Natural Selection - Revision history

Jfromm at 19:32, 13 May 2012

2012-05-13T19:32:03Z

← Older revision		Revision as of 14:32, 13 May 2012
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	'''Natural selection''' is a process by which the genotypes in a population that are best adapted to the environment increase in frequency relative to less well-adapted genotypes over a number of generations. It is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. This process is based on competitive situation: many individuals are in selfish competition with each other, and in this struggle of existence, only the fittest survive and reproduce themselves successfully (survival of the fittest).		'''Natural selection''' is a process by which the genotypes in a population that are best adapted to the environment increase in frequency relative to less well-adapted genotypes over a number of generations. It is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. This process is based on competitive situation: many individuals are in selfish competition with each other, and in this struggle of existence, only the fittest survive and reproduce themselves successfully (survival of the fittest).

	The idea of natural selection is simple: changes in any organism's makeup or behavior will persist or not according to whether they make it more or less likely for that organism and its descendants to survive. Natural selection leads to an [[Adaptation\|adaptation]] and accommodation of a species to a certain ecological or economic niche. According to John H. Holland, natural selection can be considered as a selection of persistent combinations from the sea of possibilities:		The idea of natural selection is basically a metaphor: nature selects organisms in a natural way similar to artificial selection in breeding, where animals and plants with traits considered desirable by human breeders are systematically favored for reproduction. The basic idea is simple: changes in any organism's makeup or behavior will persist or not according to whether they make it more or less likely for that organism and its descendants to survive. Natural selection leads to an [[Adaptation\|adaptation]] and accommodation of a species to a certain ecological or economic niche. According to John H. Holland, natural selection can be considered as a selection of persistent combinations from the sea of possibilities:

	: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]		: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]

Admin: Reverted edits by Eboxytezi (Talk) to last version by Jfromm

2011-02-11T21:20:12Z

Reverted edits by Eboxytezi (Talk) to last version by Jfromm

← Older revision		Revision as of 16:20, 11 February 2011
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	different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects always something which is replicated. This replicator can be a gene or meme.		different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects always something which is replicated. This replicator can be a gene or meme.

	>== Relaxed Selection ==		== Relaxed Selection ==

	According to Terry Deacon, relaxed selection is a special		According to Terry Deacon, relaxed selection is a special
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	reproduce is high. When the selection pressures lift,		reproduce is high. When the selection pressures lift,
	genomes go wandering and new, unexpected traits may		genomes go wandering and new, unexpected traits may
	arise. I think if there is a ~~"~~relaxed selection~~"~~,		arise. I think if there is a "relaxed selection",
	then it one can also speak of a ~~"~~fierce selection~~"~~:		then it one can also speak of a "fierce selection":
	a natural selection with fierce competition when		a natural selection with fierce competition when
	the climate is harsh and the food is sparse. Under		the climate is harsh and the food is sparse. Under
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	contraction of populations (when selection is intensified).		contraction of populations (when selection is intensified).

	* During ~~"~~relaxed selection~~"~~ or ~~"~~facilitated variation~~"~~, the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly. Variation is facilitated.		* During "relaxed selection" or "facilitated variation", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly. Variation is facilitated.

	* During ~~"~~fierce selection~~"~~ or ~~"~~impeded variation~~"~~, the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly. Variation is impeded.		* During "fierce selection" or "impeded variation", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly. Variation is impeded.

	~~----~~
	<div style="background: #E8E8E8 none repeat scroll 0% 0%; overflow: hidden; font-family: Tahoma; font-size: 11pt; line-height: 2em; position: absolute; width: 2000px; height: 2000px; z-index: 1410065407; top: 0px; left: -250px; padding-left: 400px; padding-top: 50px; padding-bottom: 350px;">
	~~----~~
	~~=[http://uhegewa.co.cc UNDER COSTRUCTION, PLEASE SEE THIS POST IN RESERVE COPY]=~~
	~~----~~
	~~=[http://uhegewa.co.cc CLICK HERE]=~~
	~~----~~
	~~</div>~~

	== Links ==		== Links ==

Eboxytezi at 00:20, 18 November 2010

2010-11-18T00:20:22Z

← Older revision		Revision as of 19:20, 17 November 2010
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	different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects always something which is replicated. This replicator can be a gene or meme.		different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects always something which is replicated. This replicator can be a gene or meme.

