Bald eagles are not actually bald. Their name comes from an old English word meaning "white-headed."

The bald eagle (Haliaeetus leucocephalus) derives its common name from the Middle English word 'balde,' which historically meant white or shining rather than hairless. This naming convention is also seen in other species like the 'piebald' horse, which features white patches. Taxonomically, the species name 'leucocephalus' is Greek for 'white head,' further confirming the intended description of the bird's appearance.Young bald eagles go through several plumage stages before reaching their final adult look. For the first four to five years of their lives, they are primarily brown with varying amounts of white mottling on their wings and underparts. This juvenile coloring serves as a form of camouflage and signals to territorial adults that the younger bird is not yet a reproductive rival.The transition to a pure white head and tail is driven by hormonal changes as the bird reaches sexual maturity. Research from the Cornell Lab of Ornithology indicates that this distinct contrast helps eagles identify potential mates from a distance. By age five, the beak also transitions from a dark gray to a bright yellow, completing the transformation.Bald eagles were chosen as the national emblem of the United States in 1782 due to their majestic appearance and longevity. In the wild, these birds can live for 20 to 30 years, though the oldest recorded banded eagle lived to be 38. Their unique coloring remains one of the most successful evolutionary traits for social signaling within the species.