Biological immortality refers to a stable or decreasing rate of mortality from cellular senescence as a function of chronological age. Various unicellular and multicellular species may achieve this state either throughout their existence or after living long enough. A biologically immortal living thing can still die from means other than senescence, such as through injury or disease.
This definition of immortality has been challenged in the new Handbook of the Biology of Aging, because the increase in rate of mortality as a function of chronological age may be negligible at extremely old ages, an idea referred to as the late-life mortality plateau. The rate of mortality may cease to increase in old age, but in most cases that rate is typically very high. As a hypothetical example, there is only a 50% chance of a human surviving another year at age 110 or greater.
Read more about Biological Immortality: Cell Lines, Organisms, Political Struggle For Immortalism and Immortality, Life Extensionists
Famous quotes containing the words biological and/or immortality:
“Man’s biological weakness is the condition of human culture.”
—Erich Fromm (1900–1980)
“The moment the doctrine of the immortality is separately taught, man is already fallen. In the flowing of love, in the adoration of humility, there is no question of continuance. No inspired man ever asks this question, or condescends to these evidences. For the soul is true to itself, and the man in whom it is shed abroad cannot wander from the present, which is infinite, to a future which would be finite.”
—Ralph Waldo Emerson (1803–1882)