonton in North London, can already spell her name aloud, read the words “mummy” and “daddy” and recite the alphabet.

Mensa accepts the top two per cent of the population based on IQ and normally only tests children over 10 years old, but the society made an exception and welcomed Elise based on a standard intelligence measure.

The child is in the top 0.2 per cent for her age, according to Professor Joan Freeman, the child psychologist who used the Stanford-Binet Intelligence Scale to test Elise.

John Stevenage, head of Mensa, said he was always delighted to welcome a new member.

“Elise’s parents correctly identified that she is an exceptional child. They now realise they have an interesting challenge on their hands as she grows up.

“We wish them well and look forward to seeing Elise develop in the coming years.”

Elise’s mother Louise, 28, said she realised her daughter was different as soon as she was born.

She took “an unusual” interest in her surroundings, uttered her first word aged just five months and took her first steps at eight-and-a-half months. The little girl was born in London in December 2006 and has heritage in England, Malaysia, China, Nigeria and Sierra Leone.

Mrs Tan Roberts, a part-time accounts manager for Pickford’s removals, said: “She just says things and you have no idea where she got it from.

“I don’t set out to teach her loads of stuff, she just enjoys learning and picks things up. She’s always on the go, she never stops.”

Elise’s father, Edward, 34, a car buyer and motor consultant, said they hoped she continued to learn at a fast pace.

“We don't want to make her have to dumb down and stop learning just to fit in. But she's still my baby. I just want her to be happy and enjoy herself.”

Although members of her family have included doctors and lawyers, none is a member of the high IQ society.

Prof Freeman said the child’s memory was her great gift.

“I was extremely impressed she was able to reel off the capital cities of about 20 countries and state, without hesitation, the phonetic alphabet.

“She has an exceptional memory which doubtless has been, and will continue to be, the source of excellent learning and progress in the educational system. “She is more than very bright and capable - she is gifted.”

Mensa has about 24,000 members in the UK and Ireland - about 900 of whom are aged under 18.

As well as Carol Vorderman, whose IQ is 154, other famous members include Sir Jimmy Savile, DJ and TV presenter and inventor Sir Clive Sinclair.

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