Audiences see it time and time again in movies and television shows; the lumbering zombie walks up to one of the characters and is given a decent whack with a bat or stabbed through the head, rendering the zombie “dead”. But is it really as easy to crack or puncture the skull as it can be made to look on the screen? In fact there is a difference in the force needed to crack a zombie skull depending on whether it is a “fresh zombie” or an “old zombie”. After an interview with Forensic Archaeologist Darryl Ricketts at Indiana University South Bend, a lot of insight was given. The main factor that plays into how easy it is to crack a zombie skull is how long it has been decomposing.
Blunt Force Trauma
According to Professor Ricketts, the calvaria which is the skull cap and base, are the parts we need to focus on because the skull has two layers of fat and bone with a layer of dipole you want to penetrate. Now this all changes after the body starts to decompose because in a living person or “fresh zombie” the brain has a layer of tissue, cartilage and skin, being referred to as “wet” making it more flexible and resistant to blunt trauma, needing about 400 to 1800 pounds of blunt force to crack the skull. In an older zombie in where decomposition has long set in, these protective layers decay and the bone loses moisture, being referred to as “dry”. A dry skull is less flexible therefore it needs less blunt force to destroy it, taking as little as only 1/10 of what is needed for a “wet” skull. (D. Ricketts, personal communication, October 12, 2015).
Sharp Force Trauma
In the case of puncturing the skull referred to as “sharp force trauma” the amount of force needed would be much lower depending on whether the same amount of force or energy is being using as blunt force. Since only a small surface area is being attacked less force is needed for both “dry” and “wet” skulls. This means that in fact it is entirely as easy to puncture a skull as it looks on television, be it a knife or screwdriver. In fact Professor Ricketts made the point that, “there are many studies that show carnivores such as wolves and coyotes easily puncturing skeletal material when scavenging remains. Indeed, one of the things we look for is penetration of canine teeth”. (D. Ricketts, personal communication, October 12, 2015).