Darwin's 4 Postulates

Emily Fernandez

The Four Attributes of Nature

  • Variation among individuals
  • Variation is heritable
  • Overprodution of young is the rule
  • Non-random survival and reproduction: those with the most favorable traits will survive, passing on these traits to the next generation.

Things to Remember

  • Natural selection will inevitably occur if the four postulates are true and species will change.
  • Natural selection affects individuals overtime
  • Natural selection creates new things: range of variation can transcend and new things can be created modifying the old
  • Cannot produce perfect organisms

Evolution by natural selection may result in increased complexity

Variation

Problems with the Theory

  • What is the variation of source?
  • Why wouldn't natural selection stop when variation is exhausted?
  • How is variation passed on from generation to generation?

Explaining Variation

  • Controversial because variation and its inheritance can not be adequately explained in terms of existing knowledge
  • blending ineritance: deplete population of organisms of all variation
  • phenotypic variation may indicate blending of sorts, the inherited material-namely the genes-remains discrete

Bibliography

Ch1. Adaptation by Natural Selection. (2016). Wwnorton.com. Retrieved 6 April 2016, from http://www.wwnorton.com/college/anthro/bioanth/ch1/chap1.htm


BBC - GCSE Bitesize: Darwin's theory of evolution. (2016). Bbc.co.uk. Retrieved 6 April 2016, from http://www.bbc.co.uk/schools/gcsebitesize/science/21c_pre_2011/evolution/theoryevolutionrev2.shtml


Ch 3. Darwinian Natural Selection. (2016).Faculty.buffalostate.edu. Retrieved 6 April 2016, from http://faculty.buffalostate.edu/penaloj/bio405/outline3.html