The ancestors of deer had tusks long upper canine teeth. In most species, antlers appear to replace tusks.
However, one modern species the comerțul cu vânătoare de elani deer has tusks and no antlers and the muntjac has small antlers and tusks. The musk deerwhich are not true cervids, also bear tusks in place of antlers. Only reindeer known as caribou in North America have antlers on the females, and these are normally smaller than those of the males. Nevertheless, fertile does from other species of deer have the capacity to produce antlers on occasion, usually due to increased testosterone levels.
Velvet covers a growing antler, providing blood flow that supplies oxygen and nutrients. Each antler grows from an attachment point on the skull called a pedicle.
While an antler is growing, it is covered with highly vascular skin called velvet, which supplies oxygen and nutrients to the growing bone. Once the antler has achieved its full size, the velvet is lost and the antler's bone dies. This dead bone structure is the comerțul cu vânătoare de elani antler.
In most cases, the bone at the base is destroyed by osteoclasts and the antlers fall off at some point. Although the antlers are regrown each year, their size varies with the age of the animal in many species, increasing annually over several years before reaching maximum size. In tropical species, antlers may be shed at any time of year, and in some species such as the sambarantlers are shed at different times in the year depending on multiple factors.
Some equatorial deer never shed their antlers.
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Antlers function as weapons in combats between males, which sometimes cause serious wounds, and as dominance and sexual displays. First, they can compete behaviorally where males use their antlers as weapons to compete for access to mates; second, they can compete physiologically where males present their antlers to display their strength and fertility competitiveness to compete for access to mates.
Despite this, a year study showed no shift in the median size of antlers in a population of red deer. Protection against predation[ edit ] If antlers functioned only in male—male competition for mates, the best evolutionary strategy would be to shed them immediately after the rutting season, both to free the male from a heavy encumbrance and to give him more time to regrow a larger new pair.
Yet antlers are commonly retained through the winter and into the spring,  suggesting that they have another use. Wolves in Yellowstone National Park are 3.
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These findings suggest that antlers have a secondary function in deterring predation. Snow shoveling for feeding[ edit ] Reindeer Kebnekaise valley, Sweden Reindeer genus Rangifer, whose sole member species R. This is one possible reason that females of this species evolved antlers.
Males shed their antlers prior to winter, while female antlers are retained throughout winter. Equipped with large, highly adjustable external ears, moose have highly sensitive hearing.
Moose with antlers have more sensitive hearing than moose without, and a study of trophy antlers with an artificial ear confirmed that the large flattened palmate antler behaves like a parabolic reflector.