It is called 'radio'-carbon, because it is 'radioactive'.This means that its atomic structure is not stable and there is an uneasy relationship between the particles in the nucleus of the atom itself.Because carbon is very common on Earth, there are alot of different types of material which can be dated by scientists.
The job of a radiocarbon laboratory is to measure the remaining amounts of radiocarbon in a carbon sample.
This is very difficult and requires a lot of careful work to produce reliable dates.
During the period of a plant's life, the plant is taking in carbon dioxide through photosynthesis, which is how the plant makes energy and grows.
Animals eat plants, and some eat other animals in the food chain.
Rasmus Nyerup's quote reminds us of the tremendous scientific advances which have taken place in the 20th century.