Algor mortis.

Investigators of homicides use various techniques to estimate the length of time since death, or the postmortem interval (PMI). It is likely that before the techniques employed by modern investigators gained wide acceptance, early hunters and gatherers distinguished the same stages of decomposition following death. Such stages include the fresh, bloat, active, and advanced decay stages versus the stage at which remains become dry or skeletonized. However, the indicators that modern forensic investigators consider classic for suggesting PMI are those of algor mortis (cooling of the body), rigor mortis (stiffening of the body), and livor mortis (discoloration of the body from gravitational blood seepage).