... and the output of the magnetic compass compared to the ... Gyroscopes, *Navigation reference, Computer applications, Calibration, Errors, Orientation ...
DTIC Science & Technology
The homing behavior of pigeons at the magnetic equator, where the field lines are horizontal, should provide either no magnetic compass or, an axial compass with a 180 deg ambiguity was observed. Pigeons released near noon were deprived of their Sun compa...
National Technical Information Service (NTIS)
Several studies have suggested that the magnetic compass of birds is located only in the right eye. However, here we show that night-migrating garden warblers (Sylvia borin) are able to perform magnetic compass orientation with both eyes open, with only the left eye open and with only the right ...
PubMed Central
Electric currents in the earth's interior give the earth an extensive magnetic field, which we detect from the orientation of compass needles.
NSDL National Science Digital Library
Arising from W. Wiltschko et al. 419, 467-470 (2002); Wiltschko et al. replyThe magnetic compass of migratory birds is embedded in the visual system and it has been reported by Wiltschko et al. that European Robins, Erithacus rubecula, cannot show magnetic compass orientation using their left ...
PubMed
... used for magnetic compass calibration on aircraft. ... for the new compass rose. ... Descriptors : *GEOMAGNETISM, COMPASSES, MAGNETOMETERS. ...
the earth's magnetic field for orientation and navigation (Sinsch 2006). The use of the geomagnetic fieldUse of a Magnetic Compass for Nocturnal Homing Orientation in the Palmate Newt, Lissotriton Heidelberg, pp. 151--203; Sinsch, U. 2006: Orientation and navigation in ...
E-print Network
The orientation system of the Savannah sparrow (Passerculus sandwichensis) is typical of nocturnal migrant passerine birds. It is based on a system of interacting compass senses: magnetic, star, polarized light and, perhaps, sun compasses. The magnetic compass capability ...
To investigate the relative importance of stellar and magnetic cues for the compass orientation of night migrating birds, 45 European robins (Erithacus rubecula) were tested in automatically registering cages with view of the clear natural night sky. One group was tested in the natural local geomagnetic field, the other group in a ...
The use of magnetic information for orientation and navigation is a widespread phenomenon in animals. In contrast to navigational systems in vertebrates, our understanding of the mechanisms underlying the insect magnetic perception and use of the information is at an early stage. Some insects use ma...
Technology Transfer Automated Retrieval System (TEKTRAN)
The orientation system of migratory birds consists of a magnetic compass and compasses based upon celestial cues. In many places, magnetic compass directions and true or geographic compass directions differ (referred to as magnetic ...
suggest that the magnetic compass is a well-developed component of the orientation/navigation system. Diego-Rasilla � Rosa M. Luengo � John B. Phillips Magnetic compass mediates nocturnal homing to investigate the use of magnetic compass cues in the ...
Fall migratory monarch butterflies, tested for their directional responses to magnetic cues under three conditions, amagnetic, normal, and reversed magnetic fields, showed three distinct patterns. In the absence of a magnetic field, monarchs lacked directionality as a group. In the normal magnetic field, monarchs ...
... The accuracy of the compass can thereby be tested. (Author). Descriptors : *Patents, *Compasses, *Calibration, *Sonar arrays, *Magnetic fields ...
Designed for instructors with little or no map and compass experience, the self-contained manual contains background information, lesson plans, student handouts, and references for teaching the basic skills of map and compass use to junior high and senior high school students and youth groups. An introductory section briefly discusses the importance of map ...
ERIC Educational Resources Information Center
The magnetic compass of migratory birds has been suggested to be light-dependent. Retinal cryptochrome-expressing neurons and a forebrain region, �Cluster N�, show high neuronal activity when night-migratory songbirds perform magnetic compass orientation. By combining neuronal tracing with ...
... a. Level and plumb a test item over a surveyed observation post (OP ... b. Orient the test item to grid north using the magnetic needle or compass and ...
The system is for transmitting information concerning the orientation of a hydrophone with respect to some fixed point such as magnetic north. The hydrophone is associated with a liquid-filled container housing a rotary assembly consisting of a shaft, rin...
