My colleague Joseph Stromberg recently visited the Freeman Ranch body farm near San Marcos, Texas, where scientists study how bodies decompose on land. This knowledge turns out to be incredibly useful for forensics scientists and criminal investigators.
But what about bodies found in the water? Scientists haven't looked into this as much, although they have recently been making new headway. Criminologists Gail Anderson and Lynne Bell, of Simon Fraser University in Canada, published a paper this week describing results from experiments in which they watched pigs (common stand-ins for people) decompose at the bottom of the sea. Remote sensors record factors such as the temperature, salinity, and pressure of the water while cameras track the progress.
The videos from their ongoing sea pig projects, like the one above, are both disgusting and fascinating. They've discovered that sea lice, crabs, and red crustaceans known as squat lobsters all play a major role in helping decomposition in that area. By the end, there's nothing but a pile of bones.
In the researchers' latest paper, they note that two pig corpses in higher-oxygen waters were quickly eaten by crustaceans, whereas a corpse in low-oxygen waters sat there for 92 days until the oxygen rose and the crabs came. Oxygen levels can vary with the seasons, which could help give an indication of time of death for bodies. The researchers' work could also help determine what happened to a body before it entered the water versus after.
This sort of research has already proved valuable in some cases. "After several human feet clad in athletic shoes started washing up on Vancouver's shores in 2007, Anderson quashed speculation that a serial killer was lopping them off," Brooke Borel wrote in a 2013 Popular Science story. "The cause of death still isn't clear, but we now know that sea life snipped away enough tissue that the feet fell off on their own."
There are more pigs being studied right now, and you can watch them on a live feed if you want. And here's a compilation of clips from the recent paper that LiveScience put together:
Further reading: The science of human decay: Inside the world's largest body farm