Anoa, also known as dwarf buffalo and sapiutan, are two species of the genus Bubalus, placed within the subgenus Anoa and endemic to the island of Sulawesi in Indonesia: the mountain anoa (Bubalus quarlesi) and the lowland anoa (Bubalus depressicornis). Both live in undisturbed rainforest and are similar in appearance to miniature water buffaloes, weighing . Both species of anoa have been classified as endangered since the 1960s and the populations continue to decrease. Fewer than 5,000 animals of each species likely remain. Reasons for their decline include hunting for hides, horns and meat by the local peoples and loss of habitat due to the advancement of settlement. Currently, hunting is the more serious factor in most areas. Anoa are most closely allied to the larger Asian buffaloes, showing the same reversal of the direction of the hair on their backs. The horns are peculiar for their upright direction and comparative straightness, although they have the same triangular section as in other buffaloes. White spots are sometimes present below the eyes and there may be white markings on the legs and back; the absence or presence of these white markings may be indicative of distinct races. The horns of the cows are very small. The nearest allies of the anoa appear to be certain extinct Asian buffaloes, the remains of which have been found in the Siwalik Hills of northern India. Both are found on the island of Sulawesi and the nearby island of Buton in Indonesia. They apparently live singly or in pairs, rather than in herds like most cattle, except when the cows are about to give birth. Little is known about their life history as well. However, in captive individuals they have a life expectancy of 20–30 years. The anoa take two to three years before they reach sexual maturity and have one calf a year and have very rarely been seen to have more. Skulls of anoa cannot be accurately identified as to species, and there is likely hybridizing and interbreeding between the two in the zoo population. It is questioned as to whether the two species were actually different due to them occurring together in many different areas, as well as some interbreeding. A study of the mtDNA of ten specimens from different localities found a high mitochondrial genetic diversity between individuals identified as one or the other species, indicating support for recognition as two