A life span, life expectancy, or life cycle was the maximum or average length of time a lifeform, material, or object was projected or capable of living or lasting. Having an effectively unlimited lifespan was referred to as immortality.
Generally speaking, a life cycle was marked by the process of aging, beginning at birth and ending with death – either prematurely or naturally. It might be divided into states, such as childhood, adolescence, adulthood, and old age.
Comparative life spans
The Lyssarian Desert Larvae, after becoming a mimetic simbiot, exactly replicated the life cycle of the species it was mimicking at a rapidly accelerated rate. On average, the simbiot was born, grew old, and died in approximately fifteen days. (ENT: "Similitude")
The Ocampa had a lifespan of only nine years. (VOY: "Caretaker", "Death Wish", "Before and After", "Fury") Suspiria developed technology that helped extend the Ocampa life span; Tanis' father, for example, lived to be twenty years of age. (VOY: "Cold Fire")
Following an autopsy of a Xindi-Insectoid, Doctor Phlox projected that this species of Xindi only had the lifespan of about twelve Earth years. He then suggested that the Insectoid he conducted his autopsy on was about ten years of age, and was likely one of the elder members of its crew. (ENT: "Hatchery")
Most Jem'Hadar died young in battle; as such, it was rare for them to live past fifteen years of age. Few ever lived to the age of twenty, and those who do were awarded the title "Honored Elders." As of the Dominion War, No Jem'Hadar had ever lived to the age of 30. (DS9: "To the Death")
The average Human life span had gradually increased during their history. The average life spans during the 22nd century was about one hundred years. (ENT: "Observer Effect") This average age was still roughly the same during the 2250, but had risen to 120 by the mid-24th century. (citation needed • edit) However, at some point in history the average lifespan for Humans was only 35, and by 1999 it had become higher than a millennium earlier. (ENT: "Similitude"; VOY: "11:59") Leonard McCoy had by 2364 reached the age of 137. (TNG: "Encounter at Farpoint")
Despite the normal limit on Human age, at least one Human, Flint, lived for six thousand years for unknown reasons which were somehow dependent on the Earth's environment. (TOS: "Requiem for Methuselah") Another exception were Human Augments, who had life spans twice as long as those of regular 22nd century Humans. (ENT: "Borderland")
Klingons were capable of living well over a century in age. Individuals such as Kang, Koloth, Kor, and Arne Darvin lived well over one hundred years. (DS9: "Blood Oath", "Trials and Tribble-ations", "Once More Unto the Breach")
Vulcans were known to have life spans of two hundred years, which was considered to be exceptionally long by Federation standards. (ENT: "Broken Bow"; TNG: "Unification I") Sarek of Vulcan lived to be 203 years of age. (TNG: "Sarek") However, at some point in their history, the average lifespan of Vulcans was only 40. (ENT: "Similitude"). Trip Tucker scoffed at the idea of Mestral, a Vulcan who lived on Earth beginning in the 20th century, remained there for the rest of his life, which could have been longer than 150 years. Tucker was especially averse to the idea that a Vulcan could live the rest of his lifespan on Earth, unnoticed, from the 1950s through a period of time that included the terms of 30 United States Presidents. (ENT: "Carbon Creek")
Trill symbionts were capable of living at least over 550 years. Trill hosts however tended to live significantly shorter than the symbiont, resulting in a symbiont usually occupying many different hosts during its lifetime.
The Axanar had an average life span of 400 years. (ENT: "Fight or Flight") Tarquin's species also lived for at least four hundred years. Tarquin remarked that few species have lifespans as long as his. (ENT: "Exile")
El-Aurians life spans were at least several hundred years. (TNG: "Q Who") Guinan was also on Earth during the late 19th century, making her at least 490 years old. (TNG: "Time's Arrow", "Time's Arrow, Part II"). Her father had reached 700 years by 2369. (TNG: "Rascals") The El-Aurian Doctor Tolian Soran was reported to be "over three hundred years old" in his biographical information.(Star Trek Generations)
Borg life spans were the natural life span of whatever species the drone was originally assimilated from, except when the individual was assimilated as a child, in which case maturation was accelerated. (VOY: "Survival Instinct", "Collective")
Denobulan life spans were never specified, Phlox once told Archer that they live "a long time". Additionally Phlox had to treat an patient whose species Denobulans had fought many times in the past, the Antarans (ENT: "The Breach"). Phlox stated that his grandmother had lived through the last war, which was earlier stated as having occurred three hundred years previously.
Reduction of lifespan
Several natural and unnatural conditions have been encountered that are known to hasten the aging process. For example, radiation has been known to accelerate aging, dramatically. (TOS: "The Deadly Years") In 2365, a freak Thelusian flu antibody reaction caused a similarly rapid aging. (TNG: "Unnatural Selection")
Delta radiation, emitted by mirror universe warp five engines, was also very harmful. It was said that, for each year a Human spent working next to a warp core, he lost a decade of his life. (ENT: "In a Mirror, Darkly")
For slow and fatal diseases, a revised life expectancy was also usually given. As part of a (possibly false) diagnosis of Tuvan Syndrome, Koval was expected to live another 20 or 25 years. (DS9: "Inter Arma Enim Silent Leges") After Quark was diagnosed with Dorek Syndrome, he was told that he had only about six days to live. (DS9: "Body Parts") More humorously, Julian Bashir claimed that, due to the extreme old age associated with winning, the life expectancy for a Carrington Award winner was five to ten years. (DS9: "Prophet Motive")
Extension of lifespan
- For methods of Rejuvenation (as opposed to just prolonging life), see Rejuvenation.
Doctor Elias Giger claimed that his cellular regeneration and entertainment chamber could effectively grant immortality, but this claim was considered dubious by the Federation scientific establishment. (DS9: "In the Cards").
The Kobliad, a dying race due to cellular degeneration, were able to nonetheless prolong their lifespan using deuridium to stabilize their cell structure. A Kobliad named Rao Vantika went further and tried to prolong his death by experimenting with rejuvenation drugs, cryogenics, and organ transplants. (DS9: "The Passenger")
Bathar of Hodos, a salesman traveling the Delta Quadrant in the 24th century, claimed to have a formula that stopped the aging process. In reality it was only a tripolymer enzyme though. (VOY: "Memorial")
Apart from actual changes in the pace of aging, The use of technologies like cryonics, stasis chambers and even transporters have allowed individuals to temporary suspend their lives and therefore live into eras their normal lifespans would not have normally allowed them to live. (TOS: "Space Seed"; TNG: "The Neutral Zone", "The Emissary", "Relics"; VOY: "The 37's")
There also existed spatial anomalies, such as the Nexus, which trapped people within alternate temporal realities thereby continuing their lifespan beyond normal measure and under special circumstance could allow them to occupy a later time-space than their genetics would normally allow. (Star Trek Generations)