We often think of quantum mechanics as only affecting only the smallest scales of reality, with classical reality taking over at some intermediate level. But in his 1944 book, What is Life?, the quantum physicist Erwin Schrödinger suggested that “incredibly small groups of atoms, much too small to display exact statistical laws, do play a dominating role in the very orderly and lawful events within a living organism.” Schrodinger was a visionary - and perhaps very specifically in this case. Because it turns out we might need all the weirdness of quantum mechanics to explain birds.