(March 25, 2014 at 6:19 pm)Thunder Cunt Wrote: When scientists give an estimate that it takes this many million years for a lizard to mutate into a horse, where do they get that number? Someone's head.
Scientists can predict how long ago two species diverged, therefore predicting how long ago the LCA (Last Common Ancestor) lived based on the differences between their genetic code. However, it usually gives a longer ago prediction than the fossil record does. The LCA between humans and chimps differs by around 2 million years depending on whether you use hominid fossils or genetic studies.
Both are backed up by solid science but the methods are still being refined. The predictions will only get better as we learn more.
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