Researchers have discovered that pigeons might possess a unique "compass" located within their livers. A team from the Max Planck Institute of Animal Behavior, alongside the University of Bonn, has identified that liver macrophages—immune cells responsible for recycling aging red blood cells—accumulate iron. This iron endows the cells with magnetic properties, potentially enabling the birds to detect the Earth's magnetic field.
To investigate this phenomenon, the scientists extracted these iron-rich cells from homing pigeons before releasing them over 20 kilometers away from their home. On clear days, the pigeons successfully navigated back, likely relying on the sun for guidance. However, on overcast days, the birds lacking these specialized cells struggled significantly to find their way home.
The researchers posit that the liver may play a crucial role in the avian sensory system. The iron nanoparticles within these macrophages can interact with the magnetic field, and nearby nerve fibers may be capable of transmitting this information to the brain. Would you prefer to navigate using your liver? Not the most practical option, but it seems some might humorously claim they do!
Informational material. 18+.