In west Africa. A place called Yoruba has the highest Twin birth rate in the world. This is thought do to a specific yam that they eat. Do to there huge amount of twin rate they came up with a tradition. In Yoruba they give names to each twin born. For example the first twin born is known as Taiyewo, however the second born is known as Kehinde. This translates to "The first born" and "The second born". It is believed in Yoruba that Kehinde sends Taiyewo first to see what the world is like. So Taiyewo is the slave running ahead to welcome the king to the world. Now it is believed that the second born is also named Omokeindegbegbon which translates to "The last one born becomes the elder." That's all thanks for reading. I got this information from wikipedia so all the credit goes to it. Bye.