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In 1907, Bertram Boltwood published an article describing a novel, radiometric method for determining the age of minerals - a method he used to date a rock sample at more than 2 billion years: to search the CAS databases for additional information about radiometric dating and evolution.
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The rules are the same in all cases; the assumptions are different for each method.
Radiometric dating not only supports the geologic "evolution" of the Grand Canyon, it validates a central tenet in a much different theory of evolution - a theory introduced by Charles Robert Darwin in his 1859 publication, An important criticism of Darwin's theory of evolution was its requirement for "an almost infinite number of generations", when evidence at the time suggested earth was less than 100 million years old.
Nearly 50 years after Darwin published , research on radioactive elements in rocks provided the first reliable evidence that the earth was old enough to accommodate the evolution of complex organisms.
Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years.
Mountains have been built and eroded, continents and oceans have moved great distances, and the Earth has fluctuated from being extremely cold and almost completely covered with ice to being very warm and ice-free.
A fossil can be studied to determine what kind of organism it represents, how the organism lived, and how it was preserved.
However, by itself a fossil has little meaning unless it is placed within some context.
Professor Willard Libby produced the first radiocarbon dates in 1949 and was later awarded the Nobel Prize for his efforts.
Radiocarbon dating works by comparing the three different isotopes of carbon.
These changes typically occur so slowly that they are barely detectable over the span of a human life, yet even at this instant, the Earth's surface is moving and changing.