Who wrote the rule

Who wrote the rule that said a thing with feathers absolutely has to fly? (Fly? Why must they fly?) Some creatures have two wings that flap but you won't find them up there in the sky (Try, try, try, they're not up there in the sky) [PRE-Chorus] Gravity, they don't defy, they'll never soar, won't even try Well... [Chorus] Have you heard? (Have you heard?) About the flightless bird? (About the flightless bird?) With wings that flap, they've been supplied But after that, things went awry Well, have you heard? (Have you heard?) About the flightless bird? (About the flightless bird?) They're quite content, they're on the ground To see them don't look up, look down Clipse 'Chains & Whips' Lyrics & Meaning | Genius Verified [BRIDGE] Ostrich, kiwi, penguin, emu They all can't fly Let's play a little kazoo! [VERSE] Penguins swim where it's all frozen For flying, they've not been chosen Ostriches are fast as lightning Do they fly? (Who, us? Too frightening.) See the emu from Australia and the great New Zealand kiwi (Some birds were born to fly, but I just gotta be me! We won't cry, we won't frown We're happy right here on the ground!) [PRE-Chorus] Gravity, we won't defy, we'll never soar, won't even try Well... [Chorus] Have you heard? (Have you heard?) About the flightless bird? (About the flightless bird?) With wings that flap, they've been supplied But after that, things went awry Well, have you heard? (Have you heard?) About the flightless bird? (About the flightless bird?) They're quite content, they're on the ground To see them, don't look up. Look down