Radioactive carbon dating origin of life sex dating in texico new mexico
The primordial cloud of dust that came to form the Earth contained unstable atoms, known as radioactive isotopes.
Since its birth, these isotopes have been breaking down and releasing energy that adds heat to the planet's interior.
Life is well over 3.5 billion years old, and until about 600 million years ago, the planet was dominated by microbes.
Radioactive clocks have shown that evolution can change its pace the Cambrian Explosion of about 535 million years ago saw the relatively rapid emergence of many major lineages of animals in just a few million years.
Darwin had finally gotten the luxury of time he had craved.
The dates that radioactive clocks have put on evolutionary history are astonishing.
Geological timekeeping continues to be a lively science, with new methods emerging all the time.While some physicists used these discoveries for applications ranging from nuclear weapons to nuclear medicine, others applied them to understanding the natural world.The sun was once thought to burn like a coal fire, but physicists showed that it actually generates energy by slamming atoms together and creating new elements.Radioactivity also gave the history of life an absolute calendar.By measuring the atoms produced by these breakdowns inside rocks, physicists were able to estimate their ages (right).
What I want to do in this video is kind of introduce you to the idea of, one, how carbon-14 comes about, and how it gets into all living things. They can also be alpha particles, which is the same thing as a helium nucleus. And they're going to come in, and they're going to bump into things in our atmosphere, and they're actually going to form neutrons. And we'll show a neutron with a lowercase n, and a 1 for its mass number. And what's interesting about this is this is constantly being formed in our atmosphere, not in huge quantities, but in reasonable quantities. Because as soon as you die and you get buried under the ground, there's no way for the carbon-14 to become part of your tissue anymore because you're not eating anything with new carbon-14.