‘Mind-blowing’: Iron-rich immune cells help homing pigeons navigate | Science | AAAS

Of all the myriad animal senses, the most mysterious and controversial is the perception of magnetism. Somehow, migratory songbirds, sea turtles, and other creatures detect Earth’s magnetic field and use its directionality to help them navigate. Now, a paper published in Science has found a surprising mechanism: Iron-rich immune cells within homing pigeons’ livers seem to give the birds their magnetic compass. “The concept … is just mind-blowing,” says Catherine Lohmann, a sensory ecologist at the University of North Carolina at Chapel Hill who was not involved. “It’s truly a new direction and a very fresh take on a controversy that’s been in the literature for a long time.” Many animals have magnetically informed senses of direction, including birds, turtles, sharks, and dogs. A few researchers even think humans might have a vestigial magnetic sense. Exactly how this sense works has been hotly debated. An early hypothesis was that minute crystals of magnetite embedded within the anima

Of all the myriad animal senses, the most mysterious and controversial is the perception of magnetism. Somehow, migratory songbirds, sea turtles, and other creatures detect Earth’s magnetic field and use its directionality to help them navigate. Now, a paper published in Science has found a surprising mechanism: Iron-rich immune cells within homing pigeons’ livers seem to give the birds their magnetic compass. “The concept … is just mind-blowing,” says Catherine Lohmann, a sensory ecologist at the University of North Carolina at Chapel Hill who was not involved. “It’s truly a new direction and