Death is the termination of all biological functions that sustain a living organism. Phenomena which commonly bring about death include biological aging (), predation, malnutrition, disease, suicide, homicide, starvation, dehydration, and accidents or trauma resulting in terminal injury. Bodies of living organisms begin to decompose shortly after death. Death has commonly been considered a sad or unpleasant occasion, due to the termination of social and familial bonds with the deceased or affection for the being that has died. Other concerns include fear of death, necrophobia, anxiety, sorrow, grief, emotional pain, depression, sympathy, compassion, solitude, or saudade.