• They do. Here is an excerpt from a longer text on the topic, taken from : Antler Development In most of the whitetails range, antler growth usually begins during the months of March or April, by August or early September, antlers are fully-grown. Deer antlers are among the fastest growing tissues known to man. Growing at an average of 1 to 2 inches per week. Growing antlers are covered with a living tissue called velvet. During development, the deer's antlers are very delicate. This is the time when most antler damage or breakage occurs. Velvet is shed or rubbed off by the buck as he rubs small trees with his antlers. After the breeding season, bucks will shed their antlers. Antlers are usually shed in January or February. Antler shedding usually occurs earlier in northern states than southern states. A new pair of antlers will start growing in the spring. Antlers Antler growth in bucks begins when they are fawns. However, buck fawns grow antlers larger than short "buttons," or pedicles, which on occasion become hardened. These pedicles then develop into the buck's first spike or branched antlers, when he is a yearling (1 1/2 years old). Antler size then continues to increase each additional year until peaking generally at age 6 1/2 or 7 1/2. Bucks begin growing their antlers in late-winter or early spring, within weeks of when the previous year's antlers are shed. Antlers grow very slowly at first, but by late-May, antlers are rapidly growing. Antler growth is usually complete by the end of August. The velvet then hardens and falls off during September. The hardened, polished antlers remain until they are shed during December through April, depending on location and management practices. Why Are There Annual Cycles In Antler Growth? Believe it or not, the 23 degree tilt of the Earth's axis is the ultimate cause for the annual cycles in deer antlers. This tilt is what causes Earth's annually recurring seasons. Deer have adapted their physiology and behavior to these seasonal changes, including antler growth. The environmental cue that regulates antler growth is the amount of day length, or photoperiod. The physiological cue is the male hormone testosterone. The way this works is complicated, but changing day lengths are sensed by the eyes, which send this message, via the optic nerve, to the pineal gland. The pineal gland - a pea-sized organ at the base of the brain - produces many different hormones. One hormone produced is luteinizing hormone, which controls the amount of testosterone produced in the testes. The antler cycle lags behind the changes in day length because the hormonal changes take time. During fall, decreasing day lengths cause melatonin production to increase, resulting in decreased production of both luteinizing hormone and testosterone. Decreasing testosterone levels then cause the antlers to shed. Antler Shedding Antlers are shed when a thin layer of tissue destruction, called the abscission layer, forms between the antler and the pedicle. This layer forms as a result of the decrease in testosterone. As the connective tissue is dissolved, the antler loosens and is either broken free, or falls off on its own. This degeneration of the bone-to-bone bond between the antler and the pedicle is the fastest deterioration of living tissue known in the animal kingdom. In whitetails, a restricted diet has been found to cause bucks to shed their antlers early. It has been suspected that the lack of adequate nutrition somehow affects testosterone output. Nutritionally-stressed bucks may also grow their antlers and shed their velvet later. Older-aged bucks are thought to shed their antlers earlier than younger bucks. It has also been reported that higher-ranked (more dominant) bucks cast their antlers sooner than lower-ranked (subordinate) bucks. Older-aged, more dominant bucks probably shed their antlers sooner because of the high energy costs incurred in maintaining a higher dominance rank. The farther deer are from the equator, the more defined their antler cycle. In other words, northern deer have a shorter "window" of when antler shedding can occur, compared to deer herds in southern states. In addition, the specific date when a buck will shed his antlers may be determined more by his individual antler cycle than any other factor. This cycle is independent of other bucks and is believed to be centered on each animal's birth date. Penned deer studies have allowed scientists to measure the exact dates of antler shedding for individual deer year after year. One study in Mississippi found that individual bucks usually shed their antlers at the same time each year and almost always during the same week. Yearling bucks with only spike antlers shed sooner than yearling bucks with forked antlers, likely because they were more nutritionally stressed than fork-antlered bucks. This study also indicated there was no relationship between antler mass and date of antler shedding, although other studies have shown that bucks shed their antlers earlier as they grow older. Additional penned studies have also revealed that bucks usually shed both antlers within three days of each other. Although there is no clear evidence that weather directly affects antler shedding, it is likely that severe winters may also cause bucks to shed their antlers earlier than normal because of the nutritional stress this causes.

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