: navigation, homing, magnetic field, newt, Notophthalmus viridescens, map detector, natural remanent magnetism., 2001) and (2) map-based homing orientation (`true navigation'), which utilizes both compass, 2002; Fischer et al., 2001). The magnetic field provides a source of ...
This Topic in Depth explores the Web's offering on compasses. The first site is another great site from How Stuff Works.com called How Compasses Work (1). Visitors can read the interesting text and view attractive graphics on the basics of what a compass is and how it is used. The second site, maintained by ...
Magnetism. How A Compass Works. -Pick up a compass and hold it in your hand. - Turn the compass holder around so that the N, for North, is under the pointed ...
NASA Website
The aim of our study was to test for lateralization of magnetic compass orientation in pigeons. Having shown that pigeons are capable of learning magnetic compass directions in an operant task, we wanted to know whether the brain hemispheres contribute differently and how the lateralization ...
Migrating Songbirds Recalibrate Their Magnetic Compass Daily from Twilight Cues William W. Cochran of magnetic, stellar, and twilight orientation cues in free-flying songbirds. We exposed Catharus thrushes calibrated daily from twilight cues. This could explain how birds cross the magnetic ...
, Passerculus sandwichensis, recalibrated their magnetic compass when exposed to con- flicting magnetic
The avian navigational system is based on an external reference, giving the home direction as a compass course. When young, inexperienced birds begin to fly, their only available orientation mechanism is a magnetic compass provided by their ability to perceive the geomagnetic field. They navigate by using this ...
... that amphibians use both celestial cues and the geomagnetic field for y-axis orientation. However, few studies have ... of the y-axis with respect to the geomagnetic field within 12�16 h. In conjunction w...
NBII National Biological Information Infrastructure
... orient along the Y-axis by sensing the geomagnetic field. C. GuyersubmittedDecember 9, 2000; Accepted: July 11, 2001 ... within 3% and 1°, respectively of the ambient geomagnetic field. During the test, a...
). Use of an inclination compass during migratory orientation by the bobolink (Dolichonyx oryzivorus of the bobolink Dolichonyx oryzivorus. Neurosci. Lett. 80, 229-234. Bullock, T. H. and Horridge, G. A. (1965
While the role of magnetic cues for compass orientation has been confirmed in numerous animals, the mechanism of detection is still debated. Two hypotheses have been proposed, one based on a light dependent mechanism, apparently used by birds and another based on a "compass organelle" containing the iron oxide ...
While the role of magnetic cues for compass orientation has been confirmed in numerous animals, the mechanism of detection is still debated. Two hypotheses have been proposed, one based on a light dependent mechanism, apparently used by birds and another based on a �compass organelle� containing the iron oxide ...
Recent experimental studies (since ca. 1985) on the ontogeny of orientation mechanisms in migratory birds are reviewed. The processes and interactions are synthesized into a framework that may help identify critical research questions. Birds that grow up in the earth's magnetic field develop the ability to perform appropriate migratory ...
In many animal species, geomagnetic compass sensitivity has been demonstrated to depend on spectral composition of light to which moving animals are exposed. Besides a loss of magnetic orientation, cases of a shift in the compass direction by 90 degrees following a change in the colour of light have also been ...
... the magnetic compass compared to ... APPLICATIONS, *GYROSCOPES, CALIBRATION, BEARING(DIRECTION), COMPASSES, ERROR ...
Here, we provide evidence for a wavelength-dependent effect of light on magnetic compass orientation in Pelophylax perezi (order Anura), similar to that observed in Rana catesbeiana (order Anura) and Notophthalmus viridescens (order Urodela), and confirm for the first time in an anuran amphibian that a 90� shift in the direction of ...
NASA Astrophysics Data System (ADS)
Apr 7, 2011 ... The end of the compass that points to geographic North was called the north magnetic pole of the compass. The magnetic compass was brought ...
Migratory birds use multiple sources of compass information for orientation, including the geomagnetic field, the sun, skylight polarization patterns and star patterns. In this paper we review the results of cue-conflict experiments designed to determine the relative importance of the different compass mechanisms, and how directional ...
