 Additional features such as shade, waterproof roof, "pillow", and "blanket", all of which are made from branches, twigs and leaves, may also be added.Nest-building in primates is considered as an example of tool use and not animal architecture.The Bornean orangutan diet is composed of over 400 types of food, including wild figs, durians ("Durio zibethinus" and "D. graveolens"), leaves, seeds, bird eggs, flowers, honey, insects, and, to a lesser extent than the Sumatran orangutan, bark.