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Examine one evolutionary explanation of behavior

The theory of evolution, suggested by Charles Darwin, is based on the assumption that living organisms face environmental challenges. Organisms that adapt the best have a greater chance of passing on their genes to the next generations.

Organisms with specific genetic traits that enhance survival are said to be naturally selected. Natural selection is a crucial evolutionary process in Darwin’s theory.

One evolutionary explanation of behavior: disgust in pregnant women

  • Nausea and loss of appetite during pregnancy may have been evolved as a way to protect the mother and the fetus against diseases which could threaten the fetus. Disgust has evolved as a food-rejection response to prevent contamination and the spread of illness.
  • The theory under investigation is whether disgust has evolved to compensate for the mother and the baby’s vulnerability to disease during the first few months of pregnancy.

Study to use: Fessler et al (2005)



Evaluation of evolutionary explanations

  • It is difficult to test evolutionary theories and not much is known about the life of early humans.
  • Evolutionary explanations tend to focus on biological factors and underestimate cultural influences.