 By the 1960s, she had turned her attention to the origins of antibody specificity.Jim Allison, a colleague from Berkeley, said "Bunny analyzed polyclonal antibodies directed against two different haptens, and on the basis of exquisitely careful amino acid composition analyses, convincingly showed that these antibodies had different amino acid compositions and therefore must differ in their amino acid sequence.These data had a profound effect on theories of antibody formation and how antibody specificity was generated.