A team of British researchers say they’ve worked out how eggshells are produced. It appears to confirm that the chicken did indeed come first.
The solution lies in a chicken protein named ovocledidin-17 (OC-17) which is found in the hard layer of the shell.
A team led by Mark Rodger and David Quigley have published a paper in chemistry journal Angewandte Chemie detailing their work with metadynamics, a computing tool which analyzes and simulates the way molecules interact.
They spent around 1,000 hours on HECToR (High End Computing Terascale Resources), a British supercomputer available for academic and industrial research.
Using the tool they were able to show that two lops on the OC-17 protein clamp onto calcium carbonate particles and prompt the calcium carbonate to form crystallites which then continue to grow into crystal. Once the crystals can grow on their own, the protein drops away and latches on to other calcium carbonate particles and starts the process over again. This works so efficiently that there are enough crystals to form an eggshell within a day.
The Toronto Star has some interesting background on previous attempts to solve the chicken and egg conundrum, my favorite being the researcher who mailed one of each from Massachusetts to Manhattan. The chicken came first.