Resolving the IQ paradox: heterosis as a cause of the Flynn effect and other trends.

  title={Resolving the IQ paradox: heterosis as a cause of the Flynn effect and other trends.},
  author={Michael A. Mingroni},
  journal={Psychological review},
  volume={114 3},
IQ test scores have risen steadily across the industrialized world ever since such tests were first widely administered, a phenomenon known as the Flynn effect. Although the effect was documented more than 2 decades ago, there is currently no generally agreed-on explanation for it. The author argues that the phenomenon heterosis represents the most likely cause. Heterosis, often referred to as hybrid vigor, is a genetic effect that results from matings between members of genetically distinct… 

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