Twin study

Question 1

Theory summary

Answer 1

If identical twins have 100% the same genes, then if their behaviour is
also the same it could be taken as evidence that genes caused the
behaviour

Question 2

Core

Answer 2

CORE KNOWLEDGE - Concordance means how much
agreement there is between two factors – how similar they are.
We can use this when talking about the similarity between twins
- in terms of crime.High concordance = they both similar Low
concordance = they are different. Concordance rates are
higher in Monozygotic twins (identical twins) than in
Dizygotic twins (non-identical)

Question 3

Study

Answer 3

Lange (1929) found that 10 out of 13 MZ twins had both served time in
prison, whereas only 2 out of 17 DZ twins had.

Question 4

Study 2

Answer 4

Christiansen (1977) study of twins 3,586 - who found there were higher
concordance rates for MZ twins than DZ twins - both males and femaleS