
Liver-Based Quantum Compass May Guide Pigeons Home
German researchers provide evidence that iron-rich macrophages in pigeons' livers may possess superparamagnetism and act as a liver-based quantum compass to help navigation, particularly when the Sun is obscured; experiments using clodronate to wipe these immune cells disrupted homing on overcast days, while normal navigation returned under sunny conditions, implying a liver-to-brain signaling pathway.
