What came first, the chicken or the egg? Scientists in Britain think it was probably the chicken, after using new computer technology to try and crack the age-old riddle.

Researchers at the Universities of Sheffield and Warwick, in northern and central England, say the secret lies in the eggshell - specifically the vital role played by a chicken protein in forming it.

Scientists already knew that the protein, vocledidin-17 (OC-17), plays a part in eggshell formation, but the new technology allowed the team to demonstrate exactly how the protein makes it happen.

In a computer simulation, the OC-17 protein acted as a catalyst to kickstart the formation of crystals that make up an eggshell by clamping itself on to calcium carbonate particles. The OC-17 protein then dropped off when the crystal nucleus was large enough to grow on its own, freeing up the protein to start the process again.

Eggshells are created when this happens many times over within a short period of time.

"Understanding how chickens make eggshells is fascinating in itself but can also give clues towards designing new materials and processes," said Professor John Harding from Sheffield University, one of the authors of the research.

"Nature has found innovative solutions that work for all kinds of problems in materials science and technology - we can learn a lot from them," he added.