Carbon dating is the most famous form of “radiometric dating”. The reason carbon dating works is that the fresh carbon-14 gets mixed in with the rest of the carbon in the atmosphere and, since it’s chemically identical to regular carbon, gets worked into whatever is presently absorbing atmospheric carbon. In particular: plants, things that eat plants, things that eat things that eat plants, and breatharians. Not being made of carbon, we can’t carbon date them. : carbon dating.