Natural, Relaxed, and Artificial Selection <br />Hasan Mahmud<br />
Natural Selection <br />Is the basis of the other types of selection<br />Competition Variation<br />Heriatble Differen...
Relaxed Selection <br />Is a selective phenomena that occurs when selective pressures are either elimatedor dramatically r...
Examples of Relaxed Selection <br />When selective pressures are reduced or eliminated they can be biotic or abiotic<br />...
Modern Medicine <br />Modern Medicine<br />Elimination of Many diseases that used to be lethal<br />Compensation for Chron...
Other Examples <br />Malaria resistance<br />Without the pressure of possible infection there is no heterozygous advantage...
Problems with Relaxed Selection <br />Many of the problems with relaxed selection only come into play when those pressures...
Artificial Selection <br />Usually through intention human involvement the selection of non-essential traits in a populati...
Misconception of Artificial Selection <br />Artificial Selection does and cannot create new traits<br />Uses recessive tra...
Problems with Artificial Selection <br />While some examples of artificial selection are not intentional <br />Initial dom...
Connections <br />Artificial, Relaxed, and Natural Selection are not separate and different forces<br />Each is just a sub...
Works Cited <br />http://images.google.com/imghp?gbv=2&um=1&hl=en&btnG=Search+Images<br />1 Bryant, Edwin H. "Fitness Decl...
of 13

Natural, Relaxed, and Artificial Selection

Published on: Mar 3, 2016
Source: www.slideshare.net


Transcripts - Natural, Relaxed, and Artificial Selection

  • 1. Natural, Relaxed, and Artificial Selection <br />Hasan Mahmud<br />
  • 2. Natural Selection <br />Is the basis of the other types of selection<br />Competition Variation<br />Heriatble Difference in survival<br />Relaxed and Artificial Selection are simply natural selection under different <br />Each of the two change different parameters and <br />
  • 3. Relaxed Selection <br />Is a selective phenomena that occurs when selective pressures are either elimatedor dramatically reduced <br />Are many new cases as society becomes more and more complex<br />
  • 4. Examples of Relaxed Selection <br />When selective pressures are reduced or eliminated they can be biotic or abiotic<br />Biotic examples <br />Predation elimination <br />Elimination of pathogen<br />Abiotic examples<br />Changes in light and temperature and water<br />Changes soil and mineral composition <br />
  • 5. Modern Medicine <br />Modern Medicine<br />Elimination of Many diseases that used to be lethal<br />Compensation for Chronic and Genetic Diseases<br />Helps with common health problems<br />Sight problems<br />Hearing problems<br />
  • 6. Other Examples <br />Malaria resistance<br />Without the pressure of possible infection there is no heterozygous advantage<br />Galapagos <br />Without the presence of predators and the abundance of food many animals in the Galapagos have become much larger than their main land counterparts <br />
  • 7. Problems with Relaxed Selection <br />Many of the problems with relaxed selection only come into play when those pressures are re-introduced<br />While some times the organism has come up with new way to deal with the pressures other times can be very costly to the pouplation<br />
  • 8. Artificial Selection <br />Usually through intention human involvement the selection of non-essential traits in a population<br />Many times the means through which selection is done is harmful to the population<br />Artificial selection is done for two purposes<br />To increase production such as milk, eggs, meat<br />Enhancement of desired traits e.x dogs horses <br />
  • 9. Misconception of Artificial Selection <br />Artificial Selection does and cannot create new traits<br />Uses recessive traits or enhances existing traits to unusual expression <br />Many of the artificially created species can still breed with ancestral species <br />
  • 10.
  • 11. Problems with Artificial Selection <br />While some examples of artificial selection are not intentional <br />Initial domestication of Animals<br />Initial enhancement of crops<br />Many examples of Artificial Selection are done through in breeding <br />Purebred dogs<br />Race horses <br />
  • 12. Connections <br />Artificial, Relaxed, and Natural Selection are not separate and different forces<br />Each is just a subset of the larger evolutionary force <br />Artificial selection is taken to the extreme where there is a desired goal<br />Relaxed selection is the absence of pressure and the evolutionary pathways that forms <br />
  • 13. Works Cited <br />http://images.google.com/imghp?gbv=2&um=1&hl=en&btnG=Search+Images<br />1 Bryant, Edwin H. "Fitness Decline under Relaxed Selection in Captive Populations." Conservation Biology 13 (2001): 665-69. <br />2 "Evolution and Natural Selection." Evolution and Natural Selection. 10 Oct. 2008. Universtiy of Michigan. 5 Nov. 2008 <http://www.globalchange.umich.edu/globalchange1/current/lectures/selection/selection.html>. <br />3 Foster, Susan A., and John A. Endler. "Effects of Relaxed Selection Evolutionary Behavior." Geographic Variation in Behavior. <br />4 Gayle, Lisa. "Genetic Disorders." Encyclopedia of Childhood and Adolescence 42 (1998).<br />5 Guyon, Isabelle. "An introduction to variable and feature selection." The Journal of Machine Learning Research 3 (2003): 1157-182. <br />6 Innan, Hideki. "Pattern of polymorphism after strong artificial selection in a domestication event." Biological Science 109 (2004): 106667-0672. <br />7 "Malaria and the Red Cell." 02 Apr. 2002. Information center for sickle and thalessis Disease. 28 Nov. 2008 <http://sickle.bwh.harvard.edu/index.html>.<br />8 Robertson, A. "A Theory of Limits in Artifical Selection." Proceedings of the Royal Society of London. Series B, Biological Sciences 153 (2000): 234-49. <br />

Related Documents