Why are studies of identical twins raised in different environments extremely valuable in understanding the causes of a disease? They are extremely valuable in understanding the causes of a disease, because it differentiates between nature vs. nurture.
Why are studies of identical twins important?
We study twins to understand how much of the difference in a trait between people is caused by genes and how much is caused by the environment. These studies are important because they help scientists quantify genetic and modifiable environmental factors that increase the risk of certain diseases .
Why are identical twins often used in research studies?
Twins provide a valuable source of information for health and psychological research, as their unique relationship allows researchers to pull apart and examine genetic and environmental influences. ... Twin studies allow researchers to examine the overall role of genes in the development of a trait or disorder .
What are the disadvantages of twin studies?
Limitations of twin studies
Results from twin studies cannot be directly generalized to the general population , due to lack of randomization; in addition, they are different with regard to their developmental environment, as two fetuses growing simultaneously.
What do twin studies tell us about intelligence?
Genes have a very strong influence over how certain parts of our brains develop , scientists in the US and Finland have found. In identical twins, these areas showed a 95 to 100 per cent correlation between one twin and the other – they were essentially the same. ...
Do identical twins raised apart have similar personalities?
Comparing twins raised separately with those raised in the same home allows researchers to determine the relative importance of heredity and of environment in their development. Although some twins go out of their way to emphasize differences between them, in general identical twins are very much alike in personality .
What are two conclusions of Bouchard's study?
The research team found that identical twins who are reared apart had the same chance of being similar as twins who were raised together . Bouchard and his colleagues concluded that genetic factors have a large influence on behavioral habits demonstrating the influence of the genetics on development.
It is true that identical twins share their DNA code with each other . This is because identical twins were formed from the exact same sperm and egg from their father and mother. (In contrast, fraternal twins are formed from two different sperm and two different eggs.)
Why are twin studies unethical?
The study, which has since been criticized for being unethical — for example, neither the children's biological parents nor the adopting families were informed — was an attempt to get at the central psychological questions of “nature versus nurture” and the “twinning reaction.”
Are twin studies reliable?
Twins provide a valuable source of information for health and psychological research, as their unique relationship allows researchers to pull apart and examine genetic and environmental influences. Twin study findings have been influential in detecting and treating various diseases and psychological disorders .
Are twin studies valid?
Many of the criticisms of twin studies are unjustified. Twins are indeed representative of the general population for a wide range of traits and diseases, and available evidence strongly suggests that twin studies do not violate the equal environments assumption.
What is the IQ of identical twins?
By then they had measured the IQ of 48 pairs of monozygotic, or identical, twins, raised apart (MZA) and 40 pairs of such twins raised together (MZT). The MZA twins were 69% similar in IQ, compared with 88% for MZT twins, both far greater resemblances than for any other pairs of individuals, even siblings.
Do twins have lower IQ?
On average, twins have lower IQ scores at 7 and 9 years old than singleton children in the same family. In a cohort study, Ronalds and colleagues (p 1306) used data on 9832 singletons and 236 twins born in Aberdeen between 1950 and 1956.
Is IQ learned or inherited?
Researchers have previously shown that a person's IQ is highly influenced by genetic factors , and have even identified certain genes that play a role. They've also shown that performance in school has genetic factors. But it's been unclear whether the same genes that influence IQ also influence grades and test scores.
What results in identical twins?
To form identical or monozygotic twins, one fertilised egg (ovum) splits and develops into two babies with exactly the same genetic information . To form fraternal or dizygotic twins, two eggs (ova) are fertilised by two sperm and produce two genetically unique children.
Who was famous for studying identical twins?
In 1979, Thomas Bouchard conducted what is perhaps the most fascinating twin study yet. Then director of the Minnesota Center for Twin and Family Research, Bouchard looked at identical and fraternal twins separated in infancy and reared apart.
