Nature vs Nurture Flashcards
Nature
– Deterministic -
– It’s all in our DNA
– Biological
Nurture
- Blank slates
- It’s all experience
- Social sci. perspective
Early views
Francis Galton (1822-1911)
-Wrote Hereditary Genius (1869)
-Believed intelligence was largely inherited
-Conducted early twin studies
• Plato and Aristotle also argued the relative influence of
nature vs. nurture.
Little Albert experiment
Tried to condition fear (in this case of furry things) in a small child. Allegedly worked, but ethically and scientifically unsound.
Evidence for Innate Behaviour
Fixed action patterns – Rigid, stereotyped motor behaviours Species-specific behaviours • Behaviours performed by all members of a species regardless of rearing -Human universals: smiling, greeting “eyebrow flash” Naïve behaviour of young animals - e.g. Visual cliff paradigm Isolation experiments -Development of birdsong
Problems with concept of innate behaviour:
- Behaviour is not preformed in genetic material – what about development?
- Environment is broader than just learning e.g. self stimulation
- Isolation experiments – impossible to remove all the environmental input
Interactionist paradigm
Contingency of gene action; biological is not inevitable; development requires many “ingredients”
Both biology and environment interact throughout development to produce the phenotype
Phenotypic Plasticity
The way in which an organism responds to environmental variation (either during morphological development or behaviourally) is itself likely to be programmed genetically
• E.g. height
IQ
- Formal quantitative genetic models of the inheritance of intelligence have been controversial.
- Dates back to Galton and the 19th C
- Explored by twin methods, MZ/DZ twins reared together vs. reared apart.
Fox P2 gene and the evolution of language
• Located at chromosome 7 • Codes for protein needed for language development • Failure of normal language acquisition • Hereditary, suggesting a genetic cause -the K’s, UK, grandmother, 4 out of her 5 children, • 11 out of 23 grandchildren • Intelligence not affected • ‘the language gene” -But other genes involved too!!
Sex differences in general behaviour
Influenced by imprinting on the X
- The extent of the behavioural difficulties found in Turner’s syndrome girls (XO) is influenced by whether their X is from their mother or their father
• Those with the X from their mother have more behavioural characteristics usually associated with boys