查看文章

Understanding the molecular and cellular mechanisms that mediate magnetosensation in vertebrates is a formidable scientific problem^,. One hypothesis is that magnetic information is transduced into neuronal impulses by using a magnetite-based magnetoreceptor^,. Previous studies claim to have identified a magnetic sense system in the pigeon, common to avian species, which consists of magnetite-containing trigeminal afferents located at six specific loci in the rostral subepidermis of the beak^,,,. These studies have been widely accepted in the field and heavily relied upon by both behavioural biologists and physicists^,,. Here we show that clusters of iron-rich cells in the rostro-medial upper beak of the pigeon Columbia livia are macrophages, not magnetosensitive neurons. Our systematic characterization of the pigeon upper beak identified iron-rich cells in the stratum laxum of the subepidermis, the basal region of …