Sumatran Orangutan

The Sumatran orangutan (Pongo abelii) is one of the three species of orangutans. Critically endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recently identified Tapanuli orangutan, also found in Sumatra. == Description == Male Sumatran orangutans grow to about 1.7 m (5.6 ft) tall and 90 kg (200 lb), while females are smaller, averaging 90 cm (3.0 ft) and 45 kg (99 lb). Compared to the Bornean species, Sumatran orangutans are thinner and have longer faces; their hair is longer and has a paler red color. == Evolution == Fossil orangutans in Sumatra from the Pleistocene had similar diets to present day Sumatran orangutans, consisting mainly of soft fruit as evidenced by dental microwear. == Behaviour and ecology == Compared with the Bornean orangutan, the Sumatran orangutan tends to be more frugivorous and especially insectivorous. Preferred fruits include figs and jackfruits. It will also eat bird eggs and small vertebrates. Sumatran orangutans spend far less time feeding on the inner bark of trees. Wild Sumatran orangutans in the Suaq Balimbing swamp have been observed using tools. An orangutan will break off a tree…