Task: Question Generation
Input (English): Passage: The IUCN currently recognises only one species of giraffe with nine subspecies. In 2001, a two-species taxonomy was proposed. A 2007 study on the genetics of Giraffa, suggested they were six species: the West African, Rothschild's, reticulated, Masai, Angolan, and South African giraffe. The study deduced from genetic differences in nuclear and mitochondrial DNA (mtDNA) that giraffes from these populations are reproductively isolated and rarely interbreed, though no natural obstacles block their mutual access. This includes adjacent populations of Rothschild's, reticulated, and Masai giraffes. The Masai giraffe was also suggested to consist of possibly two species separated by the Rift Valley.Reticulated and Masai giraffes have the highest mtDNA diversity, which is consistent with giraffes originating in eastern Africa. Populations further north are more closely related to the former, while those to the south are more related to the latter. Giraffes appear to select mates of the same coat type, which are imprinted on them as calves. The implications of these findings for the conservation of giraffes were summarised by David Brown, lead author of the study, who stated: "Lumping all giraffes into one species obscures the reality that some kinds of giraffe are on the brink. Some of these populations number only a few hundred individuals and need immediate protection."A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes. The eight species are: G. angolensis, G. antiquorum, G. camelopardalis, G. giraffa, G. peralta, G. reticulata, G. thornicrofti, and G. tippelskirchi.
Output (English): In what year was eight species of living giraffes described?