Crest (feathers) Crest (feathers) The crest is a prominent feature exhibited by several bird and other dinosaur species on their heads. The crest is made up of semiplume feathers: a long rachis with barbs on either side. These are plumulaceous feathers, meaning that they are soft and bendable. In birds, these semiplumes are common along the head, neck, and upper back, and may be used for buoyancy and sensing vibrations. Crests on birds are generally used for display purposes. Cockatoos and their smaller cousins, cockatiels, are part of the parrot family Cacatuidae found in Australia, the Bismarck Archipelago and the Philippines, and
Calamus rotang plants. It has pinnate, alternate leaves, 60–80 cm long, armed with two rows of spines on the upper face. The plants are dioecious, and flowers are clustered in attractive inflorescences, enclosed by spiny spathes. The edible fruits are top-shaped, covered in shiny, reddish-brown imbricate scales, and exude an astringent red resin known medicinally and commercially as "Dragon's blood". The canes are sought-after and expensive, but have to a large extent been replaced by sticks made from plants, such as bamboos, rushes and osier willows. Calamus rotang Calamus rotang is a plant species native to India, Sri Lanka and Myanmar (Burma).