Similar findings were made in Iraq, showing that people lived there 25,000 years ago.This is just to mention a few of the age determinations which throw light on the prehistory of mankind.Traces of the first human habitations in these regions were dated to about 10,000 years ago.
But nevertheless, this ratio can be determined, for carbon-14 is a radioactive isotope and manifests itself by its radiation.
Westgren, Chairman of the Nobel Committee for Chemistry of the Royal Swedish Academy of Sciences Your Majesty, Your Royal Highnesses, Ladies and Gentlemen.
The Royal Swedish Academy of Sciences this year has decided to award with the Nobel Prize for Chemistry a scientific feat which is less a direct improvement of our material living standards, but more a means of widening and deepening our knowledge in different scientific fields.
If it is assumed that the intensity of the cosmic radiation has been constant during the last few tens of thousands of years, then the average lifetime of carbon-14 - which is approximately 8,000 years - should be sufficiently long to allow for the formation of a stationary state in the concentration of this isotope not only with reference to the atmosphere, but also to the hydrosphere and biosphere as well.
Active and non-active carbon dioxide are dissolved in a contant ratio in the water of the seas and lakes where they are converted into carbonate and bicarbonate, and they are assimilated by trees and plants, and finally also by the animals, which ultimately live on plants.