Big Dave, you may want to read the work done by David Lack in the 1940s with respect to the Galapagos finches. His work was what "finally" put beyond doubt evolution. Darwins's work was much more conceptual than conclusive.

Incidentally Lack was a staunch atheist, but after his work on proving evolution he became very much open to the idea of a God. Also, two of his children subsequently became preists.

With regards uranium isotope aging of rocks and carbon dating of artefacts, it is not the total quantity that is important but concentrations/ratios. With uranium, the ratio of U-235 to U-238 can be used to determine how old the rocks are. As they decay at different rates they will have existed in different ratios in the past. As we know what the ratios of the isotopes is at the moment rocks are created, then we know when it was created by extrapolating back the ratios of uranium at various times.

With carbon dating its the ratio of C-14 to C-12, in a similar fashion, the ratio of C-12 to C-14 is known at the time of death, and you back extrapolate decay rates. In this instance C-12 has an almost infinite half-life.

Incidentally Lack was a staunch atheist, but after his work on proving evolution he became very much open to the idea of a God. Also, two of his children subsequently became preists.

With regards uranium isotope aging of rocks and carbon dating of artefacts, it is not the total quantity that is important but concentrations/ratios. With uranium, the ratio of U-235 to U-238 can be used to determine how old the rocks are. As they decay at different rates they will have existed in different ratios in the past. As we know what the ratios of the isotopes is at the moment rocks are created, then we know when it was created by extrapolating back the ratios of uranium at various times.

With carbon dating its the ratio of C-14 to C-12, in a similar fashion, the ratio of C-12 to C-14 is known at the time of death, and you back extrapolate decay rates. In this instance C-12 has an almost infinite half-life.

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