1. There are 3 types of twins
Many people think that there are only 2 types of twins: identical and fraternal. But there is, in fact, a 3rd type of twins. These are called "mirror image twins". Their hair falls in opposite directions, and if one is a righty, the other is normally a lefty. In theory, if these twins face each other, it would be like looking into a mirror.
2. There is a name for the study of twins
"Gemellology" is the scientific name for the study of twins.
3. Left-handedness is a twin thing
There is a 22% chance that twins will be left handed, whereas the rest of the world only has a 10% chance.
4. The number of twins being born is rising
There has been a 76% increase in the amount of twins being born in the US since 1980.
5. Nigeria has the highest rate of multiple births.
They also have more identical twins than fraternal.
6. Having twins is genetic...
But only the fraternal kind. Identical twins are random, and there is no "identical twin gene".
7. There is only one family in the world that has successfully given birth to octuplets.
Nadya Suleman gave birth to octuplets on January 26th, 2006. There are 6 boys and 2 girls.