As a baby bird develops, its body contorts to fit within the confines of its egg . The bird's neck twists so that one side of its head is tucked against its chest. In this position, the bird's left eye remains nestled among sprouting feathers–where it does not receive much light from the outside world–whereas the right eye is pressed up against the eggshell, glimpsing flickers of light and shadow through a veil of calcium carbonate.
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Pirate-Eye Pigeons Reveal How the Brain Talks to Itself