The 7.1-kilogram rock has been identified as the mineralized fecal remains left behind when a tyrannosaurus...relieved itself in a river delta 65 million years ago....'It is the birth of the science of [comparative] poopology,' Stanford University paleontologist and co-author Gregory Erickson said of the find's significance.
—Stephen Strauss, "Birth of a science: comparative poopology," The Globe and Mail, June 18, 1998