Day or night, trained pigeons can find their way home from distances of nearly 1,000 kilometers (about 600 miles). This remarkable skill has fascinated humans for centuries. Scientists have known for around a century that birds use magnetoreception—an ability to sense magnetic fields—for navigation.
A recent study from the University of Bonn and the Max Planck Institute of Animal Behavior highlighted a surprising new factor: the pigeons’ livers. This research, published in Science, reveals that superparamagnetic macrophages in the liver help pigeons navigate using magnetic fields.
Macrophages, a type of immune cell, can accumulate iron as they break down old red blood cells. This may enable them to respond to magnetic fields. The study showed that when these macrophages were depleted, pigeons struggled to navigate under overcast conditions. However, they still managed well when the sun was visible, demonstrating that they rely on multiple cues for orientation.
The lead researcher, Martin Wikelski, noted that the sensation of direction pigeons experience might have a physical basis linked to these immune cells. They are located near nerve cells in the liver, possibly transmitting information to the pigeons’ brains. “We didn’t expect immune cells to act like sensors for magnetic fields at all,” co-senior author Christian Kurts pointed out, revealing how this discovery uncovers a new mechanism of perception in animals.
Historically, pigeons have played a crucial role in communication. Ancient Greeks used them to deliver news of Olympic victories. The Romans enhanced military communication with a network of carrier pigeons. Even in modern times, pigeons were used by news agencies like Reuters in the mid-1800s to send stock prices quickly.
During WWI, pigeons were vital for relaying messages from front lines to command posts, often facing danger from enemy snipers. In WWII, the British military initiated Operation Columba, using thousands of pigeons to gather intelligence from occupied territories.
Today, pigeons are still involved in sports and companionship, drawing fans and breeders worldwide. They remind us of a time when connecting quickly was life and death, and their incredible navigation skills continue to intrigue scientists and animal lovers alike.
For more about this fascinating subject, you can check out the study on Science here.
