Stiff: The Curious Lives of Human Cadavers explores the history and ethical dilemmas of postmortem human bodies being put to use by science. Each chapter delves into individual cases of cadavers being used to a specific end. In chapter 4, "Dead Man Driving," author Mary Roach pays a visit to Wayne State University to observe some rather forceful tests conducted on a cadaver known as UM 006. A group of scientists at the university wants to measure the impact of certain car crashes on the human body, namely how much impact a human shoulder can withstand before it is seriously injured. These are known as impact tolerance studies. The author uses this case study to elaborate the role cadavers play in our vehicular safety standards. Anatomical accuracy is extremely important when measuring the effects of a car accident on the human body. It logically follows that a human cadaver provides the most accurate test results, as a dummy or another cadaver (such as an ape) simply does not have the same composition. Current safety standards for our windshields, airbags, and steering wheels are a direct result of tests conducted with human cadavers.