genetic Theories (biological) Flashcards
(8 cards)
What is Jacob’s XYY theory?
When a male receives an extra Y chromosome it is called super male syndrome.
These males are usually tall, well built and of low intelligence. Jacob also claimed they were much more violent and aggressive.
What study took place that backs Jacob’s XYY theory?
A study took place at psychiatric hospitals where a higher than average number of males with super male syndrome were imprisoned, most of these males had violent convictions and were immature and unstable.
A strength of Jacob’s XYY theory?
A link between genetics and violence was found, supporting genetic theories for criminality.
A weakness of Jacob’s XYY theory?
Stereotypes around tall well built men began to form, causing problems for people with those characteristics but without the syndrome.
What is the twin studies?
Crime runs in families due to relatives sharing many of the same genes.
The identical twins were used to back up this theory as they have the same genes.
What did christiansens study of 3586 twin pairs show?
52% of the pairs both had criminal convictions
22% of non identical twins both had convictions
Strengths of twin studies?
twin genes are identical, supporting genetic theories for criminality.
weakness of twin studies?
other factors are more important as only just over 50% of the twin pairs both had criminal convictions.
