What makes someone an introvert or extrovert?

He said the differences between these personality types are essentially down to energy. Extroverted people often receive energy by social interactions, while introverts need time alone to recharge. Introverts have a lot of the chemical that makes them feel stimulated; extroverts don’t have so much.

How can two twins have some traits that are similar and some that are so different?

Identical twins share all of their genes, while non-identical twins, just like non-twin siblings, share half of their genes. So, we can assume that any differences in traits between identical twins come from the environment, and not from differences in their genes.

Why do identical twins end up having such different lives?

After all, identical twins have the same genes, share the same womb and usually experience the same childhoods. By comparing identical and fraternal twins and their sensitivities to illnesses, it is possible to separate the genetic roots of conditions from their environmental influences.

Do identical twins have the same personality traits?

In study after study, twins have been found to have very similar personalities. A study from Edinburgh University on over 800 sets of twins found that identical twins were twice as likely to have shared personality traits as fraternal twins.

How do identical twins differ?

Identical twins share all of their genes and are always of the same sex. In contrast, fraternal, or dizygotic, twins result from the fertilization of two separate eggs during the same pregnancy. They share half of their genes, just like any other siblings. Fraternal twins can be of the same or different sexes.

Do identical twins have the same blood type?

5 Monozygotic (identical) twins will have the same blood type, with a few very rare exceptions. Dizygotic (fraternal) twins may have the same blood type, or they may have different types.