Igbo-Ora, Nigeria : The "Twins Capital of the World".
For many years now it has been a well known fact that twins are very common among the Yoruba people, by far the dominant ethnic group in the south west part of Nigeria. A study done in the 1970s showed that around 50 sets of twins were born out of every 1,000 births in the southwest - one of the highest rates of twin births in the world.
In Igbo-Ora, ( also spelled Igbo Ora, and pronounced "Ibo-ora" ) in Oyo State and also in south west Nigeria, (approximately 140 kilometers north of Lagos), the rate is much higher. In the local high school almost 20% of the students have a twin sibling. In the Yoruba culture twins are so common that they are traditionally given specific names. Traditionally the Yoruba people name their male twins either Taiwo or Kehinde depending on whether they were born first or second. For Nigerians it is common knowledge that if you meet a man named Taiwo, you can be pretty sure that he has a twin brother named Kehinde. The locals believe that the high percentage of twins among them is not a genetic or hereditary matter, but rather somehow related to the Okra they eat in their traditional cuisine, there is however no scientific proof of that.