Discuss the nature-nurture debate (16 marks)
The nature-nurture debate is concerned with to what extent aspects of our behaviour are a product
of our genetics or our environment. Nature suggests that our biological make up such as genes and
heredity can influence our behaviour, whereas nurture suggests we acquire characteristics and are
influenced by our environment. The debate has a long history of research. Descartes, a nativist (1596
– 1650), argued that human characteristics are innate, due to heredity and are biologically
deterministic. In contrast to this, Locke, an empiricist (1632 – 1704), argued alongside the
behaviourists that a baby´s mind is a “blank slate” at birth (tabula rasa). This is then filled in and
altered through experiences via the environment.
Plomin (1994) designed a heritabilty co-efficient which is used to assess heredity. It is a number
between 0 and 1, which indicates the extent to which any measurable characteristics is due to
genetics. A value of 1 would be entirely genetic and 0 would be entirely due to the environment.
Intelligence is usually around 0.5 which suggests there is an equal interaction between nature and
nurture. Lerner (1986) suggested that we can consider the enviroment quite narrowly (level 1) or
more broadly as we go up to levels 2 and 3, implying that environmental influences can act even
before the baby is born.
A complication of the nature-nurture debate is that even siblings raised within the same family will
experience a slightly different upbringing. This may explain why monozygotic twins reared together
do not show perfect concordance rates, even though they share 100% of their genes and their home
environment. Twin studies do not disentangle the nature-nurture debate. Instead, adoption studies
are a better measure of the relative contributions of nature and nurture in explaining a particular
characteristic of human behaviour.
The diathesis stress model acknowledges a contribution of both nature and nurture in human
characteristics and behaviour. Candidate genes can give someone a genetic predisposition or
vulnerability to a disorder, but there needs to be an environmental stress or trigger in order for the
disorder to develop. The stronger the diathesis, the less stress that is needed to produce the
disorder. Environmental stressors include factors such as significant life changes, trauma and abuse.
The interactionist approach is the idea that nature and nurture are interlinked to such an extent that
it does not make sense to separate the two, so researchers instead study how they interact and
influence each other. Constructivism, which is a particular type of interactionism, suggests that
people create their own “nurture” by consciously or unconsciously selecting environments that are
appropriate for their “nature”. Plomin named this “niche picking and niche building” and he argues
that it is impossible and illogical to try and seperate nature from nurture in explaining a child’s
behaviour.
Epigenetics is the study of the changes in genetic activity caused by modification of gene expression,
instead of altering of the genetic code itself. Epigenetics suggests that aspects of our lifestyle, such
as how stressed we are, pollution and smoking exposure, can leave epigenetic “tags” on our DNA
and life experiences of previous generations can influence health of future generations. These “tags”
can influence how our cells read the genetic code therefore influence the protiens that our cells
make. These epigenetic tags also determine which genes are switched on and off and as a result
some epigenetic tags may be inherited, which increases the validity of Lamarkism’s research. This
introduces a third element into the nature-nurture debate, which is the life experience of previous
generations.
The nature-nurture debate is concerned with to what extent aspects of our behaviour are a product
of our genetics or our environment. Nature suggests that our biological make up such as genes and
heredity can influence our behaviour, whereas nurture suggests we acquire characteristics and are
influenced by our environment. The debate has a long history of research. Descartes, a nativist (1596
– 1650), argued that human characteristics are innate, due to heredity and are biologically
deterministic. In contrast to this, Locke, an empiricist (1632 – 1704), argued alongside the
behaviourists that a baby´s mind is a “blank slate” at birth (tabula rasa). This is then filled in and
altered through experiences via the environment.
Plomin (1994) designed a heritabilty co-efficient which is used to assess heredity. It is a number
between 0 and 1, which indicates the extent to which any measurable characteristics is due to
genetics. A value of 1 would be entirely genetic and 0 would be entirely due to the environment.
Intelligence is usually around 0.5 which suggests there is an equal interaction between nature and
nurture. Lerner (1986) suggested that we can consider the enviroment quite narrowly (level 1) or
more broadly as we go up to levels 2 and 3, implying that environmental influences can act even
before the baby is born.
A complication of the nature-nurture debate is that even siblings raised within the same family will
experience a slightly different upbringing. This may explain why monozygotic twins reared together
do not show perfect concordance rates, even though they share 100% of their genes and their home
environment. Twin studies do not disentangle the nature-nurture debate. Instead, adoption studies
are a better measure of the relative contributions of nature and nurture in explaining a particular
characteristic of human behaviour.
The diathesis stress model acknowledges a contribution of both nature and nurture in human
characteristics and behaviour. Candidate genes can give someone a genetic predisposition or
vulnerability to a disorder, but there needs to be an environmental stress or trigger in order for the
disorder to develop. The stronger the diathesis, the less stress that is needed to produce the
disorder. Environmental stressors include factors such as significant life changes, trauma and abuse.
The interactionist approach is the idea that nature and nurture are interlinked to such an extent that
it does not make sense to separate the two, so researchers instead study how they interact and
influence each other. Constructivism, which is a particular type of interactionism, suggests that
people create their own “nurture” by consciously or unconsciously selecting environments that are
appropriate for their “nature”. Plomin named this “niche picking and niche building” and he argues
that it is impossible and illogical to try and seperate nature from nurture in explaining a child’s
behaviour.
Epigenetics is the study of the changes in genetic activity caused by modification of gene expression,
instead of altering of the genetic code itself. Epigenetics suggests that aspects of our lifestyle, such
as how stressed we are, pollution and smoking exposure, can leave epigenetic “tags” on our DNA
and life experiences of previous generations can influence health of future generations. These “tags”
can influence how our cells read the genetic code therefore influence the protiens that our cells
make. These epigenetic tags also determine which genes are switched on and off and as a result
some epigenetic tags may be inherited, which increases the validity of Lamarkism’s research. This
introduces a third element into the nature-nurture debate, which is the life experience of previous
generations.
