Flag of Zanzibar yellow cloves was added to the flag. On 12 January 1964, John Okello overthrew the Sultan of Zanzibar and adopted a black-yellow-blue tricolour as the flag of the People's Republic of Zanzibar and Pemba. On 29 January, the country's flag was changed to a blue-black-green tricolour with a thin white stripe at the hoist. This design, which was based on the flag of the Afro-Shirazi Party, was the longest-lived of the post-independence flags and eventually formed the basis for the current flag. On 26 April 1964, Zanzibar united with Tanganyika to form the new country of Tanzania and Zanzibar's old
Zanzibar in July. The main island of Zanzibar, Unguja, has a fauna reflecting its connection to the African mainland during the last Ice Age. Endemic mammals with continental relatives include the Zanzibar red colobus ("Procolobus kirkii"), one of Africa's rarest primates, with perhaps only 1,500 existing. Isolated on this island for at least 1,000 years, this colobus is recognized as a distinct species, with different coat patterns, calls, and food habits from related colobus species on the mainland. The Zanzibar red colobus lives in a wide variety of drier areas of coastal thickets and coral rag scrub, as well as mangrove