Fossil dating method

05 Nov

Later, this date was confirmed by two other dating methods (paleomagnetism and fission tracks), and was widely accepted.

At the basis of the theory of neo-Darwinian evolution lie two basic assumptions: that changes in morphologies are induced by random mutations on the genome, and that these changes in the morphology of plant or animal make the life form either more or less successful in the competition to survive.For example, in the 1940s the U-Th-He method was used.But these tests quickly became notoriously unreliable, as they indicated so many different "ages" for the same rock layer.If history is anything to go by, then the answer is no.The process generally used to date a fossil is circuitous and subject to differing interpretations.So Curtis and others redated the KBS tuff using selected pumice and feldspar samples, and obtained an age of 1.82 million years.This new date agreed with the appearance of the new skull.Where igneous rocks are absent, a fossil's "age" is determined by comparing the fossils of one location to those of another, and then comparing those comparisons to charts in books with age assignments provided on the pages.But in standard studies, no age assignment is ever accepted unless it conforms to the "millions of years" doctrine of evolutionary earth history.So, in the 1950s, K-Ar and Rb-Sr methods became popular among geologists.However, Woodmorappe quoted a radiodating textbook as saying, "The Rb-Sr whole-rock method was widely used as a dating tool for igneous crystallization during the 1960's and 1970's, but lost credibility during the 1980's as evidence of whole-rock open-system behaviour mounted." "Open-system behaviour" is a term invoked when the same technique delivers inconsistent age assignments for the same rock.