It turns out our DNA is a kind of molecular clock, keeping time via genetic changes.The identification of fakes and forgeries is a basic issue that has always raised controversy.That gives us a very big clue about how old the Earth is.How do scientists figure out when evolutionary events – like species splitting away from a common ancestor – happened?Willard Libby from the University of Chicago put it to the test.By 1949, he had published a paper in Science showing that he had accurately dated samples with known ages, using radiocarbon dating.
Professor Willard Libby produced the first radiocarbon dates in 1949 and was later awarded the Nobel Prize for his efforts…When we think of the last 50,000 years of prehistory, particularly the “Ice Age”, extinct species such as the woolly mammoth and woolly rhinoceros often spring to mind.
Indeed, the "Secret Of The Southwest" was revealed.
An Isotope Called Carbon-14 But alas, pattern-matching in order to date when a tree was cut isn't always possible.
"Every year the trees in our forests show the swing of Time's pendulum and put down a mark.
They are chronographs, recording clocks, by which the succeeding seasons are set down through definite imprints," he wrote in the pages of National Geographic.
He noticed that trees across the same region, in the same climate, develop rings in the same patterns.