It's the age-old question that has puzzled the finest minds for thousands of years - which came first: The chicken or the egg?

Now, scientists claim to have finally discovered the answer to the conundrum - it's the chicken which came first. A team from University of Sheffield and University of Warwick has found that a protein called ovocleidin (OC-17) is crucial in the formation of eggshells.

It is produced in the pregnant hen's ovaries so the correct reply to the egg riddle must be that the chicken came first, the experts say. However, the research does not come up with how the protein-producing chicken existed in the first place, the Daily Express reported on Wednesday.

The team of researchers used a hi-tech computer, called HECToR, to look at the molecular structure of a shell. They discovered that OC-17 acts as a catalyst, kickstarting the conversion of calcium carbonate in the chicken's body into calcite crystals.

It is these that make up the hard shell that houses the yolk and its protective fluids while the chick develops.

Lead scientist Colin Freeman of Sheffield University said: "It had long been suspected that the egg came first but now we have the scientific proof that shows that in fact the chicken came first."

The scientists now hope the breakthrough could be used in industry to help develop new materials.

Courtesy: PTI & TOI