Microbes signal deceased's time of death

Microbes might help crime scene investigators pinpoint a person’s time of death.

In a step toward using bacteria and other microbes as forensic evidence, Jessica Metcalf of the University of Colorado Boulder and colleagues tracked how microbial populations changed as mouse carcasses decomposed. By determining the type and abundance of certain bacteria on the body, the researchers could determine when the mice died to within about three days, the team reports September 23 in a paper to be published in eLife. Populations of microscopic worms, called nematodes, also bloomed at predictable times as the mice decayed.

It makes sense to use microbes to investigate when a person or animal died, says Jeffery Tomberlin, a decomposition ecologist at Texas A&M University in College Station. “Microbes play a huge role in how we live.”