The Earth's magnetic field and celestial cues provide animals with compass information during migration. Inherited magnetic compass courses are selected based on the angle of inclination, making it difficult to orient in the near vertical fields found at high geomagnetic latitudes. ...
Magnetic compass orientation by amphibians, and some insects, is mediated by a light-dependent magnetoreception mechanism. Cryptochrome photopigments, best known for their role in circadian rhythms, are proposed to mediate such responses. In this paper, we explore light-dependent properties of magnetic sensing at ...
... the earth's magnetic field, the sun's azimuth, the polarized light pattern during the day, or ... estimated by the change in the sun's azimuth over a 7-hour period when the experiments ... ...
Bats famously orientate at night by echolocation, but this works over only a short range, and little is known about how they navigate over longer distances. Here we show that the homing behaviour of Eptesicus fuscus, known as the big brown bat, can be altered by artificially shifting the Earth's magnetic field, indicating that these bats rely on a ...
... the needle of a compass. ... FORCE FACILITIES, CALIBRATION, CONSTRUCTION MATERIALS ... DEFLECTION, MAGNETIC FIELDS, COMPASSES. ...
Night migratory songbirds can use stars, sun, geomagnetic field, and polarized light for orientation when tested in captivity. We studied the interaction of magnetic, stellar, and twilight orientation cues in free-flying songbirds. We exposed Catharus thrushes to eastward-turned magnetic fields during the twilight ...
Recently, oscillating magnetic fields in the MHz-range were introduced as a useful diagnostic tool to identify the mechanism underlying magnetoreception. The effect of very weak high-frequency fields on the orientation of migratory birds indicates that the avian magnetic compass is based on a radical pair ...
Lateralization of brain functions, once believed to be a human characteristic, has now been found to be widespread among vertebrates. In birds, asymmetries of visual functions are well studied, with each hemisphere being specialized for different tasks. Here we report lateralized functions of the birds' visual system associated with magnetoperception, resulting in an extreme asymmetry of sensing ...
The avian magnetic compass is an inclination compass that appears to be based on radical pair processes. It requires light from the short-wavelength range of the spectrum up to 565 nm green light; under longer wavelengths, birds are disoriented. When pre-exposed to longer wavelengths for 1 h, however, they show ...
Kelsey and Ryan show how to use a compass as they race through their orienteering course in this video segment from ZOOM.
Students learn to use a geologic compass to measure rock fractures and formulate a hypothesis to explain the origin of the fractures
A current model suggests that magnetoreception of compass information starts with light-dependent primary processes. Light-dependency of magnetoreception is supported by behavioral experiments with homing pigeons and caged migratory birds. Three passerine species showed normal orientation under dim monochromatic light from the blue-green range of the ...
The interaction and hierarchy of celestial and magnetic compass cues used by migratory songbirds for orientation has long been the topic of an intense debate. We have previously shown that migratory Savannah sparrows, Passerculus sandwichensis, use polarized light cues near the horizon at sunrise and sunset to recalibrate their ...
AbstractThe avian magnetic compass has been well characterized in behavioral tests: it is an �inclination compass� based on the inclination of the field lines rather than on the polarity, and its operation requires short-wavelength light. The �radical pair� model suggests that these properties reflect the use of specialized ...
Animals use the geomagnetic field in many ways: the magnetic vector provides a compass; magnetic intensity and/or inclination play a role as a component of the navigational 'map', and magnetic conditions of certain regions act as 'sign posts' or triggers, eliciting specific responses. A ...
The use of multiple compasses to map and visualize magnetic fields is well-known. The magnetic field exerts a torque on the compasses aligning them along the lines of force. Some science museums show the field of a magnet using a table with many compasses in a closely ...
Recent evidence suggests that bats can detect the geomagnetic field, but the way in which this is used by them for navigation to a home roost remains unresolved. The geomagnetic field may be used by animals both to indicate direction and to locate position. In birds, directional information appears to be derived from an interaction of the magnetic field with either the sun or ...
One of the two principal hypotheses put forward to explain the primary magnetoreception event underlying the magnetic compass sense of migratory birds is based on a magnetically sensitive chemical reaction. It has been proposed that a spin-correlated radical pair is produced photochemically in a cryptochrome and that the rates and ...
