Life span
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. 

The lifespan of humanoid species was known to vary from less than a decade to as long as several millennia. Some non-corporeal species were known to have lifespans exceeding several millennia. 

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 Capellan flower, native of Capella IV, had a life span of only a few hours. ()

The swarming moths of Gonal IV had a life span of only twenty hours. Jay Gordon Graas analyzed the insects' life span as part of his primary school science fair project in 2368. () 

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. ()

The Ocampa had a lifespan of only nine years. () Suspiria developed technology that helped extend the Ocampa life span; ' father, for example, lived to be twenty years of age. ()

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. ()

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. () 

Trill could live at least one hundred years. ()

During the 24th century, Bajorans could live to at least one hundred years. Els Renora was one such individual to live to the century mark. ()

Ferengi might live over a century. ()
{{bginfo|This is based on Ishka claiming that after her ears raised, her lobes were firmer than they had been in over a century. The statement might be taken to imply that they could live at least another hundred years after the end of their prime. Legends of the Ferengi by Ira Steven Behr and Robert Hewitt Wolfe stated Ferengi could live up to three hundred years.}}

Antarans of the 22nd century were thought to generally live at least sixty additional years after reaching adulthood. ()

One Drayan was ninety six years old when she reached the natural end of her life. ()

The average Human life span had gradually increased during their history. The average life spans during the 22nd century was about one hundred years. () This average age was still roughly the same during the 2250, but had risen to 120 by the mid-24th century.  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. (; ) Leonard McCoy had by 2364 reached the age of 137. ()

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. () Another exception were Human Augments, who had life spans twice as long as those of regular 22nd century Humans. ()

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. ()

Vulcans were known to have life spans of two hundred years, which was considered to be exceptionally long by Federation standards. (; ) Sarek of  lived to be 203 years of age. () However, at some point in their history, the average lifespan of Vulcans was only 40. ().  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. () 

Krenim could live at least two hundred years. ()

At least one Kriosian, Briam, reached two hundred years, which was considered old. ()

The Talosians had life spans that were many times that of a Human's. ()

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. 

Changelings had an expected life span of at least several centuries. (

The Axanar had an average life span of 400 years. () Tarquin's species also lived for at least four hundred years. Tarquin remarked that few species have lifespans as long as his. ()

El-Aurians life spans were at least several hundred years. () Guinan was also on Earth during the late 19th century, making her at least 490 years old. (). Her father had reached 700 years by 2369. () The El-Aurian Doctor Tolian Soran was reported to be "over three hundred years old" in his biographical information.()

The Redjac entity had an extremely long lifespan, at least 379 years. It was speculated by Spock to be virtually immortal. ()

While the lifespan of regular Horta is unknown, the Mother Horta lived for 50,000 years. )

Cheron natives were also known to be extremely long lived. Bele claimed to have pursued Lokai for more than 50,000 years ()

Bevvox, a bioplasmic organism who lived alone for a few millennia, was said to be somewhat sensitive about his age. ()

Another type of bioplasmic organism, the Telepathic pitcher plant, was estimated to be at least 200,000 years old. ()

A Magnetic organism was found to have survived on a derelict ship for 300,000,000 years. ()

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. ()

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 (). 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, later known as a hyperaccelerated aging disease. (; ) In 2365, a freak Thelusian flu antibody reaction caused a similarly rapid aging. ()

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. ()

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. () After Quark was diagnosed with Dorek Syndrome, he was told that he had only about six days to live. () 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. ()

More elementary, lifestyle conditions could also drastically reduce life expectancy. The life expectancy for prisoners sent to Rura Penthe was six months to a year. ()

Extension of lifespanFor methods of Rejuvenation (as opposed to just prolonging life), see Rejuvenation.''

Likewise, several methods have also been found to slow the aging process, such as the life prolongation project, albeit with negative side effects. (). 

According to Jadzia Dax, regularly eating steamed Azna would add years to your life. ()

On the Dinaali homeworld some people were given Cytoglobin injections to prevent arterial aging and thus increase life expectancy by 40%. ()

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. (). 

The Son'a also applied intriguing methods of enhancing their life spans. ()

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. () 

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. ()

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. (; ; )

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. ()

Suspiria helped the Ocampa develop a technology to extend their lifespan.  and his father lived to 14 and 20 respectively. ()

External links 
 
 
Physiology
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