text: Members of this profession were often buried in hollowed-out trees rather than the ground.
full_question: Members of this profession were often buried in hollowed-out trees rather than the ground. A device called the ngoni was first used by these people. While kidnapped, a man in this profession found that a rival king was invulnerable unless shot with an arrow tipped by a white rooster's nail. These people were seen in green feathered costumes by traveler (*) ibn Battuta. One of these people named Balla Fasseke was at Kirina as his king defeated the Soso kingdom of Sumanguru. The Mandinka term for these people is used less often than a French term of unknown origin which may mean "servant" or "one who shouts." For 10 points, name these people who preserved the Epic of Sundiata into the present day, the traditional oral historians and ritual musicians of West Africa.
first_sentence: Members of this profession were often buried in hollowed-out trees rather than the ground.
raw_answer: griots [or jeli; or jali; or gewel; prompt on poets; prompt on musicians; prompt on praise-singers; prompt on advisors]