When cosmic rays enter the atmosphere, they cause "scatter radiation," which consists of little particles called neutrons.A moving neutron is a high-energy particle which performs an interesting task.Anything that was once alive or that was produced by a living thing can be dated by using the radiocarbon method of dating.
Carbon is present in proteins, fats and carbohydrates – the three basic foods.
The plant, animal and human will each have about the same ratio of C-14 to C-12 as does the air.
The next question is: Where did the air get its C-14?
Some of the scientists who date by C-14 claim these are only small fluctuations and would have no overall effect.
But if there can be small fluctuations in the amount of the C-14 produced in the atmosphere day by day, then there could have been greater fluctuations in Earth's history. What might such changes in the atmosphere mean for dating studies?