Hutu and 14% of residents in Rwanda and Burundi, respectively. The Twa pygmies, the smallest of the two countries' principal populations, also share language and culture with the Hutu and Tutsi. However, they are distinguished by a considerably shorter stature. The Hutu are believed to have first emigrated to the Great Lake region from West Africa in the great Bantu expansion. Various theories have emerged to explain the purported physical differences between them and their fellow Bantu-speaking neighbors, the Tutsi. One such thesis, largely based on oral tradition, posits that the Tutsi experienced some admixture with or were partially descended from
Origins of Hutu, Tutsi and Twa the importance of the pastoralist migrations. Still other studies point out that cultural transmission can occur without actual human migration. This raises the question of how much of the changes around the fifteenth and sixteenth centuries was the result of an influx of people as opposed to the existing population being exposed to new ideas. Studies that approach the subject of racial purity are among the most controversial. These studies point out that the pastoralist migrants and pre-migration Rwandans lived side by side for centuries and practiced extensive intermarriage. The notion that current Rwandans can claim exclusively Tutsi or Hutu