In one particularly memorable piece, "Composition 1960 55," Young released a flock of butterflies on the audience and they listened to the beat of their wings.
Rather than crashing into us, they flew around us, like water parting around a rock in a stream, and the sound of their wings beating was like a roar of moving air that was almost on the edge of hearing.
The only sound was the whoosh of their wings beating against the air.
However, as in the largest present-day birds, Pteranodon's large size precluded sustained beating of the wings, so it most likely soared more than it flapped.
To him, they are alive — but also dying, because they are destined to be burned: "Unbidden, an image rises to his mind: a folder, fallen open, spilling out not paper, not some poor soul's forsaken manuscript, but birds, hundreds of birds beating their wings furiously, desperate to find their way out of the incinerator, bursting into flames".
They function in the regulation of such movements as the beating of wings in locusts.
With a fierce beating of wings, the butterfly has finally escaped her chrysalis and taken flight.
But as I lie here I can distinctly hear the beating of wings of the angel of death.
But the dead only fed the living, and each morning when the people woke it was to the scraping and beating of wings, the murmurous susurration, the awful cooing babble, and the sight of the curious and gentle faces of those creatures.
The air is awash with flashes of light, darting, landing or beating their wings as they refresh with nectar.
