When a rock is on the surface, it builds up these isotopes.
When it is buried or deposited in a cave, the isotopes decay at known rates.
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These two are no longer married, as a meter of fact, Jerri has remarried, but what about Coach Painter?
If a strong isochron line forms, it increases the confidence that the samples on the line meet the criteria to be good candidates for accurate dating.
Gibbon joined Granger in his work on the Sterkfontein samples in 2010 and was a key player in the research.Previous dates ranged from 2 million to 4 million years old, with an estimate of 3 million years old preferred by paleontologists familiar with the site, said Darryl Granger, a professor of earth, atmospheric and planetary sciences at Purdue, who in collaboration with Ryan Gibbon, a former postdoctoral researcher, led the team and performed the dating.Purdue University professors Darryl Granger (left) and Marc Caffee stand in front of the gas-filled magnet detector in the Purdue Rare Isotope Measurement Laboratory.The new date places Little Foot as an older relative of Lucy, a famous Australopithecus skeleton dated at 3.2 million years old that was found in Ethiopia.It is thought that Australopithecus is an evolutionary ancestor to humans that lived between 2 million and 4 million years ago.
The detector was used to date the Little Foot skeleton.