Copyright © Philip M. Parker, INSEAD. Terms of Use.
Definition: Lifespan |
LifespanNoun1. The period during which something is functional (as between birth and death); "the battery had a short life"; "he lived a long and happy life". Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
Date "lifespan" was first used in popular English literature: sometime before 1985. (references) |
(From Wikipedia, the free Encyclopedia)
simple:LifeLife is a primarily biological concept with no simple definition.
- Alternate meanings: Conway's Game of Life, Hasbro's Game of Life, personal life, Life magazine, Life imprisonment
Attempts to define the concept of life
The conventional definition
An entity is usually considered to be alive if it exhibits the following phenomena at least once during its existence:
Controversially, according to this definition,
- Growth
- Metabolism, consuming, transforming and storing energy; growing by absorbing and reorganizing mass; excreting waste
- Motion, either moving itself, or having internal motion
- Reproduction, the ability to create roughly exact copies of itself
- Stimulus response, the ability to measure properties of its surrounding environment, and act on certain conditions
- fire is alive. (This could be remedied by adding the requirement of locality, where there is an obvious feature that delineates the spatial extension of the living being (such as a cell membrane).)
- a mule is not alive. (It cannot reproduce and produce a mule.)
- virii are not alive. (They cannot grow or evince behavior.)
Other definitions
Other definitions include:
- Lynn Margulis's definition of life as an autopoietic (self-producing), water based, lipid-protein bound, carbon metabolic, nucleic acid replicated, protein readout system
- "a system of inferior negative feedbacks subordinated to a superior positive feedback" (J. theor Biol. 2001)
- "functional organization for sustaining self and kind, involving active use of energy and information replication (respectively)" (Human Knowledge: Foundations and Limits, which classifies about twenty-five categories of replicating or self-sustaining phenomena)
- Tom Kinch's definition of life as a highly organized auto-cannibalizing system naturally emerging from conditions common on planetary bodies, and consisting of a population of replicators capable of mutation, around each set of which a homeostatic metabolizing organism, which actively helps reproduce and/or protect the replicator(s), has evolved
- Stuart Kauffman's definition of life as an autonomous agent or autonomous agents capable of reproducing itself or themselves, and of completing at least one thermodynamic work cycle
Descent with modification: a "useful" characteristic
A useful characteristic upon which to base a definition of life is that of descent with modification: the ability of a life form to produce offspring that are like it, but that also have the possibility of random variations. This characteristic alone is sufficient to allow evolution, assuming the variations in the offspring allow for differential survivability. The study of this form of heritability is called genetics, and in all known life forms, with the exception of prions, the genetic material is primarily DNA, or the related molecule, RNA. Another exception might be the software code of certain forms of virii and programs created through genetic programming, but whether computer programs can be alive even by this definition is still a matter of some contention.
Exceptions to the common definiton
Note that many individual organisms are incapable of reproduction and yet are still generally considered to be "alive;" see mules and ants for examples. However, these exceptions can be accounted for by applying the definition of life on the level of entire species or of individual genes. (For example, see kin selection for information about one way by which non-reproducing individuals can still enhance the spread of their genes and the survival of their species.)
Virii reproduce, flames grow, some software programs mutate and evolve, future software programs will probably evince (even high-order) behavior, machines move, and proto-life, consisting of metabolizing cells without reproduction apparatus, can have existed. Still, some would not call these entities alive. Generally, all six characteristics are required for a population to be considered alive.
The possibility of extraterrestrial life
As of 2003, Earth is the only planet in the universe known by humans to support life. The question of whether life exists elsewhere in the universe remains an open question, although the probability that Earth is the only location in the universe, or even the galaxy, that harbors life, is extremely low. There have been a number of false alarms of life elsewhere in the universe, but none of these apparent discoveries have so far survived scientific scrutiny.
Currently, the closest that scientists have come to finding extraterrestrial life is fossil evidence of possible bacterial life on Mars. There also may be simple life forms on Jupiter's moons.
Other facts
All life on Earth is based on the chemistry of carbon compounds. Some assert that this must be the case for all possible forms of life throughout the universe; others describe this position as 'carbon chauvinism'.
The most successful animal of the earth, in terms of biomass, is the Antarctic krill, Euphausia superba, with a biomass of probably over 500 million tonnes.
Lifespan is the length of life in each species. Death is the termination of life in a living system, or in part thereof. Some people think that life was created by God or gods.
Related articles
- Meaning of life
- Vitalism
- Materialism
- Artificial life
- Value of life
- Afterlife
Reference
- Kauffman, Stuart. The Adjacent Possible: A Talk with Stuart Kauffman. Retrieved Nov. 30, 2003 from [http://www.edge.org/3rd_culture/kauffman03/kauffman_index.html]" class="external">[1]
External link
- "The Adjacent Possible: A Talk with Stuart Kauffman"
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Life."
