Current Biology. That paper stated:
In laboratory-based experimental evolution of novel phenotypes and the human domestication of crops,
the majority of the mutations that lead to adaptation
are loss-of-function mutations
that impair or eliminate the function of genes rather than gain-of-function mutations that increase or qualitatively alter the function of proteins.
Murray's paper vindicated Behe's thesis which also argued tha
t "random mutation and natural selection are in fact fiercely devolutionary." That is since "mutation easily breaks or degrades genes, which, counterintuitively, can sometimes help an organism to survive, so the damaged genes are hastily spread by natural selection." (
Darwin Devolves, p. 10) He continues: