A family of small birds without visible feet, commonly called swiftlets and swifts.
The scientific taxonomic name combining 'apod-' (footless) + the Latin '-idae' suffix used for animal families. Named for their characteristic barely visible feet and leg feathers.
Swifts are so adapted to life in the air that their feet are tiny and hidden in feathers—they literally can't perch like other birds, so they've earned the name 'footless family' in taxonomy!
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