Pastel Green booklet - Physiological theories Flashcards
what are the 5 biological theories?
Physiological:
Criminal atavism - Lambroso
Somatotyping - Sheldon
Genetic:
Twin studies
Adoption studies
XYY syndrome
What is the criminal atavism theory?
- Created by italian criminologist Cesare Lambroso in 1876
- Compared atavistic i individuals to cavemen
- Born with an innate predisposition to crime “born as criminals” - these with this predisposition are less evolved so more primitive + evolutionary throwbacks.
- Members of human subspecies ‘homo-delinquents’
- Atavism affects a persons behaviour and physiology, facial + cranial features.
What are the principle markers of activism? What are some features? How many of these features do women and men need to be a criminal?
principle markers = strong jaw
heavy brow
more features =
- twisted nose
- excessive cheeckbones
- excessive wrinkles
- recessing forehead
(10 total)
Women must have 3+ of these features to be considered activistic whereas men need 5+
What is the supporting research for Lombroso’s (1870) theory of criminal atavism?
Lombroso studied the facial and cranial features of 383 dead criminals and 3,839 living Italian prisoners.
He concluded that 40% of criminal acts were committed by individuals with atavistic features.
This show a strong correlation between atavism and criminal behaviour.
How can this theory explain criminal behaviour?
- Atavism means individuals more likely to be criminals as homo-delinquents are more wilder, untamed and unable to develop in 1870.
- Primitive nature makes them more aggressive and less intelligent - criminality is hereditary and passed down from ancestors.
-Thieves, murderers sex offenders, women offenders.
What are the 3 strengths of this theory?
1) Supporting evidence. Lombroso’s own research + supported by additional research such as Goring (1913).
2) One of first people to study crime “father of modern criminality” - shifts away from religion, scientific credibility
3) Useful practical applications - can identify those with innate predisposition by examining facial and cranial features - prevent crimes.
what are the three weaknesses of this theory?
1 - reductionist, simple explanation only considers looks
2 -can’t explain all criminals, 40% had atavism, what about the 60? Who didn’t? - only focused on traditional crimes.
3 - deterministic - doesn’t take into account free well moral or religious values
4 - research lacks rigour - doesn’t use controlled group findings of flawed, research conducted by Goring had different results.
what is Sheldon’s theory of somatotyping?
that criminal behaviour is linked to physical form/body type.
Ectomorph - thin, fragile private thoughtful
mesomorph - muscular athletic adventurous domineering
Endomorph - soft body round physique sociable hedonistic
what is a supporting research for Sheldon somatic typing theory?
Sheldon 1949:
assessed tomato types of 200 college students that were non-criminals and 200 delinquents some criminal. He analysed photos of participants and write their level of mesomorph ectomorph and endomorph on a scale of 1- 7, 1low mes, 7 high mes build.
The averages of each level of mes:
students 3.8%, delinquents 4.6%, criminal delinquents 5.4% were mesomorphs.
How does Sheldon’s theory explain criminal behaviour?
muscular build of mesomorphs influenced their personality, making them more self assertive and more likely to engage in criminal activity.
Sheldon believes that mesomorphs builds reflect high levels of testosterone which results in higher levels of aggressiveness and greater chances of committing violent crimes.
Modern research shows testosterone doesn’t cause aggression .
what are the three strengths of Sheldon’s theory?
1) credibility due to supporting research from Glueck and Glueck 1956, found correlation between mesomorphy and criminality.
2) quantity and quality praised- Sheldon used a control group which was a large sample so it was representative.
3) practical applications - useful to investigate and prevent crimes
What are the three weaknesses of Sheldon somatic theory?
1)Fails to acknowledge somatotypes aren’t faced and can change - e.g. in prison less food so skinner and more time to exercise so more mesomorphic builds.
2) Not generalisable - Cant be used to explain all crimes, e.g. John Wayne Gacy was an endomorph, reduces credibility and practical use.
3) Only established correlation between mesomorphy and criminality - fails to provide a definitive cause - reductionist doesn’t consider influences.
What are the 2 types of twins?
Monozygotic - identical
Dizygotic - non-identical
What is the concordance rate?
The chances of 2 people sharing same characteristics traits or behaviours if both people are criminal concordance rate is high if one is then its low.
How do twin studies link to criminality?
They help determine if genetics or environmental influences have caused the behaviour.
What are the 2 supporting research for twin studies?
1) Christiansen 1977 - studied 3586 twins in Denmark, found 52% CR with MZ and 22% CR between DZ- shows genetic link to criminality.
2) Ishikawa & Raine 2002 -> 44% CR for MZ and only 22% CR for DZ - predicted Christiansen’s findings + added further support.
What are the 2 strengths of the twin studies?
1) They’re natural experiments - biological relationships between the twins are naturally occurring events aren’t manipulating variable themselves - high ecological validity, it’s ethical.
2) Supporting evidence - Christian and Ishikawa and Raine - gives more credibility.
What are the 4 weaknesses of 1the twin studies?
1) Reductionist - difficult separate genetic + environmental factors.
2)Methodologically flawed - Christiansen, small sample so can’t generalise, they guessed if twins were MZ or DZ.
3) Not conclusive - Christiansen, not only influenced by genetics.
4) Higher CR isn’t necessarily due to genetics - nurture vs nature.
What are the adoption studies?
- They’re used to test genetic cause of crime - and examine CR between BP and AP and AC - as AC don’t grow up in the same environment as their BP so researchers can see if genetics or environmental has more of an effect on criminal behaviour.
- Findings show AC share more behavioural similarities with their BP - supporting the genetic explanation of crime.
-
What are the 3 studies that support adoption studies?
1) Crowe (1972) - found BM had a criminal record the child had 50% chance of getting one and if BM didn’t it was 5%.
2)Hutchings + Mednick (1984) - 14,000 AC high CR between boys with crim convictions + their BP with convictions - genetic link
3)Mednick et al (1984) - 400 adopted Danish men compared their crim records with their parents ( both BP and AP) no relationship with AP + AC but did find a correlation between BP and AC 20%.
How does this theory of adoption studies support/explain criminal behaviour?
- Findings of Mednick et al 1984 show criminal concordance rate for BP and their children is 20% and higher than the CR between AP and their AC which is 14.7%.
- We can conclude that genes play a large role in criminal behaviour.
What are the 2 strengths of adoption studies?
1)Reliability due to supporting evidence of Hutchings + Mednick (1975) then Mednick at al (1984) - findings increase credibility.
2)Useful research as helps separate genetics from the environment. they separate the 2 factors - clearer explanation.
What are the 2 weaknesses of adoption studies?
1) Methodologically flawed - fail to consider that children can be adopted before 18 so they share same env with BP - study fails to separate g+E, limited applications to society.
2) Reductionist- only focuses on genetic influence - process of adoption is difficult + emotional/ psychological trauma. explanation is overly simplistic.
