Bull Elk Bugling | Up Close & Personal | Yellowstone National Park 🦌

An elk’s antlers – which only grow on bulls – don’t just look cool. They’re made of fast-growing bone. How fast? Well, they’ve been known to grow as much as one inch in one day. This rapid pace has led some scientists to suggest that studying elk’s antlers might give us some help in the fight against certain types of cancer in humans. The size of an elk’s antlers depends on the amount of sunlight the elk gets; sunlight causes a boost in testosterone levels, causing the antlers to grow. They can weigh as much as 40 pounds in a full grown male.