Published on The Himalayan Times,
14th June 2005
Everyone wants to be more intelligent. Everyone wants to get more marks in mathematics and pass interviews easily. But intelligence cannot be developed within a few days. It is also something inherited as genes that you are carrying and is governed by multiple environmental factors.
Everyone wants to be more intelligent. Everyone wants to get more marks in mathematics and pass interviews easily. But intelligence cannot be developed within a few days. It is also something inherited as genes that you are carrying and is governed by multiple environmental factors.
In many cases, it is found
that there is difference in intelligence level among members of the same
family, growing in the same family environment. In other cases, family members
or even twins reared apart and growing in different environments possess
similar levels of intelligence.
Yet another research carried
out in some identical twins on the basis of IQ tests, it can be safely
concluded that social and educational environmental differences may strongly
affect intelligence despite genetic similarities. In some experiments
conducted, a particular pair of twins who were reared apart differed by 24 IQ
points; one completed college and became a schoolteacher while other did not
finish school. But, this may be also have happened due to lifestyle choices.
Another pairs of twins
reared apart difference only by 1 IQ point although one was raised by a well to
do physician while a truck driver raised another. This finding sows that the
identical twins reared apart do not achieve the same differences in IQ scores.
It also points to the possibility that the genetic similarities influencing
that portion of intelligence reared in this fashion are not completely thrown
off track by environmental differences.
Existence of genetic factors
can also be measured in another fashion. The closer the relationship between
two individuals, the more similar their IQ test scores, Thus the IQs of
children and their natural parents are more closely correlated than the IQs of
children and their foster parents. At the same time, however, individuals with
the same degree of relation who were reared together show more similar IQ test
scores than those reared apart. Therefore it is found that both genetic and
environmental factors play a role in intelligence.
Some factors that affect
intelligence are as follows.
1. Size of family
A number of studies have
shown that greater the number of children in a family, the lower the IQ level
per child. The IQW level depends to some degree on the attention given to an
individual during his development and children in large families usually have
less opportunity of getting adequate attention. More interestingly the
particular birth order of a child in a family is believed to be associated with
intelligence. It is found that the first born child achieves better IW scores
than his later born siblings. The reason is still unknown and it can hardly be
caused by basic genetic differences.
2. Cultural effects

3. Early environment
The development of the perceptive
and problem-solving skills that are reflected in intelligence sores often
depends up on stimuli and encouragement that infants and young children
receive. It is known that experimental animals deprived of stimuli during early
ages will show intellectual retardation. In humans, the early, stimuli depend
on the mother.
4. Diet
It is seen that protein
deprived females will produce offspring with a reduced number of brain cells.
This effect is also accompanied by kidney deficiencies and other severe body
difficulties. Therefore, dietary deficiencies caused by social and economic
factors play a role in IQ.
The tests on relationships between
IQ scores based on family size, birth order and social groping were performed
during 1963-1966 on about 40,000 males in Netherlands, all 19 years of age who
were examined to determine their fitness for military duty.