The Components of Reindeer Antlers
Reindeer antlers are complex structures primarily composed of true bone tissue. This bone forms the hardened core of the antler. While antlers are solid bone when mature, their formation begins with a cartilaginous precursor that later transforms into bone.
During their growth phase, antlers are covered by a soft, vascularized skin called velvet. This velvet, a living tissue rich in blood vessels and nerves, supplies essential nutrients and oxygen for rapid bone formation. The velvet also contains hair follicles, giving it a fuzzy appearance.
The hard, mature antler is highly mineralized, containing calcium and phosphorus. These minerals contribute to the antler’s hardness and strength. Other trace minerals are also incorporated into the bone matrix during growth.
How Antlers Form and Develop
Reindeer antlers grow from specialized bony outgrowths on the skull called pedicles. These pedicles serve as the attachment points and the foundation for annual antler regeneration. The growth process is fast, making antlers one of the fastest growing tissues in the animal kingdom.
The velvet covering plays an important role in nourishing the developing antler as it grows. Blood vessels within the velvet deliver the necessary minerals and proteins, allowing the underlying cartilage to expand and then ossify, meaning it transforms into bone. This process of ossification proceeds from the base of the antler outwards towards the tips.
Once the antler reaches its full size, the velvet begins to dry and shed. This shedding process can take several weeks, revealing the hard, polished bone underneath. After the breeding season, usually in late winter or early spring, the mature antlers are shed, and the cycle begins anew from the pedicles.
Antlers Compared to Horns
Antlers and horns are often confused, but they have distinct compositions and growth patterns. Antlers, like those found on reindeer, are made of bone and are shed and regrown annually. This annual shedding is a feature that sets them apart from horns.
In contrast, horns, found on animals such as cattle, sheep, and goats, are permanent structures. They consist of a bony core that is covered by a sheath made of keratin, the same protein found in human fingernails and hair. Horns grow continuously throughout an animal’s life and are not shed.
Reindeer are unique among deer species because both males and females typically grow antlers. While male reindeer grow larger, more branched antlers, female reindeer also develop smaller antlers, which they often retain longer into the winter than males. This bilateral antler growth in both sexes is an unusual trait.