... includes using celestial cues in combination with an internal clock, geomagnetic cues such as magnetic intensity or perhaps even olfactory cues. Presently, there is not enough evidence to rule out any of these, and years of studying birds in a laboratory setting have yielded partly contradictory results...

... of other long-distance ocean navigators. An unusual pattern of magnetic anomalies exists on the ocean bottom in seafloor-spreading zones (areas where continental plates diverge). As the plates move apart, molten material continually seeps out along the ocean floor and, as it cools, acquires magnetization...

...Kenneth J. Lohmann; Catherine M. F. Lohmann; Nathan F. Putman SUMMARY Diverse animals detect the Earth's magnetic field and use it as a cue in orientation and navigation. Most research on magnetoreception has focused on the directional or `compass' information that can be extracted from the Earth's...

...John H. Wang; Shaun D. Cain; Kenneth J. Lohmann SUMMARY Diverse animals use the Earth's magnetic field as an orientation cue, but little is known about the sensory, processing and motor elements of the neural circuitry underlying magnetic orientation behavior. The marine mollusc Tritonia diomedea...

... caretta L., captured turtles were tethered in a water-filled arena located outdoors. Turtles tested under these conditions established and maintained headings in specific directions in the absence of wave cues, familiar landmarks and chemical gradients. Distorting the magnetic field around the anterior...

...John H. Wang; Shaun D. Cain; Kenneth J. Lohmann SUMMARY Behavioral experiments have demonstrated that the marine mollusc Tritonia diomedea can use the Earth's magnetic field as an orientation cue. Little is known, however, about the neural mechanisms that underlie magnetic orientation behavior...

..., turtles initially orient seawards by swimming into waves, which can be detected as orbital movements from under water. Laboratory experiments have demonstrated that turtles can transfer a course initiated on the basis of waves or visual cues to a course mediated by a magnetic compass. Thus, by setting...

... environment. Relatively little is known, however, about the orientation cues that lobsters use to guide their movements. To determine whether lobsters can orient to the earth’s magnetic field, divers monitored the orientation of lobsters tethered inside magnetic coil systems submerged offshore in the Florida...

...Kenneth J. Lohmann; Catherine M. F. Lohmann ABSTRACT For animals that migrate long distances, the magnetic field of the earth provides not only a possible cue for compass orientation, but a potential source of world-wide positional information. At each location on the globe, the geomagnetic field...

... hatchlings can orient using the earth’s magnetic field. For the magnetic compass to function in guiding the offshore migration, however, hatchlings must inherit or acquire a magnetic directional preference that reliably leads them towards the open sea. On land, hatchlings find the ocean using light cues...

...Phillip Light; Michael Salmon; Kenneth J. Lohmann ABSTRACT Recent experiments have demonstrated that hatchling loggerhead sea turtles can orient using the earth’s magnetic field. To investigate the functional characteristics of the loggerhead magnetic compass, we tested the orientation...

...Kenneth J. Lohmann ABSTRACT Laboratory experiments were conducted to test the ability of loggerhead sea turtle hatchlings (Caretta caretta L.) to orient using the magnetic field of the earth. Hatchlings were tethered to a rotatable lever-arm apparatus which tracked swimming orientation in complete...

... amplitudes and time scales ( Skiles, 1985 ). Our results are consistent also with the possibility that honeybees use the geomagnetic field for navigation, as has been suggested for homing pigeons ( Keeton, 1972 ). The technique of attaching magnetic wires to individual bees permits impairment experiments...

...Robert C. Beason; William J. Brennan ABSTRACT The magnetic characteristics of the heads from 28 bobolinks [Icteridae: Dolichonyx oryzivorus (L.)] were analysed using remanence magnetometers. The natural remanent magnetization of 12 freshly preserved heads averaged 3·20×10 −7 electromagnetic units...

...Darci Motta S. Esquivel; Henrique G. P. Lins De Barros ABSTRACT Magnetic moments for different magnetotactic microorganisms are obtained by electron microscopic analyses and studies of cell motion by optical microscopy. The results are analysed in terms of a model due to C. Bean. The considerations...

...Kenneth J. Lohmann ABSTRACT The magnetic characteristics of 15 western Atlantic spiny lobsters (Panulirus argus) were analysed with a superconducting cryogenic magnetometer. Each specimen possessed a significant natural remanent magnetization (NRM) and isothermal remanent magnetization (IRM...