Nature vs. Nurture Essay

Good Essays

Today most interest in twins serves to determine whether traits come from ones environment or from genetics. However, throughout time, twins have been a constant source of entertainment and amazement for society. Twins differ very little, and according to an e-mail interview with Dr. Nancy Segal, the American attraction to them is due to our high value and appreciation of independency and personal differences. Segal believes the similarity of twins contrasts greatly with Americans values and this contrast sparks interest, almost to the nature of a circus sideshow. Because most singletons find the eerie alikeness of twins mystifying, myths and urban legends about twin behavior are not uncommon. For instance, the belief twins share more …show more content…

Scientists cite these and other interesting reasons as impetus for studying twins. However, the majority of twin studies serve to determine whether genetics or environment decide human traits.
Studies of twins place them in two differing groups. Identical twins or monozygotic twins, according to Clegg and Woollett, "are formed by the accidental splitting of a single fertilized egg, so that the babies develop from one egg and one sperm." They also define fraternal or dizygotic twins as non-identical twins that "develop from the fertilization of two eggs by two sperm" (16). It is common knowledge ones genes are inherited, half from ones mother, and half from ones father. Since monozygotic, or MZ, twins are a split of the same egg and sperm, they contain identical genes. However, the genes of dizygotic, or DZ, twins are only as similar as typical brothers and sisters. Scientists are interested in fraternal twins reared together because, being the same age and in the same home, they share practically identical environments. They are also interested in studying identical twins that have been reared apart from one another, because they share identical genetics but have differing backgrounds. These groups of twins provide researchers with automatic control groups.
By studying these two groups, scientists can see if DZ twins with the same environment are

Get Access
Get Access