Scientists know that carbon 14 decays (imagine it getting lost, or rotting away) at about 1/2 every 5,000 years. That means that if you had 100 pieces of carbon 14 in you and we waited for 5,000 years . . . . . . . half of it would now be gone - leaving 50 pieces. After 10,000 years half of that would be gone - leaving 25 pieces.
This process continues on and on, of course after a few thousand years it gets tough to count how much there is, so many scientists say it probably would only work for 50,000 years.
How Accurate is Carbon Dating?
While carbon dating is fascinating, it uses several "assumptions." An assumption is something you decide before even starting to look at evidence. I "assume" that everyone reading this page understands english. That is why this page is only in the english language. But If I were to assume that everyone reading this page had green hair and purple shoes on - I would probably be making a big mistake!
Here are some "assumptions" carbon dating techniques use:
1) There has always been as much carbon 14 in the atmosphere as there is today.
2) Carbon 14 has always decayed at the same speed.
3) All living things absorb the same amount of carbon as the atmosphere has in it
