Pigeons have a 'compass' in their brains Credit: Alan D. Wilson, www.naturespicsonline.com WACO, Texas, April 26 (UPI) -- Pigeons navigate by recording information about Earth's magnetic field, using certain brain cells as a sort of biological compass, U.S. scientists say. The finding gives insight into how many birds can migrate thousands of miles, flying day and night, even when the sun or stars are obscured by clouds, the researchers said. Two researchers at Baylor College of Medicine have solved a central part of the mystery of how the birds accomplish such feats, identifying specific cells in a pigeon's brain responsible for sensing and orienting the magnetic field. Researchers Le-Qing Wu and David Dickman identified a group of cells, or neurons, in the brain stem of pigeons that record both the direction and the strength of the magnetic field, The New York Times reported Thursday. Wu and Dickman found the birds' orientation determined which neurons were active, as each neuron was tuned to respond to signals from one direction while also registering the strength of the magnetic field. The researchers say there is evidence the information the cells are recording is coming from the inner ear, but that "is still something we want to pursue," Dickman said.