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Mechan intro

This shows how having the darker coloration is advantageous. This also means that a higher proportion of the darker genes will be passed on to the next generation. The process shown is that of Natural selection.

What_is_Natural_Selection?

What is Natural Selection?

Amazing video on natural selection! Very clear information.

Author note: I'm pretty sure no one has done a wiki page on just natural selection yet! Correct me if I'm wrong!

Natural Selection is the process by which evolution occurs. It is a gradual process by which traits pass through a population by inheritance through generations. It operates on heritable traits, or those that are passed on to future generations. Natural selection acts on those traits that help an animal to better succeed either physically or reproductively in its environment (Futuyma, 2009). The theory was first popularized by Charles Darwin after his trip to the Galapagos Islands. 


Futuyma, F.J. 2009. Evolution. 2nd Ed. Chapter 11. Retrieved from http://ncse.com/files/pub/evolution/Evolution--Futuyma--chap11.pdf

Darwin, C.R. (1859). On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [1st edition][]
Freeman, S. & Herron, J. (2007). Evolutionary Analysis 4th Ed. Form and Function, pp 363-396.[]

Video: In the mid 1840's England was burning lots of coal.  They were burning so much coal that the smoke started to blacken trees,  rocks and buildings.  It was the first time that sciencetists noted seeing the black pepper moth, instead of the tradi

Natural_Selection_-_Crash_Course_Biology_14

Natural Selection - Crash Course Biology 14

Loos, Dave (2012). Natural Selection, Crash Course Biology, Retrieved from: http://www.youtube.com/watch?v=aTftyFboC_M

tional white pepper moth.  The environment was selecting for dark colored moths becuase they better blended into the dark backgrounds.  The white moths  were not blending as well and were being eaten more oftern by predators.

Fitness[]

Fitness refers to the ability of individuals to survive to the next generation. If an individual is more "fit", then it is more likely to pass its genes to the next generation because it has better traits to do so. Conversely, if the traits do not allow the individual to pass on its genes, it is less fit. That is where Darwin coined "Survival of the Fittest" In common, everyday language, "fitness" usually describes health, strength, or endurance. Because of this it has lead to many misconceptions in students in understanding survival of the fittest. 


Darwin, C.R. (1859). On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [1st edition][]
Jiméneza, J.I.,Xulvi-Bruneta, R., Campbell, G.W., Turk-MacLeoda, R., Chena, I.A. (2013). Comprehensive experimental fitness landscape and evolutionary network for small RNA. Proceedings of the National Academy of Sciences of the United States of America, 110(37), 14984-14989.[]

Bishop, B.A. & Anderson, C.W. (1990). Student conceptions of natural selection and its role in evolution. Journal of research in science teaching, 27(5), 415-427.

Selection[]

Natural Selection works on heritable traits and can be pressured from different factors to choose specific traits. This can be from different units of selection, from an individual of a species, a gene, cells, or even family groups. Selection for one gene can increase the fitness of that gene. There are different types of selection, such as ecological selection (selection from the environment) and sexual selection, discussed elsewhere in this wiki.


Freeman, S. & Herron, J. (2007). Evolutionary Analysis 4th Ed. Form and Function, pp 363-396.[]
McEwen, J.R., Vamosi, J.C., Rogers, S.M. (2013). Natural Selection and Neutral Evolution Jointly Drive Population Divergence between Alpine and Lowland Ecotypes of the Allopolyploid Plant Anemone multifida (Ranunculaceae). PLoS One, 8(7), 1-10.[]

VISTA: Steps of Natural Selection[]

There are five basic steps in the natural selection process, as first posited by Darwin. The Americam Museum of Natural History (AMNH) has devised an acronym to help peope understand and remember these steps: VISTA

V - Variation  -- There is natural variation among the members of the population.

I - Ineritance -- These traits and characteristics are passed down from parent to offspring.

S - Selection -- (note: you could also use Struggle for Survival here...) Since more individuals are born than can survive, there is an ongoing struggle, or competition, for limted resources. Those individuals possessing characteristics that give them even a slight advantage will be more likely to survive to reproduce, thus passing the genes for those advantageous characteristics along to future generations.

T -- Time -- over time, lots and lots of time and mutliple generations, these characteristics become more prevalent in the population

A -- Adaptation -- after a long enough time has passed, the population will exhibit adaptations that suit the organims particulary well for its environment.

The AMNH website about natural selection can be accessed here: http://www.amnh.org/exhibitions/past-exhibitions/darwin/evolution-today/how-does-natural-selection-work

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