What are twins
Twins refer to two or more babies born to a mother at the same time in the same pregnancy. Twins are divided into identical twins and fraternal twins. Identical twins refer to an egg that splits into two embryos after fertilization and become identical twins that look exactly the same. Fraternal twins are two eggs that were released by the mother at the same time. , fertilized by two different sperm.
What are twins?
Twins refer to a pair of twins in a family, one of whom is a boy and the other is a girl. Dragon and phoenix represent the distinction between men and women respectively in Chinese culture. The emergence of twins is a strange joke of nature, because identical twins have the same chance of having the same gender. However, some research suggests that the foods a pregnant woman eats during early pregnancy and the environment surrounding the fetus may have an impact on the gender of the fetus.
Principles of genetics of twins
Although twins look exactly the same, their differences in personality and intelligence are still very obvious. This is because twins do not have identical genomes. During the process of fertilized egg division, the genome undergoes random mutations, so although the twins have the same DNA sequence, they are very different at the epigenome level. In addition, humans\’ complex gene regulatory networks can also have subtle effects on gene expression during development, leading to differences in twins\’ personality and intelligence.
The formation mechanism of twins
The formation of twins is actually an accidental event. Only one in five identical twins has the chance to become a twin. This is because in identical twins, half of the eggs will split into two embryos after fertilization, but of these embryos, the same-sex fetus is more likely to die than the opposite-sex fetus. In fraternal twins, there is a more complex genetic mechanism, because each fertilized egg has its own independent random sex.
Summary
The formation of twins is a magical and not entirely controllable process. In the long history of human evolution, natural selection has made the existence of twins a survival mechanism. Twin twins are a different variation of twins, symbolizing harmony and happiness in the family. Although there are huge differences in personality and intelligence between twins, they share the same genetic sequence and grow up in different living environments, which brings unlimited possibilities to mankind.