Synonyms: LifespanSynonyms: life (n), lifetime (n). (additional references) |
Crosswords: Lifespan |
| Specialty definitions using "lifespan": Endocrine disruptor ♦ Stellar evolution ♦ USG Unix. (references) |
| Domain | Usage | |
Screenplays | The problem with you mortals is the limited lifespan. Rush, rush, rush, rush, rush less than a century to get things done (So Weird; writing credit: John Mandel) | |
Movie/TV Titles | Lifespan (1974) | |
Source: compiled by the editor from various references; see credits. | ||
| Domain | Title |
Books |
|
Source: compiled by the editor from various references; see credits. | |
| Subject | Topic | Quote |
Health | On the average, individuals with CF have a lifespan of approximately 30 years. (references) | |
Most patients with lupus have a normal lifespan with periodic doctor visits and treatments with various drugs. (references) | ||
Better treatment methods developed over the past 20 years have increased the average lifespan of CF patients to nearly 30 years. (references) | ||
Business | Products like forks and spades have a much longer lifespan, and replacement purchases are much more infrequent. (references) | |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
| Speaker | Phrase(s) |
Jay McGraw | Well, we're living longer. You know our lifespan is longer and so, percentage-wise, we're getting married about the same time. |
Source: compiled by the editor from various references; see credits. | |
| "Lifespan" is generally used as a noun (singular) -- approximately 100.00% of the time. "Lifespan" is used about 3,694 times out of a sample of 100 million words spoken or written in English. Its rank is based on over 700,000 words used in the English language. Some parts-of-speech are not covered due to the samples used by the British National Corpus. (note: percents less than one-hundredth of one percent have been omitted) |
| Parts of Speech | Percent | Usage per 100 Million Words | Rank in English |
| Noun (singular) | 100% | 3,694 | 2,627 |
Source: compiled by the editor from several corpora; see credits.
Expression using "lifespan": useful lifespan. Additional references. | |
| Hyphenated Usage | |
Beginning with "lifespan": lifespan-able, lifespan-manual-pack, lifespan-pi, Lifespan-pmr, lifespan-to-lifespan. | |
Ending with "lifespan": lifespan-to-lifespan. | |
| Source: compiled by the editor from various references; see credits. | |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Language | Translations for "lifespan"; alternative meanings/domain in parentheses. | |
Albanian | jetëgjatësi (durability, life, longevity, span). (various references) | |
French | vie utile (life, life span), durée de vie des trépans (lifespan of bits). (various references) | |
German | lebenserwartung (length of life, life expectancy). (various references) | |
Greek | όριο ζωής, μέγιστη διάρκεια ζωής. (various references) | |
Italian | durata della vita (age, life, life span, lifetime). (various references) | |
Korean | 수명. (various references) | |
Manx | bea [f] (animation, disquietude, life, vital as statistics), bea (animation, disquietude, life, vital). (various references) | |
Pig Latin | ifespanlay.(various references) | |
Spanish | durabilidad de la barrena (lifespan of bits). (various references) | |
Swedish | livslängd (life, life span). (various references) | |
| Source: compiled by the editor from various translation references. | ||
Misspellings | |
"Lifespan" is suggested in spellcheckers for the following: lifepan, lifeplan, Liffespan. (additional references) | |
| Source: compiled by the editor, based on several corpora (additional references). | |
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "a-e-f-i-l-n-p-s" | |
-1 letter: alpines, finales, pineals, spaniel, splenia. | |
-2 letters: aliens, alines, alpine, elains, elfins, espial, falsie, finale, finals, flanes, lapins, lianes, lipase, panels, penial, pensil, pilafs, pineal, plains, planes, saline, silane, spinal, spinel, spline. | |
-3 letters: aisle, alefs, alien, alifs, aline, anile, anils, anise, aspen, elain, elans, elfin, fails, false, fanes, files, final, fines, flans, flaps, fleas. | |
| Words containing the letters "a-e-f-i-l-n-p-s" | |
+3 letters: flippancies, halfpennies, lifemanship, painfullest, painfulness. | |
+4 letters: lifemanships, professional, saponifiable. | |
+5 letters: flavoproteins, fluphenazines, painfulnesses, passionflower, professionals, unspecifiable. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
| 1. Definition 2. Synonyms 3. Crosswords 4. Usage: Modern | 5. Usage: Commercial 6. Quotations: Non-fiction 7. Quotations: Spoken 8. Usage Frequency | 9. Expressions 10. Expressions: Internet 11. Translations: Modern 12. Derivations | 13. Anagrams 14. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
