How homing pigeons navigate hundreds of kilometres and still find\ntheir way home has baffled scientists for decades. A recent study\npublished in the journal Science has now revealed a surprising answer:\nthe internal navigation system is located in the heart.<\/p>\n
Researchers discovered that pigeons use specialised immune cells in\ntheir liver called macrophages. These cells collect iron while breaking\ndown old red blood cells. The iron content gives the macrophages unique\nmagnetic properties, allowing them to respond to Earth\u2019s magnetic field\nand function as a natural compass.<\/p>\n
\u2018We never suspected immune cells could act as sensors for magnetic\nfields. Our research uncovered a previously unknown mechanism for animal\nmagnetoreception,\u2019 said Professor Christian Kurts, Director of the\nInstitute of Experimental Immunology and Molecular Medicine at Bonn\nUniversity Hospital, one of the lead authors of the study.<\/p>\n
\u2018What appears to be a \u2019gut feeling\u2019 in bird navigation may actually\nhave a physical basis,\u2019 added Professor Martin Wikelski, Director of the\nMax Planck Institute for Animal Behaviour and another lead author.<\/p>\n
To test the theory, a joint team of German universities tested\ntrained homing pigeons released from over 20 kilometres away. Scientists\nremoved the liver macrophages and monitored their flying ability.<\/p>\n
The results depended heavily on weather. On cloudy days when the sun\nwas hidden, pigeons without liver macrophages became disoriented and\nstruggled to return home. Conversely, on sunny days, they successfully\nnavigated back by relying on the sun rather than Earth\u2019s magnetic\nfield.<\/p>\n
The research also revealed how magnetic signals are transmitted to\nthe brain. Using electron microscopy, scientists detected that iron-rich\nmacrophages are positioned very close to nerve fibres. This proximity\nprovides a potential pathway for magnetic information to be transmitted\nfrom the liver to the central nervous system.<\/p>\n
\u2018This finding provides the first concrete evidence of how Earth\u2019s\nmagnetic field can be sensed within the body and relayed to the brain to\nguide movement,\u2019 said Dr Clivia Lisowski, the study\u2019s first author from\nBonn University.<\/p>\n
The remarkable discovery unites various known biological processes,\nfrom iron metabolism to communication between the immune and nervous\nsystems.<\/p>\n
\u2018Animal navigation is one of nature\u2019s most fascinating phenomena,\u2019\nsaid Wikelski. \u2018If immune cells are part of how birds sense direction,\nit will fundamentally change how we understand navigation.\u2019<\/p>\n
Researchers added that this discovery opens the possibility of\nsimilar mechanisms in other species. Sharks, known for effective\nnavigation without relying on light, are suspected to have a similar\nsensory system. There is even a possibility humans may respond to\nmagnetic fields in ways not yet fully understood.<\/p>", "url": "https:\/\/jawawa.id\/newsitem\/pigeons-natural-compass-found-in-heart-not-beak-or-eyes-1780298281", "image": "" }, "sponsor": "Okusi Associates", "sponsor_url": "https:\/\/okusiassociates.com" }