Twin studies:

Twins reared together - have a similar environment. If MZ's are more similar than DZ's it shows the importance of genes
twins reared apart - allows genes and environment to be seperated

Evaluation:
+no other way of studying genes - MZ twins share 100% of their DNA
+Share their environment so their is natural control of environmental effects
-Most people aren't twins so the results don't necessarily generalise to the whole population
-MZ's may have a more similar environment than DZ's so comparisons can be difficult

Adoption Studies:

Most direct way to isolate genes and environment. Any similarities between child and biological parent suggests a role for genes. Any similarity between child and adoptive parent suggests the role of environment.

Evaluation:
+direct comparison of the influence of nature v nurture because they isolate environment from genes.
+can investigate a range of variables and use varied samples/methods.
-still shared same intrauterine environment which could account for similarities in behaviour
-most people aren't adopted so cannot be generalised.

	Created by sophiesmith11 over 11 years ago

Psychology Note on Biological Approach, created by sophiesmith11 on 29/04/2013.

Biological Approach