Radioactive dating uses the ratios of isotopes and their specific decay products to determine the ages of rocks, fossils and other substances.
Elements occur naturally in the earth, and they can tell us a lot about our Earth's past.
Within the nucleus, we find neutrons and protons; but for now, let's just focus on the neutrons.
These neutrons can become unstable, and when they do, they release energy and undergo decay. Radioactivity occurs when the nucleus contains an excess amount of neutrons.
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.
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.
During this decay, one substance actually changes into another and radiation is released.
As long ago as 1907, the American chemist Bertram B.
When an atom varies in the number of neutrons, the variation is called an isotope. During radioactivity, the unstable isotope breaks down and changes into a different substance.
A new, more stable isotope, called the decay or daughter product, takes its place.
Perhaps the most widely used evidence for the Theory of Evolution through Natural Selection is the fossil record.
The fossil record may be incomplete and may never fully completed, but there are still many clues to evolution and how it happens within the fossil record.
is a technique used by scientists to learn the ages of biological specimens – for example, wooden archaeological artifacts or ancient human remains – from the distant past.