Do pigeons have a built in GPS?

Houston - Some new research has explored how pigeons find their way home. The findings suggest that pigeons have a type of in-built magnetic compass, something similar to a natural GPS.

Scientists have known for a several years that pigeons, and some other animals like mole rats, rely on Earth’s magnetic field for orientation and navigation. What has been unknown, until recently, is how animal and bird brains process this magnetic information and use it to navigate their way over long distances. The 'homing pigeon' is particularly adept at this. The science team was based at the Department of Neuroscience, Baylor College of Medicine, Houston. New research, published in the journal Science in April 2012, has identified the neural source of magnetic sense in pigeons. This relates to special cells that are able to ‘encode’ three key positioning factors. According to the research summary, these factors are: the direction of a magnetic field, its intensity, and its polarity (north or south). The cells have been shown to be iron-rich. According to The Guardian, the research has also shown that when pigeons are responding to magnetic fields as part of their famed homing ability, four areas of the brain become active, including the hippocampus, which is the site of spatial memory. This aspect of the research suggests that the birds’ home based on a combination of visual, vestibular (the system of balance and orientation), and auditory systems. The scientists have called this “magnetoreception”, where the birds have a type of in-built inclination-sensitive light-dependent compass. The research findings do not just relate to pigeons. The findings could explain how people interpret maps in their heads and may, at some future date, help clinicians treat individuals afflicted with spatial disorientation. The reference for the research paper is: L. Wu and J.D. Dickman. “Neural correlates of a magnetic sense,” Science.