Mythology is full of winged creatures, human and otherwise. The multitude of them across cultures would be quite baffling, if they weren't so common in reality. In fact, new classes of winged creatures are born nightly, and some only exist until the next daybreak. At night it is possible to see them perched on rooftops and in trees, especially in uninhabited areas. Winged creatures like buildings, but they don't care for humans. That is why industrial areas such as parts of West Oakland were once teeming with the nightly flutter of wings, like the sound of thousands of notebooks falling softly from the sky. Residential development has pushed the winged creatures further afield, but persistent, quiet observation can still yield results in Oakland too.