This paper presents the thoughts and experiences of marine navigators of the mid-20th century in their use of compasses during the transition from magnetic to gyro compasses.
Behavior and electrophysiological studies have demonstrated a sensitivity to characteristics of the Geomagnetic field that can be used for navigation, both for direction finding (compass) and position finding (map). The avian magnetic compass receptor appears to be a light-dependent, wavelength-sensitive system that functions as a ...
Magnetic compasses, sun compasses, sextants, and dead reckoning are all valuable tools to the Antarctic traveler, but they each have their drawbacks. ...
To verify the existence of a magnetic compass in birds, researchers have often released homing pigeons under overcast skies that are equipped with bar magnets on various parts of their body. In particular, Keeton was successful in finding disorientation in overcast conditions in a first series of tests, but not in a second series. The ...
Students use compasses and a map of campus to navigate and find orienteering markers. This lab helps to reinforce map navigation skills. Students enjoyed the activity.
Ever wonder how a compass worked to point you to the Arctic? Explore the interactions between a compass and bar magnet, and then add the earth and find the surprising answer! Vary the magnet's strength, and see how things change both inside and outside. Use the field meter to measure how the ...
The currently discussed model of magnetoreception in birds proposes that the direction of the magnetic field is perceived by radical-pair processes in specialized photoreceptors, with cryptochromes suggested as potential candidate molecules mediating magnetic compass information. Behavioral studies have shown that ...
Behavioural experiments for magnetoreception in eusocial insects in the last decade are reviewed. Ants and bees use the geomagnetic field to orient and navigate in areas around their nests and along migratory paths. Bees show sensitivity to small changes in magnetic fields in conditioning experiments and when exiting the hive. For the first time, the ...
Migratory birds are able to use the sun and associated polarised light patterns, stellar cues and the geomagnetic field for orientation. No general agreement has been reached regarding the hierarchy of orientation cues. Recent data from naturally migrating North American Catharus thrushes suggests that they calibrate geomagnetic information daily from ...
The radical pair model of magnetoreception predicts that magnetic compass orientation can be disrupted by high frequency magnetic fields in the Megahertz range. European robins, Erithacus rubecula, were tested under monochromatic 565 nm green light in 1.315 MHz fields of 0.48 ?T during spring and autumn migration, ...
(Plectrophenax nivalis) have access to a magnetic compass and that they use it as a primary tool for orientation buntings (Plectrophenax nivalis) during their autumn migration in a natural near-vertical geomagnetic field nivalis, snow bunting. Summary Introduction ORIENTATION OF SNOW BUNTINGS (PLECTROPHENAX ...
- spectrum light excluded; see Fig. 5). The experiments showed that both juvenile and adult birds under 565nm or full-spectrum light (Wiltschko 3845The Journal of Experimental Biology 205, 3845) to produce full- spectrum and monochromatic light (see Fig. 1). From ultraviolet (UV;
Leaf-cutter ants Atta colombica forage over 250 m in structurally-complex, Neotropical rainforests that occlude sun or polarized light cues. Night foraging makes the use of celestial cues and landmarks all the more difficult. We investigated the directional cues used by leaf-cutter ants to orient h...
This paper reviews the directional orientation of birds with the help of the geomagnetic field under various light conditions. Two fundamentally different types of response can be distinguished. (i) Compass orientation controlled by the inclination compass that allows birds to locate courses of different origin. ...
Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds ...
--882. Mouritsen, H. & Frost, B. J. 2002: Virtual migration in tethered flying monarch butterflies reveals biological compass, having been demonstrated in many animal classes ranging from insects [e.g. monarch butterflies (Danaus plexippus); Mouritsen & Frost 2002] to birds (Schmidt-Koenig 1958). Where magnetic
Sharks, skates, and rays receive electrical information about the positions of their prey, the drift of ocean currents, and their magnetic compass headings. At sea, dogfish and blue sharks were observed to execute apparent feeding responses to dipole electric fields designed to mimic prey. In training experiments, stingrays showed the ability to ...
PRODUCE MAGNETITE? "Act as a compass to help bacteria orient and navigate .... " Populations of inorganic magnetite display at most 2 or ...
