How potassium argon dating works
Atoms are made up of much smaller particles called protons, neutrons, and electrons.Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.Because the cosmic ray bombardment is fairly constant, there’s a near-constant level of carbon-14 to carbon-12 ratio in Earth’s atmosphere.Organisms at the base of the food chain that photosynthesize – for example, plants and algae – use the carbon in Earth’s atmosphere.Anthropologists work with humans their cultures, societies, languages, and ways of life, in addition to their bones and artifacts.Some paleontologists do study the fossil record of humans and their relatives.Thus, as living things take in carbon, they inevitably will take up a small amount of radioactive carbon into their bodies.When these lifeforms die, they stop taking in new carbon.
Most carbon on Earth is not radioactive, but a very small percentage is.They have the same ratio of carbon-14 to carbon-12 as the atmosphere, and this same ratio is then carried up the food chain all the way to apex predators, like sharks.Rachel Wood does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.Here’s an example using the simplest atom, hydrogen. Carbon-14 is an unstable isotope of carbon that will eventually decay at a known rate to become carbon-12.Radiocarbon dating uses isotopes of the element carbon. Cosmic rays – high energy particles from beyond the solar system – bombard Earth’s upper atmosphere continually, in the process creating the unstable carbon-14. Because it’s unstable, carbon-14 will eventually decay back to carbon-12 isotopes.