Tony:I am not claiming that the changes to the vocal tract are simple or trivial. Far from it! The thrust of the claim was the first part of the statement: "This claim ONLY works if we assume that we are descended from chimps" > > http://genome.cshlp.org/content/15/12/1746.full-I have a book, "Not a Chimp", by Jeremy Taylor, Oxford Press, 2009, which describes the DNA of humans and chimps at about 79% (from memory) the same.