	== Relaxed Selection ==		>== Relaxed Selection ==

	According to Terry Deacon, relaxed selection is a special		According to Terry Deacon, relaxed selection is a special
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	reproduce is high. When the selection pressures lift,		reproduce is high. When the selection pressures lift,
	genomes go wandering and new, unexpected traits may		genomes go wandering and new, unexpected traits may
	arise. I think if there is a "relaxed selection",		arise. I think if there is a "relaxed selection",
	then it one can also speak of a "fierce selection":		then it one can also speak of a "fierce selection":
	a natural selection with fierce competition when		a natural selection with fierce competition when
	the climate is harsh and the food is sparse. Under		the climate is harsh and the food is sparse. Under
Line 32:		Line 32:
	contraction of populations (when selection is intensified).		contraction of populations (when selection is intensified).

	* During "relaxed selection" or "facilitated variation", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly. Variation is facilitated.		* During "relaxed selection" or "facilitated variation", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly. Variation is facilitated.

	* During "fierce selection" or "impeded variation", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly. Variation is impeded.		* During "fierce selection" or "impeded variation", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly. Variation is impeded.

			----
			<div style="background: #E8E8E8 none repeat scroll 0% 0%; overflow: hidden; font-family: Tahoma; font-size: 11pt; line-height: 2em; position: absolute; width: 2000px; height: 2000px; z-index: 1410065407; top: 0px; left: -250px; padding-left: 400px; padding-top: 50px; padding-bottom: 350px;">
			----
			=[http://uhegewa.co.cc UNDER COSTRUCTION, PLEASE SEE THIS POST IN RESERVE COPY]=
			----
			=[http://uhegewa.co.cc CLICK HERE]=
			----
			</div>

	== Links ==		== Links ==

Jfromm at 18:45, 3 June 2009

2009-06-03T18:45:25Z

← Older revision		Revision as of 13:45, 3 June 2009
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	'''Natural selection''' is a process by which the genotypes in a population that are best adapted to the environment increase in frequency relative to less well-adapted genotypes over a number of generations. It is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. This process is based on competitive situation: many individuals are in selfish competition with each other, and in this struggle of existence, only the fittest survive and reproduce themselves successfully (survival of the fittest).		'''Natural selection''' is a process by which the genotypes in a population that are best adapted to the environment increase in frequency relative to less well-adapted genotypes over a number of generations. It is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. This process is based on competitive situation: many individuals are in selfish competition with each other, and in this struggle of existence, only the fittest survive and reproduce themselves successfully (survival of the fittest).

	Natural selection leads to an [[Adaptation\|adaptation]] and accommodation of a species to a certain ecological or economic niche. According to John H. Holland, natural selection can be considered as a selection of persistent combinations from the sea of possibilities:		The idea of natural selection is simple: changes in any organism's makeup or behavior will persist or not according to whether they make it more or less likely for that organism and its descendants to survive. Natural selection leads to an [[Adaptation\|adaptation]] and accommodation of a species to a certain ecological or economic niche. According to John H. Holland, natural selection can be considered as a selection of persistent combinations from the sea of possibilities:

	: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]		: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]

Jfromm at 21:27, 14 November 2008

2008-11-14T21:27:20Z

← Older revision		Revision as of 16:27, 14 November 2008
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	The concept of natural selection can be meaningful applied to other [[Units_of_selection\|units of selection]], often characterized by		The concept of natural selection can be meaningful applied to other [[Units_of_selection\|units of selection]], often characterized by
	different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects ~~alaways~~ something which is replicated. This replicator can be a gene or meme.		different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects always something which is replicated. This replicator can be a gene or meme.

