Antlers may look like an accessory, but they’re actually weapons. Males of the deer family—moose, deer, elk, and reindeer, to name a few—grow the large, bony structures to scare away (or in severe cases, fight off) romantic rivals trying to woo their mates. In the video above, created by YouTube video series Deep Look, host and writer Amy Standen explains how the animals grow the massive appendages, and why they need to sprout new ones each year.

[h/t The Kid Should See This]

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