The earth acts like a very large magnet. That is why a compass always points North. Just as any two magnets will pull on each other, the compass needle and ...
Using oar magnets, ciassroom materials, and a compass, students will explore ... 1 compass per student; 2 nlnico oar magnets; -I sheets oi SW x 11" paper; ...
This article reports the result of an experiment that was designed to measure the biomagnetic field emanating from two individuals who were practising traditional Oriental Qi Gong breathing exercises. The biomagnetic field was measured with differential coils wound 80,000 turns, a magnetic needle compass and a digital electromagnetic ...
The EJS Magnetic Multipole Field Model shows the field of a magnetic dipole or quadrupole with little compasses that indicate direction and relative field strength. A slider changes the angular orientation of the dipole and a movable compass shows the magnetic field ...
This demonstration of the magnetic field lines of Earth uses a bar magnet, iron filings, and a compass. The site explains how to measure the magnetic field of the Earth by measuring the direction a compass points from various points on the surface. There is also an explanation of why the north ...
The use of the magnetic compass in China is documented at least since the Han dynasty (206 BC-220 AD), but may be older. Geomancy (fengshui) practicised for a long time had a profound influence on the face of China's landscape and city plans. The tombs (pyramids) near Xian (together with suburban fields and roads) have strange space ...
Orientation tests were conducted with snow buntings (Plectrophenax nivalis) exposed to artificially manipulated magnetic fields, during both spring and autumn migration. Experiments were run under clear sunset skies and under simulated complete overcast. The birds closely followed experimental shifts of the magnetic fields during both ...
A remotely readable fiber optic compass. A sheet polarizer is affixed to a magnet rotatably mounted in a compass body, such that the polarizer rotates with the magnet. The optical axis of the sheet polarizer is preferably aligned with the north-south axis...
Identifying the mechanism in birds that controls magnetic orientation behavior is proving elusive and is currently attracting a plethora of research activity. Much of this research involves wild birds that are caught in nets, tested and released. Ethical concerns regarding these experiments are likely to encompass the welfare of animals, their "rights" and ...
Identifying the mechanism in birds that controls magnetic orientation behavior is proving elusive and is currently attracting a plethora of research activity. Much of this research involves wild birds that are caught in nets, tested and released. Ethical concerns regarding these experiments are likely to encompass the welfare of animals, their �rights� ...
It is not yet understood how migratory birds sense the Earth's magnetic field as a source of compass information. One suggestion is that the magnetoreceptor involves a photochemical reaction whose product yields are sensitive to external magnetic fields. Specifically, a flavin-tryptophan radical pair is supposedly formed by ...
Language: English ...
...2010-10-01 false Magnetic Compass and Gyrocompass-T...AND HULL REQUIREMENTS Navigation Equipment § 32.15-35 Magnetic Compass and Gyrocompass...service must be fitted with a magnetic compass. (b)...
Code of Federal Regulations, 2010
compass during migratory orientation by the bobolink (Dolichonyx oryzivorus). Ethology 81, 291-299. Beason by the bobolink (Dolichonyx oryzivorus). Ethology 91, 75-80. Beason R. C., and Semm, P. (1987). Magnetic responses of the trigeminal nerve system of the bobolink (Dolichonyx oryzivorus). Neurosci. Lett. 80, 229-234. Brodie E. D
Leaf-cutter ants Atta colombica forage over 250 m in structurally-complex, Neotropical rainforests that occlude sun or polarized light cues. Night foraging makes the use of celestial cues and landmarks all the more difficult. Typically leaf-cutter ants follow architecturally-modified, pheromonally-m...
Explore the interactions between a compass and bar magnet. Discover how you can use a battery and wire to make a magnet! Can you make it a stronger magnet? Can you make the magnetic field reverse?
This activity helps students understand why compass angles need to be corrected for regional magnetic variation. The magnetic compass, perfected slowly over years of experimentation, trial, and scientific endeavor, became the sailor's most common and most reliable direction-indicating aid, but is influenced by ...
