What is livor mortis?

Livor mortis refers to the noticeable reddish discoloration of the skin that occurs after death due to the pooling of blood in the lower parts of the body. This phenomenon happens as the heart ceases to pump blood and gravity causes the blood to settle in areas where the body is in contact with a surface, leading to the characteristic purple or reddish marks. The presence of livor mortis helps forensic scientists determine not only the position of the body after death but also can provide additional information regarding the time of death, as it typically develops within a couple of hours and becomes fixed after several hours.

The other options address different aspects of post-mortem changes. The pale color of skin is not specific to livor mortis, as other factors can cause paleness. While livor mortis can be an indicator of time of death, it is more specifically the observable condition of the skin rather than a direct measure of time. Muscle stiffness, known as rigor mortis, is a separate post-mortem change characterized by stiffness in the muscles due to biochemical changes in the body after death.