What Is Death and Why Is Death? An Evolutionary Biological Perspective

In the context of human clinical medicine, we define death when the heart has stopped, or the brain has ceased to show any function even if the rest of the body is maintained with the help of artificial mechanical ventilation. Death is a point on a biological continuum, and the definition of death is legal, not medical. When death is declared, not all cells are dead, but, given enough time, all the cells will die. Cell death occurs when that cell loses the ability to metabolize and self-generate its own energy, even in the most favorable environment. In the context of biology, we can summarize death very differently, focusing on three basic aspects of biology. First is the DNA. This directs the creation of structure. DNA has variously been called a genetic code, a biological program, a source of information, or an evolutionary strategy. Second is natural selection. Here, of all the various DNA options, some survive better and start dominating the population and increase their frequency in the overall biological population. Third, these selected genes maintain structural and functional complexity by resisting entropy. When a biological individual dies, all the individual molecules continue to exist and go on to circulate in the environment. What has died is not the actual matter or structure. What has died is the ability of that individual to maintain complexity and resist entropy.