 In the March 2005 issue of "Science", Dr. Mary Higby Schweitzer and her team announced the discovery of flexible material resembling actual soft tissue inside a 68-million-year-old "Tyrannosaurus rex" leg bone of specimen MOR 1125 from the Hell Creek Formation in Montana.The seven collagen types obtained from the bone fragments, compared to collagen data from living birds (specifically, a chicken), suggest that older theropods and birds are closely related.The soft tissue allowed a molecular comparison of cellular anatomy and protein sequencing of collagen tissue published in 2007, both of which indicated that "T. rex" and birds are more closely related to each other than either is to "Alligator".