2.1 - Biological Theories of Crime Flashcards
what are biological theories of crime?
- the basic idea
the theory that criminals are biologically different to non-criminals - these differences cause them to commit crime
what are the 4 biological explanations for criminality?
Physiological theories
Genetic theories
Brain injuries and disorders
Biochemical
name the 2 theories of physiological theories & what they studied
Lombroso - Atavism
Sheldon - Somatotypes
what did lombroso suggest criminals could be defined by?
destinctive physical features eg. large jaw, high cheekbones, curly hair, protuding nose
characteristics eg. tattoes & insensitivity to pain
what did lombroso describe criminals as?
atavistic - presocial and unable to control impulses
what is atavism?
a throwback to an earlier, more primitive stage of evolution.
what did sheldon suggest criminals could be identified with?
‘somatotypes’ - bodytypes
name the 3 somatotypes of sheldons theory
ectomorphs
mesomorphs
endomorphs
what are ectomorphs?
thin, fragile people who lack muscle and fat
self-conscious personality and emotionally restrained
what are endomorphs?
rounded, soft people who have fat and lack muscle
sociable and relaxed personality
what are mesomorphs?
muscular and hard bodied - little fat and more muscle
outgoing personality & enjoy physical activity
which somatotype does sheldon suggest are more likely to commit crime and why?
mesomorphs - more attracted to the risk-taking and physical physique is an important asset to crime
what are the 3 genetic theories of crime?
XYY theory
adoption studies
twin studies
what’s the name for twins who are non identical?
dyzgotic twins - share 50% of the same DNA
whats the name of twins who are identical?
monozygotic twins - share 100% of the same DNA
what is a concordance rate?
the probability as a % that if one twin has a characteristic the other twin will have the same
what evidence is there for twin studies?
christiansen’s study of twins in denmark (1977)
what are adoption studies in relation to the nature vs nurture debate?
criminal behaviour comes from genetics = nature
criminal behaviour comes from environment = nurture
what evidence is there for adoption studies?
mednick (et al) study on 14,000 adopted male children
what did mednick et al find? (adoption studies)
- found that sons were more likely to have a criminal record if their biological father had one (concordance rate of 20%)
- only 14.7% concordance rate between adoptive parent and son
what did christiansen find? (twin studies)
52% concordance rate for MZ twins
22% concordance rate for DZ twins
what is XYY syndrome and what is it known as?
where an individual is born with an extra Y chromosome.
karyotype or ‘super male’ disease
who came up with the XYY theory?
patricia jacobs
what behaviours are caused by XYY syndrome?
explosive temper/aggression
hyperactivity and impulsivity
antisocial personality