The Yibir are descendants of Muhammed bin Hanif, known as "Boqor Bur Bayr", who was the king of Hargeisa in the 11th or 12th century
The Yibir are descendants of Muhammed bin Hanif, known as "Boqor Bur Bayr", who was the king of Hargeisa in the 11th or 12th century. According to legend Yuusuf al-Kawnayn defeated him in a battle of religious power and trapped him in a mountain, and that because of this the Somali owe blood debt to all of his descendants.
Most of the tribes listed above live in Ceerigaabo and live among one clan or another that lives in that city. Only the Madhibaan are really despised, but I believe that has more to do with history, as Madhibaan were feared for centuries for being armed with deadly poison tipped arrows and excellent bowmen, who would twang their bowstrings if they were feeling malicious.
The history of the "Pre-Somali" is a mystery to me, and I don't think that they have been the subject of anyone's study. For instance many Somali do not know that they keep their own Abtirsi, but they do. The Tumal, Yibir and Madhibaan for instance are a clan group, referred to as the Baidari.
Special ceremonies surround the birth of children. After a woman gives birth, the baby is dedicated at 7 days of age. The woman stays secluded for a total of 40 days. There is a feast with the other women in the village and the baby is dedicated again. The ceremony ends with the women dancing.
Yibir Pre-Islamic Religious Specialists theory
Christian Bader (2000: 167-71) has established a strong case for believing that the Yibir derive from clans or lineages that, in pre-Islamic times, included highly religious specialist. He compares them to the Ibir moiety of the Rendille. The Ibir of Rendille like the Yibir Somali has the power to bless or curse and manipulate special prayer sticks though the freely intermarry with the Rendille.
Some ordinary Somali, banished by their clan own clans in punishment of their heinous actions, have also joined the other minority groups. Aweer accepted ordinary Somali into their group.
The Character of Kinship Tal Tamari p158