Rhinoceros are killed bi humans for thair horns, which are boucht an sauld on the black mercat, an which are uised bi some culturs for ornamental or tradeetional medicinal purposes. East Asie, specifically Vietnam, is the lairgest mercat for rhino horns. Rhino horns cost as much as gowd on the black mercat. Fowk grind up the horns an then consume them believin the dust haes therapeutic properties. The horns are made o keratin, the same teep o protein that maks up hair an fingernails. Baith African species an the Sumatran rhinoceros hae twa horns, while the Indian an Javan rhinoceros hae a single horn.