twin and adoption studies (pack 3) Flashcards
How are twin studies done?
MZ twins (identical) and DZ twins (non-identical) are compared…if there is a genetic component, MZ twins would be more similar that DZ
How are adoption studies done?
concordance rates between adoptee and adopted are compared to adoptee and biological parents…higher rate in adoptee-bio
what is the rationale of twin studies
if a member of a twin has roughly identical environments, any difference when comparing the similarities must be due to genetic difference
two strengths of twin studies?
scientific cred. is high, allows them to study empirically, the influence of nature nurture
research provided is objective and quantitative
evidence from twin studies can be very important info when seeking preventions and treatments
2 weaknesses of twin studies?
scientific cred. lowered due to confounding variables …environmental influences too…valisity has been lowered as data on genetics cannot be confounded as they can’t be sure that it isn’t also environment influencing our behaviour
generalising from results of twin studies is difficult as samples in twin studies are often very small and do not represent the wider population as they are not twins
one strength of adoption studies
clearer isolation of environmental influences than twins
twins are still similar but have not shared an environment and can be surer of validity
allows them to suggest genes have an influence on traditionalism
two weaknesses of adoption studies
scientific cred lowered by confounding variables as they do not account for the fact that adoptive families are chosen due to similarity of bio parents AND child may have spent time with bio families before adoption…so CANNOT be sure any results are completely accurate because upbringing may be a confounding variable
generalising- samples are small and atypical as most don’t get adopted, no generalising to wider population
