Turko-Mongolian mythology is essentially monotheistic. The Supreme Being is Tengri (see Tengri), the Sky personified. The Yakuts call him “The White Master Creator.” To some Tartars he is Ulgen (Ulgan). His assistant spirits are tengri (see Siberian Spirits). Tengri watched over the cosmos and the human social order and later was assimilated into the Muslim (see Islam) concept of the one God or Allah. Other deities were aspects of Tengri, whether Odlek, the personification of Time or Umai (see Umai) the embodiment of the placenta and childbirth and sometimes the Earth itself. Animals, especially the wolf, the bear (a father-man in disguise), and the eagle were important figures. The Turko-Mongols believed in the life of the soul after death and in the power of shamans (see Shamanism) to communicate with spirits (see Siberian Shamanism). Origin myths were popular among the TurkoMongols. The great Mongol conqueror Gengis Khan, was deified and was said to have been a descendant of the union between the Blue Wolf and a wild doe. The ancient Turko-Mongol ancestor Alp Kara Aslan (Heroic Black Lion) was born of a woman raised by an eagle. He was suckled by a lioness. The hero Uighur Buqu Khan, parented by two trees, was born of a knothole (see Virgin Birth). Other heroes and heroines were miraculously conceived by rays of light and various animal combinations (see Tu'chueh, Central Asian Mythology, Siberian entries).