The nature-nurture debate:
What is the nature-nurture debate? (definition)
The nature-nurture debate focuses on the relative importance of hereditary and the
environment in determining human behaviour.
Essentially it focuses on the degree to which genes (nature) and the environment (nurture)
play a role in determining human behaviour.
Nature
The nature side of the debate argues hereditary is more influential in determining human
behaviour. The nature aspect is rooted in the nativist theory where individuals such as
Descarte argue that human characteristics and even some aspects of knowledge and
abilities are innate (in our genes).
The heritability coefficient is used to assess heredity on a scale of 0 to 1. O means the
characteristic has no genetic basis and 1 means the characteristic is completely due to
genetics. The heritability for IQ is 0.5.
An example of the relative importance of heredity
Twins studies are often used to assess the relative importance of nature in influencing
behaviour.
A study conducted by Gottesman (1991) found the concordance rate of schizophrenia for
MZ twins was 48% compared to 17% for
DZ twins. Therefore, supporting the idea that nature plays an important role in determining
schizophrenia.
Nurture
The nurture side of the debate assumes environment and experience is more influential in
determining human behaviour. Nurture is rooted in empiricist theory that knowledge derives
from learn-ing. One empiricist is Locke who viewed the mind as a blank slate on which
experiences are written.
An example of the relative importance of the environment
The SLT suggested that behaviour is learnt in a social context through a process of
observation and imitation of role models behaviour. This explanation has been used to
explain behaviours such as aggression where an individual has learnt aggressive behaviours
via observing aggressive role models and imitating their behaviour.
This can be illustrated in Bandura et als Bobo Doll study.
Interactionist approach
From a practical point of view it is impossible to answer the relative importance of hereditary
and environment as nature and nurture are so closely intertwined making it impossible to
fully separate and study the two. Therefore the interactionist approach suggests that human
behaviour is determined by both nature (genes) and nurture (environment). It does not make
sense to separate the two. For example, there is over whelming evidence that schizophrenia
runs in families therefore suggesting that an individual is born with a gene that makes them
more vulnerable to schizophrenia. However, schizophrenia is only developed when an
individual experiences an environmental trigger (stressor) such as dysfunctional family
, relationships. Hence genes and the environment together cause schizophrenia. This is
known as the diathesis-stress model.
Evaluating the nature-nurture debate
● Positive - Point 1:
There are implications of accepting nurture as the primary driver of behav-iour. The
empiricist view (nurture) suggests that behaviour can be shaped and changed by altering the
environment.
Evidence: For example, therapies such as systematic desensitisation and flooding are
successful treatments for phobias which work by changing and shaping the individuals
behav-
Therefore: this can have positive implications as it offers a form of treatment providing a
positive outlook for a patient. Although some would argue that this view advocates a model
of society that controls and manipulates society.
● Negative - Point 2:
In contrast there are serious implications of accepting nature as the primary driver of
behaviour as it would suggest that our behaviour is determined by our genes of which we
have no control (determinism).
Evidence: This can lead to examples where by certain races are seen to have low IQ due to
their genes which is not the case or have implication for the justice system and prison
systems.
Therefore: This view could have serious and somewhat controversial consequences within
society resulting in discrimination and scientific racism. Recognising human behaviour is
determined by both nature and nurture is a much more reasonable approach.
● Negative - Point 3:
Although there is clearly supporting evidence for nature driving behaviour this is not
conclusive.
Evidence: For example, twins studies do not show 100% concordance rates for MZ twins
despite them sharing 100% of their genes. Perhaps nurture or individual differences in twins
may influence how each twin responds to life events causing differences.
Therefore: this could account for why the concordance rates for MZ twins is not 100% when
looking at behaviour. Ultimately highlighting how both hereditary and environment cannot be
meaningfully separated. Therefore it is important to acknowledge that both nature and
nurture determine human behaviour.
● Positive - Point four:
This has lead to the positive proposal of a interactionist approach when
explaining and treating behaviour which acknowledges both the role of nature and nurture in
determining behaviour.
