Ossicone

An ossicone is a permanent, skin-covered bony projection on the head of giraffes and okapis. Unlike antlers, it remains covered by skin and does not shed.

Giraffe: A tall African ruminant with an exceptionally long neck and legs, belonging to the family Giraffidae. Giraffes bear paired ossicones whose shapes vary with age and sex.
Endochondral ossification: The process by which bone forms by replacing a cartilage model. Ossicones begin as cartilage and later become bony structures.
Antler: A branching bony structure grown and shed annually by members of the deer family. Antlers are shed, whereas ossicones persist throughout an animal’s life.
Giraffe age estimation: Methods for estimating a giraffe’s age from physical and developmental traits. Ossicone fusion and surface changes can indicate stages of giraffe development.
Okapi: A forest-dwelling African mammal and the only living relative of the giraffe. Okapis also develop ossicones, but typically only males do.
Dermis: The layer of skin beneath the epidermis, containing connective tissue, blood vessels, and nerves. Ossicones remain covered by skin rather than becoming exposed bone.
Horn: A permanent head structure typically consisting of a bony core covered by keratin. Typical horns have an exposed keratin sheath; ossicones remain skin-covered.
Giraffe sexual dimorphism: Differences in appearance between male and female giraffes, including traits of the head and neck. Ossicone shape and development can help distinguish adult males from females.
Giraffidae: The mammal family containing giraffes and okapis, the only living members of the group. Ossicones distinguish the living members of this family from other even-toed ungulates.
Frontal bone: A skull bone forming the forehead and the upper parts of the eye sockets. Giraffe ossicones fuse to the skull, including the frontal bones.

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