They are made of solid bone and grow from a bony base on the skull. Antlers begin growing in the spring as skin-covered projections. When the antlers reach full size, the velvet dies and is rubbed off. The antlers are used in combat by males during the breeding season, and drop off afterwards. Antlers vary from simple spikes to enormous, branched structures.
All bovids have horns , at least in males and often in females.
Horns can vary from simple spikes to extremely long, curved structures - but always unbranched. Bovid horns are made up of a permanent bony core covered with a layer of keratin, which is never shed. The horn picture above shows the hollow area where the bony core would be found. Scoring criteria Study these two websites and write at least one paragraph describing how a rhinoceros horn is different from a cow horn . Study the webpage for each of the following mammals.