What is the nature-nurture debate? (definition)
The nature-nurture debate focuses on the relative importance of hereditary and the
environment in determining human behaviour.
Essentially it focuses on the degree to which genes (nature) and the environment (nurture)
play a role in determining human behaviour.
Nature
The nature side of the debate argues hereditary is more influential in determining human
behaviour. The nature aspect is rooted in the nativist theory where individuals such as
Descarte argue that human characteristics and even some aspects of knowledge and
abilities are innate (in our genes).
The heritability coefficient is used to assess heredity on a scale of 0 to 1. O means the
characteristic has no genetic basis and 1 means the characteristic is completely due to
genetics. The heritability for IQ is 0.5.
An example of the relative importance of heredity
Twins studies are often used to assess the relative importance of nature in influencing
behaviour.
A study conducted by Gottesman (1991) found the concordance rate of schizophrenia for
MZ twins was 48% compared to 17% for
DZ twins. Therefore, supporting the idea that nature plays an important role in determining
schizophrenia.
Nurture
The nurture side of the debate assumes environment and experience is more influential in
determining human behaviour. Nurture is rooted in empiricist theory that knowledge derives
from learn-ing. One empiricist is Locke who viewed the mind as a blank slate on which
experiences are written.
An example of the relative importance of the environment
The SLT suggested that behaviour is learnt in a social context through a process of
observation and imitation of role models behaviour. This explanation has been used to
explain behaviours such as aggression where an individual has learnt aggressive behaviours
via observing aggressive role models and imitating their behaviour.
This can be illustrated in Bandura et als Bobo Doll study.
Interactionist approach
From a practical point of view it is impossible to answer the relative importance of hereditary
and environment as nature and nurture are so closely intertwined making it impossible to
fully separate and study the two. Therefore the interactionist approach suggests that human
behaviour is determined by both nature (genes) and nurture (environment). It does not make
sense to separate the two. For example, there is over whelming evidence that schizophrenia
runs in families therefore suggesting that an individual is born with a gene that makes them
more vulnerable to schizophrenia. However, schizophrenia is only developed when an
individual experiences an environmental trigger (stressor) such as dysfunctional family
, relationships. Hence genes and the environment together cause schizophrenia. This is
known as the diathesis-stress model.
Evaluating the nature-nurture debate
● Positive - Point 1:
There are implications of accepting nurture as the primary driver of behav-iour. The
empiricist view (nurture) suggests that behaviour can be shaped and changed by altering the
environment.
Evidence: For example, therapies such as systematic desensitisation and flooding are
successful treatments for phobias which work by changing and shaping the individuals
behav-
Therefore: this can have positive implications as it offers a form of treatment providing a
positive outlook for a patient. Although some would argue that this view advocates a model
of society that controls and manipulates society.
● Negative - Point 2:
In contrast there are serious implications of accepting nature as the primary driver of
behaviour as it would suggest that our behaviour is determined by our genes of which we
have no control (determinism).
Evidence: This can lead to examples where by certain races are seen to have low IQ due to
their genes which is not the case or have implication for the justice system and prison
systems.
Therefore: This view could have serious and somewhat controversial consequences within
society resulting in discrimination and scientific racism. Recognising human behaviour is
determined by both nature and nurture is a much more reasonable approach.
● Negative - Point 3:
Although there is clearly supporting evidence for nature driving behaviour this is not
conclusive.
Evidence: For example, twins studies do not show 100% concordance rates for MZ twins
despite them sharing 100% of their genes. Perhaps nurture or individual differences in twins
may influence how each twin responds to life events causing differences.
Therefore: this could account for why the concordance rates for MZ twins is not 100% when
looking at behaviour. Ultimately highlighting how both hereditary and environment cannot be
meaningfully separated. Therefore it is important to acknowledge that both nature and
nurture determine human behaviour.
● Positive - Point four:
This has lead to the positive proposal of a interactionist approach when
explaining and treating behaviour which acknowledges both the role of nature and nurture in
determining behaviour.
