Photographer and doctor David Teplica discusses his art and his science

The fertility pioneer and BBC presenter Lord Robert Winston opened the show and told BBC News Online that artistic explorations could add to the debate as well as scientific ones.

"Identical twins are the most perfect clones, more perfect than could be created artificially. But the interesting thing about them is their differences, not their similarities," he said.

Refusion (the Dworkin twins) by Dr David Teplica

Lord Winston said clones would be even more different: "They are brought up in different uterine environments, on different time scales and have different influences.

"I'm not advocating cloning, but I don't find it threatening," he added.

Together and apart

The photographs in "Take Two: Identical Twins in Focus" were taken by Dr David Teplica, a plastic surgeon and photographer from Chicago, USA and went on show at the Wellcome Trust's Two10 Gallery in London on Thursday.

"I'm fascinated by the idea that twins feel the need to become individuals, and that society forces them to develop separate personalities," said Dr Teplica. "This is the exact opposite of what should be happening - they have the same gene, anatomy and minds."

Kiss/Bite (The dworkin twins) by Dr David Teplica

"Recent research shows that twins raised separately are more alike, suggesting that environment has a negative impact on how we express our genetic potential," he said.

Denna Jones, curator at the Wellcome Trust, said: "Nature makes its own clones but deliberate laboratory cloning has become a topical social concern. Identical twins offer not only a unique scientific opportunity to investigate inherited and non-inherited traits and their contribution to the personality, but also provide a down-to-earth perspective on the cloning debate."

Unique models

As a photographer, Dr Teplica believes using identical twins as models is a unique opportunity: "They are very comfortable with each other - if one wants to bite the others jaw, the other is happy to oblige."

Dr Teplica also carries out scientific research on twins into similarities in secondary skin characteristics, such as exactly where a wrinkle appears or which eye-brow hair turns grey first.

He has also amassed an unprecedented archive of 8,000 clinical images over the last 10 years and found extraordinary similarities between identical twins: "It's amazing to see things like two 12-year old identical twin girls whose acne has erupted in exactly the same spot on the nose."

Dr Teplica believes his obsession with twins may come from his own birth - he was one of twins, but his sibling miscarried in the fourth month of pregnancy.

Take Two: Identical Twins in Focus is on show at the Wellcome Trust's Two10 Gallery, London from 22 July to 24 September 1999. Admission is free.

All photographs copyright of Dr David Teplica, St Joseph Hospital, Chicago, USA