Named in honour of George C. Williams, the Williams Revolution is the phrase sometimes used to characterise the paradigm shift which is asserted to have occurred in theoretical biology in the mid-1960s.
Although population genetics was largely the basis for the modern evolutionary synthesis and described in terms of genes, verbal arguments were nearly always couched in terms of "survival of the species", i.e. group selection. This was replaced by using a gene-centric view of evolution, epitomised by kin selection. Theorisation showed that group selection was severely limited in its strength.