Radiometric dating for dummies
Darwin had finally gotten the luxury of time he had craved.
The dates that radioactive clocks have put on evolutionary history are astonishing.
The primordial cloud of dust that came to form the Earth contained unstable atoms, known as radioactive isotopes.
The difference between 12C, 13C and 14C is the number of neutrons each carbon atom contains, 12c holds 6 protons and 6 neutrons, 13C contains 6 protons and 7 neutrons, and lastly 14C has 6 protons and 8 neutrons. What are some other radiometric decay systems (besides carbon-14) that are useful for determining the ages of evens in Earth’s history?
Darwin had argued that the Earth was immensely old which gave his gradual process of evolution plenty of time to unfold.
The great physicist Lord Kelvin had countered that the planet was actually relatively young perhaps 20 million years old.
Mammals, which for 150 million years had been small, rodent-sized creatures, rapidly evolved to massive proportions in the wake of the Cretaceous-Tertiary extinction 65 million years ago.
Geological timekeeping continues to be a lively science, with new methods emerging all the time.