Antlers are costly theater. Each autumn, bull elk turn freshly grown bone into contests for breeding access, shoving and sizing up rivals while the rack remains a disposable organ. One clash can decide. By displaying wide, branching bone before contact, each animal can judge risk without a ruinous struggle. Sexual selection rewards males that win contests or deter them, even when the prize will later fall from the skull.
Waste is the point. A large rack advertises condition because rapid skeletal growth drains protein, minerals, and energy, making size an imperfect but useful proxy for health, age, and competitive capacity. It is not cheap. Antlerogenesis draws heavily on calcium and phosphorus, while velvet supplies blood vessels and nerves to bone growing at remarkable speed. Rivals read it fast. Combat then sorts claims, since pushing matches can expose stamina, body mass, skill, and a male's willingness to absorb injury.
Shedding is not failure. When breeding season closes, a drop in testosterone activates osteoclast-mediated resorption at the antler base, loosening the structure until it is cast. Then comes velvet. Under rising hormones, stem cells in the pedicle rebuild the rack and erase much old damage, replacing a battered billboard with new bone before the next contest. Not permanence but turnover makes the animal's argument: strength must be demonstrated again, and the forest keeps no receipts.
