Saturday, October 23, 2010
The Forensics of Horror Part III: Zombies
There is an excellent article in the very theme we have been focusing on this month over at Cracked. The 7 Scientific Reasons a Zombie Apocalypse Would Fail. Although the article doesn't entirely focus on forensics it is a very science based approach to discussing a zombie apocalypse. They don't tie their discussion to forensics, but indeed their article does have those ties.
Maggot development is often used to date a decomposing body. The Tennessee Body Farm has extensive information on timing bodies through maggots. The maggot lifespan is very clearly documented and by knowing what stage of life the maggots are in, one can date the age of the decomposing body. Flies typically lay eggs on a dead body within 30 hours. I don't know about you, but that in itself would make me want to be found quick!
Bloat and dessication are affected greatly by temperature and can be used as well on the timing of death. Cold is a little trickier. We're all just meat when it comes down to it. If you leave a steak in the freezer for a very long period of time your meat will be ruined for eating, true, but it won't be decomposed. The same is true for a body frozen shortly after death. Stories of finding frozen "cavemen" have shown examples where bodies have been preserved by freezing for millenia. This obviously can make it tricky to know how long the body has been there. At that point missing person reports would be helpful and for very long periods of time dates (such as on a drivers license) on any identification would be helpful and even the style of clothes can aid in timing the death.
Here's the problem. You have an enormous pool of blood made up of multiple victims. Where do you sample from? Liquids mix together. The blood of the victims won't stay in their distinct spots which means the DNA sample you have will be completed contaminated. Large pool of blood with multiple victims? You might as well not have any blood at all! A sample can be contaminated to the point of ruin. We've all heard stories of DNA evidence being thrown out of court because of contamination and that's in the real world.
DNA evidence in a zombie apocalypse? Forget we ever had the capability.