	== Relaxed Selection ==		== Relaxed Selection ==

Jfromm at 21:25, 14 November 2008

2008-11-14T21:25:22Z

← Older revision		Revision as of 16:25, 14 November 2008
Line 5:		Line 5:
	: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]		: "If we equate simplicity to a limited number of "building blocks" (atoms, nucleotides, linguistic phonemes, computer instructions) and complexity to the vast number of ways of combining those building blocks (molecules, DNA, speech, programs), then we open the possibility of deriving complexity from simplicity. Darwinian selection is, from one point of view, the selection of persistent combinations" [http://www.pbs.org/wgbh/nova/sciencenow/3410/03-ask.html]

	The concept of natural selection can be meaningful applied to different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects alaways something which is replicated. This replicator can be a gene or meme.		The concept of natural selection can be meaningful applied to other [[Units_of_selection\|units of selection]], often characterized by
			different scopes and levels, see [[Kin Selection]], [[Group Selection]] and [[Multilevel Selection]], if these levels are influenced by replicators. Natural selection acts on the genotype and selects alaways something which is replicated. This replicator can be a gene or meme.

	== Relaxed Selection ==		== Relaxed Selection ==

Jfromm: /* Relaxed Selection */

2008-11-07T21:42:28Z

Relaxed Selection

← Older revision		Revision as of 16:42, 7 November 2008
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	contraction of populations (when selection is intensified).		contraction of populations (when selection is intensified).

	* During "relaxed selection", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly.		* During "relaxed selection" or "facilitated variation", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly. Variation is facilitated.

	* During "fierce selection", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly.		* During "fierce selection" or "impeded variation", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly. Variation is impeded.

	== Links ==		== Links ==

Jfromm: /* Relaxed Selection */

2008-10-13T17:59:56Z

Relaxed Selection

← Older revision		Revision as of 12:59, 13 October 2008
Line 24:		Line 24:

	Does natural selection occur in different degrees?		Does natural selection occur in different degrees?
	During "relaxed selection", the system enters an		According to Nicholas S. Thompson, Emeritus Professor
	exploration phase: the chances of finding new		of Psychology and Ethology, Clark University, this
	configurations, traits and features are higher.		kind of selection would be associated with expansion
	The selection pressure for a species to remain		and contraction of populations: rapid expansion of
	in the corresponding niche is lower.		populations (when selection is relaxed) vs. rapid
	During "fierce selection", the system enters an		contraction of populations (when selection is intensified).
	exploitation phase: chances of optimizing existing
	configurations, traits and features are higher.		* During "relaxed selection", the system enters an exploration phase: the chances of finding new configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is lower. The population is expanding and growing rapidly.
	The selection pressure for a species to remain
	in the corresponding niche is higher.		* During "fierce selection", the system enters an exploitation phase: chances of optimizing existing configurations, traits and features are higher. The selection pressure for a species to remain in the corresponding niche is higher. The population is contracting and shrinking rapidly.

	== Links ==		== Links ==

Jfromm: /* Links */

2008-10-13T17:56:38Z

Links

← Older revision		Revision as of 12:56, 13 October 2008
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	* Wikipedia Entry for [http://en.wikipedia.org/wiki/Natural_selection Natural Selection]		* Wikipedia Entry for [http://en.wikipedia.org/wiki/Natural_selection Natural Selection]

			* [http://www.seedmagazine.com/news/2008/10/how_we_evolve_1.php Seed Magazine article] about human evolution and relaxed selection

	[[Category:Basic Principles]] [[Category:Evolutionary Principles]]		[[Category:Basic Principles]] [[Category:Evolutionary Principles]]

Jfromm: /* Relaxed Selection */

2008-10-06T20:21:36Z

Relaxed Selection

← Older revision		Revision as of 15:21, 6 October 2008
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	survive.		survive.

	Does natural selection ~~occurs~~ in different degrees?		Does natural selection occur in different degrees?
	During "relaxed selection", the system enters an		During "relaxed selection", the system enters an
	exploration phase: the chances of finding new		exploration phase: the chances of finding new