L7 - the influence of genes and evolution on behaviour Flashcards
what are genetics
the extent to which a psychological characteristic is determined by genes or the environment
what is a genotype
the genetic code written in the DNA of individual cells inherited from biological parents
consists of genes a person possesses and they can be dominant or recessive
what is a phenotype
the characteristic of an individual is determined by expression or physical, behavioural and psychological traits
2 strengths of genetics
- gene mapping can help psychologists locate genes on chromosomes, highly scientific and objective, involves precise methods of investigation supported by science
- involves using twin and adoption studies, useful for examining MZ who are identical - can help psychologists examine concordance rates
a weakness of genetics
reductionist
takes complex human behaviour e.g. IQ and reduces it down to small components such as genes
inaccurate as IQ is not solely based on genes
other factors such as environment
gottesman and shields twin studies procedure
224 sets of twins (106 MZ)
avg age of 46 from different ethnic backgrounds
longitudinal study following pp over 25 years
relied on one twin having schizophrenia and concordance rates were investigated
included: in depth interviews, doctors case notes, DSM
gottesman and shields twin studies findings
48% of MZ were both concordant for schizophrenia
17% of DZ were both concordant for schizophrenia
MZ twins are more likely to inherit schizophrenia
strength of gottesman and shields
longitudinal
pp tracked over long periods of time to monitor development
more reliable when investigating whether schizophrenia is caused by genetics
2 weaknesses of study by gottesman and shields
- ignores behavioural approach, identical twins often model and copy each others behaviour, healthy twin may be copying behaviour rather than from genetics, therefore must fully investigate how healthy twin gained schizophrenia
- relied on interviews with patients, difficult with speech and communication so difficult to communicate symptoms effectively, negative effect on diagnosis and classification
what is the evolutionary approach
- genetic makeup can undergo mutation due to change in environment, leading to characteristic change in offspring, change may increase survival rate and so gene is passed on and is adaptive
2 strengths of the evolutionary approach
- supported by charles darwin, survival of the fittest, help explain how certain traits become adaptive within a species such as males being tall or giraffes having long necks
- species will compete to have the best mate to reproduce with, maximises chances of healthy offspring, healthy ones pass on genes to next gen helping human/animal species to evolve and adapt
weakness of evolutionary approach
doesn’t take into account behavioural and cognitive explanations for behaviour
idea of every species wanting to reproduce and aid survival takes away idea of free will
not all members of a species have this drive/will make such decisions
research support for evolutionary approach by Buss
investigated what pp looked for in a LT partner
10,000 pp across 37 cultures
18 characteristic with a 4 point rating scale
findings showed females desired makes with money, resources, ambitions / males desired fertile, youthful, kind
weakness of research by buss
research by buller contradicts
questioned idea that females prefer males with high status and resources
females in todays contemporary society are independent, use own resources and do not reply on mate to financially provide
strength of research by Buss
cross cultural validity about evolutionary approach
females want to be protected and cared for
supported by females believe a man with resources can look after her and future offspring - stability
