AC 2.1 Flashcards
What do genetic theories suggest about criminality?
Some crime might be attributable to a chromosomal abnormality.
How many chromosomes do humans usually have?
Humans usually have 46 chromosomes.
What determines sex in humans?
Sex is determined by the pattern of a person’s sex chromosomes: XX in a woman, XY in a man.
What is the XYY syndrome?
A condition involving the presence of an extra Y chromosome.
What are XYY men sometimes called?
Super males.
What did Jacob et al. (1965) suggest about XYY men?
They are more aggressive and more inclined to be violent than males with a single Y chromosome.
What is the over-representation of XYY men in prisons?
There are 15 sufferers per 1,000 in prisons and one per 1,000 in the general population.
What is a strength of Jacob’s XXY study?
There has been supporting evidence for the theory.
What did Jacob et al. (1965) find regarding XYY sex chromosomes?
A significant number of men in prison had XYY sex chromosomes instead of the normal XY.
What is a weakness of Jacob’s XXY study?
It focuses too heavily on genetics and ignores the potential influence of the environment.
What evidence refutes Jacob’s XXY study?
Theilgaard (1984) found that aggression was not associated with XYY men.
What do twin studies suggest about criminal behavior?
A heritable trait may increase risk for criminal behavior.
What is the difference between MZ and DZ twins?
MZ twins share 100% of their DNA, while DZ twins share 50%.
What is concordance rate in twin studies?
When both twins share a characteristic.
What is a strength of twin studies?
They are natural experiments, allowing researchers to examine criminal behavior ethically.
What did Christiansen (1977) find in his twin study?
The concordance rate for monozygotic twins was 52%, while for dizygotic twins it was 22%.
What is a weakness of early twin studies?
They were not controlled and lacked validity.
What is another weakness of twin studies?
The samples used are usually quite small, lacking population validity.
Who proposed the physiological theory of born criminals?
Lombroso in 1876.
What did Lombroso claim about criminals?
Criminals were physically different from non-criminals.
What percentage of criminal acts did Lombroso attribute to atavistic characteristics?
40%.
What are some distinctive physical features identified by Lombroso?
Enormous jaws, high cheekbones, handle-shaped ears.
What did Lombroso suggest about different types of criminals?
They had different facial features.
What is a strength of Lombroso’s atavistic theory?
He gave criminology scientific credibility.
