Horns and antlers always seem to accentuate an animal’s demeanour, mood or appearance. A confrontational buffalo bull staring through the foliage wouldn’t look anywhere near as intimidating without the sleek curvature of his cranial armour. A magnificent elk bull, high up on the ridge, calling into the early morning mist wouldn’t be quite so breath-taking without his rack of magnificent antlers.
Naturally, these head adornments tend to elicit a similar array of questions from many of our guests, one of which is, “Are Horns the same as Antlers?”.
Like horns, antlers are primarily used in the contest between males for territory, dominance and mating rights but there are, however, several telling differences between the two.
Antlers, characteristic of the Cervidae or deer family, are branching deciduous growths that are shed annually.
At anything from a ¼ to one inch per day, antler growth is one of the fastest types of growth tissue on Earth, and the only example of an organ that is shed and regrown each year. When antlers are growing they’re bulbous and pliable, composed of blood vessels, skin, cartilage and bone. The outermost layer of skin covering a growing antler is covered in tiny hairs, has a distinct velvety texture and is soft, warm and almost spongy to the touch. The ‘velvet’ increases the apparent size of the antlers, promotes bone development and acts similarly to an insect’s antennae, alerting the animal to anything they come into contact with. If an antler is cut or severed during the growth phase of the antler cycle the animal could bleed to death.
The antler cycle is driven by testosterone which in turn is triggered by increasing day length (Photoperiodism) in spring. At the beginning of summer after approximately 4 months of growth – depending on various environmental and biological factors – antlers reach their full size and the cartilage begins to calcify. By the end of summer, when testosterone levels are at their peak, the blood vessels shut down around the base of the antlers, the velvet layer dies and ‘peels’ off, and the antlers harden into some smooth and spectacular mammalian finery. Antler production, especially the internal synthesis of calcium (largely absent from their diet), draws heavily on the animal’s nutrient reserves and so they also act as a visual demonstration of the animal’s fitness. As winter nears, the level of testosterone decreases due to shortening day length and the antlers are shed.
Horns on the other hand, typical of most male members of the Bovidae family, are not shed nor are they branched but they do come in a spectacular array of curved, straight, twisted or spiralled shapes and sizes often with ridges or fluting along two thirds of their length. They have a solid bony core that grows from the frontal bones of the skull within a keratinous sheath that develops from external epidermal layers. Development begins soon after birth and like a fingernail, continues throughout their life. If horns are broken they may continue to grow in an irregular or deformed manner and deformities may also occur as a result of inbreeding, injuries or mineral deficiencies in the diet.
With the exception of Caribou and Reindeer (usually small and poorly formed), antlers usually never grow on females but horns can occur on both sexes. As a general rule of thumb, if it has horns then it’s a male. But in certain species, including Cape Buffalo and Blue Wildebeest, both sexes have horns.
Generally, in nomadic species or grazers (barring eland which are mixed feeders) both sexes will have horns whereas in species that prefer closed habitats and are either mixed feeders or browsers, only the males will have horns. Open-habitat species, such as Sable, Roan, Tsessebe and Gemsbok, usually form larger herds that are dominated by a single male. As a consequence, and due to the fact that there is less cover on which to rely, females require horns in the defence of their young. If horns were absent in females, predators with their propensity for picking out young, infirm or injured animals, would consistently target females resulting in a skewed sex ratio. Species that prefer closed-habitats, such as kudu, bushbuck, nyala and most duikers) generally occur in pairs or smaller family units (impala are the exception). The absence of horns facilitates movement through thicker vegetation and makes them less conspicuous. Males, however, still require horns in order to compete for females.
There’s certainly something awe-inspiring about a herd of fifteen kudu bulls chewing the cud in the shade of a large Knobthorn acacia on a hot summer’s day, their corkscrew shaped horns silhouetted against a bright grassy backdrop, a line of impala rams marching across the skyline at sundown or gazing over a herd of six hundred buffalo; black bodies, dung, flies and a field of bovine weaponry.
And it’s the horns that add the vibrancy, tweaks the saturation and draws out the clarity in an already picturesque setting.