RESUMEN
Elegant new experiments show that migrant birds at high European latitudes can use magnetic declination to infer longitude.
Asunto(s)
Passeriformes , Pájaros Cantores , Migración Animal , Animales , Magnetismo , OrientaciónRESUMEN
New 'virtual displacement' experiments demonstrate that migrating reed warblers know the magnetic coordinates of their destination, and can set a novel course to their goal with only magnetic-field parameters as a guide.
Asunto(s)
Migración Animal , Fenómenos Magnéticos , Orientación , Pájaros Cantores/fisiología , Navegación Espacial , AnimalesRESUMEN
Sea turtles memorize the magnetic coordinates of their natal beach, returning to that combination of parameters to lay eggs decades later. The intervening secular (year-to-year) variation in field intensity and inclination can lead the nesting females to a series of predictably different beaches.
Asunto(s)
Fenómenos de Retorno al Lugar Habitual/fisiología , Fenómenos Magnéticos , Navegación Espacial/fisiología , Tortugas/fisiología , AnimalesRESUMEN
Before migrating from their home streams to the ocean, young Pacific salmon already know the magnetic parameters of their feeding grounds, allowing them to steer into a favorable habitat. What kind of 'map' representation underlies this remarkable ability?
Asunto(s)
Migración Animal , Fenómenos Magnéticos , Salmón/fisiología , AnimalesRESUMEN
Elegant new experiments show that on clear nights and in the absence of other celestial cues, dung beetles can orient their routes to the band of stars known as the Milky Way.
Asunto(s)
Migración Animal/fisiología , Impronta Psicológica , Campos Magnéticos , Salmón/fisiología , AnimalesRESUMEN
Newly hatched sea turtles exposed to artificially generated magnetic fields with parameters characteristic of two sites 3700 km apart, differing only in longitude, can distinguish the two apparent locations and orient appropriately.
Asunto(s)
Migración Animal , Geografía , Magnetismo , Orientación/fisiología , Tortugas/fisiología , AnimalesRESUMEN
Few subjects in animal behavior have more exotic mystery than magnetic-field sensitivity. A force we cannot sense, generated by events no one completely understands, creates field lines that pass through our bodies without any evident effect on us or on them. It is an energy felt as much by migrating lobsters on the sea floor as by ocean-crossing birds thousands of meters overhead, transduced in generally poorly understood ways. Despite the blindness of humans, modern life depends on this invisible, ghostlike field. Aside from lights and heaters, nearly every electrical device we own makes use of electromagnetism, and that same magnetism is essential in generating the power these new-found necessities consume. But for many animals, the reliance is far older and more basic: their life-or-death ability to find their way around in the world depends on correctly interpreting the earth's magnetic field.
Asunto(s)
Fenómenos Electromagnéticos , Percepción , Sensación , Animales , Óxido Ferrosoférrico/químicaRESUMEN
Many animals seem to know their location even when far from home. Evidence variously implicates odors or magnetic fields. The most consistent olfactory results, however, may not mean what we think.
Asunto(s)
Columbidae/fisiología , Fenómenos de Retorno al Lugar Habitual/fisiología , Orientación , Olfato/fisiología , Percepción Espacial/fisiología , Animales , Conducta Animal , Vuelo Animal , Magnetismo , OdorantesRESUMEN
Animals have several types of magnetic organ, often separately specialized for determining direction versus location. Recent results offer hints about how these once-unimaginable detectors may have evolved.
Asunto(s)
Evolución Biológica , Óxido Ferrosoférrico , Magnetismo , Orientación/fisiología , Animales , Luz , Pájaros Cantores/fisiologíaRESUMEN
Determining longitude is incredibly difficult--for humans. Are animals fooling us into thinking that they have bicoordinate maps? New experiments show that at least some creatures effortlessly solve the seemingly insoluble problem of longitude.
Asunto(s)
Migración Animal/fisiología , Columbidae/fisiología , Percepción/fisiología , Animales , Humanos , Magnetismo , Pájaros Cantores/fisiologíaRESUMEN
When flying in pairs, pigeons with different preferred paths back to the loft often agree on a joint route, and in doing so get home faster than either would have done on its own.
Asunto(s)
Columbidae/fisiología , Vuelo Animal , Fenómenos de Retorno al Lugar Habitual , Conducta Social , Predominio Social , Animales , Toma de DecisionesRESUMEN
A recent study has found that sparrows moved gradually east above the Arctic Circle completely altered their migration strategy after encountering the massive natural change in declination near the magnetic pole. This should not happen--or should it?