Every individual on this earth is different from the other. No one person is fully like other person.
Many researchers believe that there is a reaction range to IQ, which refers to the limits placed on IQ by heredity. Heredity places an upper and lower limit on the IQ that can be attained by a given person. Despite the prevailing view that both heredity and environment influence intelligence, researchers still have different opinions about how much each contributes and how they interact.
Hereditary Influences Evidence for hereditary influences on intelligence comes from the following observations: Family studies show that intelligence tends to run in families. Twin studies show a higher correlation between identical twins in IQ than between fraternal twins.
This holds true even when identical twins reared apart are compared to fraternal twins reared together. Adoption studies show that adopted children somewhat resemble their biological parents in intelligence. Family studies, twin studies, and adoption studies, however, are not without problems. See pages —38 for more information about the drawbacks of such studies.
Estimates of the heritability of intelligence vary, depending on the methods used. Most researchers believe that heritability of intelligence is between 60 percent and 80 percent. Heritability estimates apply only to groups on which the estimates are based.
So far, heritability estimates have been based mostly on studies using white, middle-class subjects. Even if heritability of IQ is high, heredity does not necessarily account for differences between groups. Three important factors limit heritability estimates:The Influence of Heredity and Environment Today, researchers generally agree that heredity and environment have an interactive influence on intelligence.
Many researchers believe that there is a reaction range to IQ, which refers to the limits placed on IQ by heredity. Heredity, no doubt has its influence on the physiological traits but environment is also the arbiter of our development.
What heredity can do environment can also do. Neither can ever be eliminated and neither can ever be isolated. The field of behavioral genetics aims at understanding the observable differences in a wide variety of human characteristics, typically by analyzing the contributions made by heredity and environment in the development of the characteristics in question.
Heredity and Environmental influences and its Effects. Print Reference this. Published: 23rd March, Although a person's environment plays an important part in their personality development, heredity factors play a larger role in deciding disposition of this environment.
HEREDITY VERSUS ENVIRONMENT. Many aspects of human characteristics (such as height and eye color) are largely genetically determined. Psychology researchers, however, tend to be interested in dimensions that are relatively less determined by genetics—traits that subject more to environmental influences, such as how a person feels, acts, and thinks.
While some aspects of development may be strongly influenced by biology, environmental influences may also play a role. For example, the timing of when the onset of puberty occurs is largely the results of heredity, but environmental factors such as nutrition can also have an effect.