Passerine migrants require light from the blue-green part of the spectrum for magnetic compass orientation; under yellow light, they are disoriented. European robins tested under a combination of yellow light and blue or green light showed a change in behavior, no longer preferring their seasonally appropriate migratory direction: in ...
Where on Earth are you? Where is your home, your school, or the bookstore on the globe we call Earth? The activities in this book are designed to show children how to orient themselves on this planet. The book is divided into three main sections. Section 1, "Finding North, No Matter What," contains the following subsections: (1) Finding North with a Watch; (2) Finding North by ...
... All survey typo cruises conducted by this project to date have been ... Magnetic Compass Pilot Set Power Steering Set Gyro Compass Deep Freeze I � ...
... system compass installation in the Vulcan B. Mk. 2 provides a satisfactory gyro-magnetic compass system for navigational use. The Track Control ...
Magnetic orientation has been demonstrated in Siberian hamsters, Phodopus sungorus. The behavior, using a nest building assay, shows a directional preference in nest position and appears in this animal to be a learned behavior. Hamsters were housed prior to testing in rectangular cages aligned along perpendicular axes. When subsequently tested in a ...
Energy Citations Database
Magnetic compass orientation in birds has been shown to be light dependent. Results from behavioural studies indicate that magnetoreception capabilities are disrupted under light of peak wavelengths longer than 565 nm, and shifts in orientation have been observed at higher light intensities (43-44x10(15) quanta ...
Magnetic compasses are widely used in vehicle navigation systems to measure the vehicle headings with respect to the Earth's magnetic north. Due to the local variation of the Earth's magnetic flux density and the induced magnetic field of the magnetized vehicle body, ...
(MEMS) are used to realize the various flight control sensing devices. MEMS- based ... Magnetic sensor. " Magnetic compass. " Temperature sensor ...
Nov 25, 2001 ... The nature of magnetism and the strange directional properties of the compass were a complete mystery. For instance, no garlic was allowed ...
Migration routes of birds throw light on orientation performance at different geographic scales, over distances ranging from a few kilometres to more than 104 km. Detailed knowledge about the flight routes may be used to test predictions about optimal orientation according to theoretical principles and about the use of compasses based ...
Cryptochromes (Cry) have been suggested to form the basis of light-dependent magnetic compass orientation in birds. However, to function as magnetic compass sensors, the cryptochromes of migratory birds must possess a number of key biophysical characteristics. Most importantly, absorption of ...
This paper describes the use of a fluxgate compass to provide accurate heading information for autonomous underwater vehicles. Two sources of error are identified: steady state bias and compass lag. Results of field tests comparing a fluxgate and a refere...
...VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 184.402 Compasses. (a) Except...in this section every vessel must be fitted with a suitable magnetic compass designed for marine use, to be mounted at the...
... VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.402 Compasses. (a) Except as...in this section every vessel must be fitted with a suitable magnetic compass designed for marine use, to be mounted at the...
In this OLogy activity, kids learn how a compass works and why it will always point north. The activity begins with an overview that discusses our reliance on directions and how a compass works. Students are then given step-by-step, illustrated directions for creating a compass with a sewing needle, a small bar ...
This study examined neural activation during the experience of compassion, an emotion that orients people toward vulnerable others and prompts caregiving, and pride, a self-focused emotion that signals individual strength and heightened status. Functional magnetic resonance images (fMRI) were acquired as participants viewed 55?s ...
Determining how animals perform long-distance animal migration remains one of the most enduring and fundamental mysteries of behavioural ecology. It is widely accepted that navigation relative to a reference datum is a fundamental requirement of long-distance return migration between seasonal habitats, and significant experimental research has documented a variety of viable ...
Considering the unique morphology (purposefully shaped polished bar with a groove) and composition (magnetic mineral with magnetic moment vector in the floating plane) of M-160, and acknowledging that the Olmec were a sophisticated people who possessed advanced knowledge and skill in working iron ore minerals, I would suggest for consideration that the ...
The blind mole rat Spalax ehrenbergi is a solitary, subterranean rodent that digs and inhabits a system of branching tunnels, with no above-ground exits, which it never leaves unless forced to. To survive, the mole rat must be able to orient efficiently in its tunnel system. The sensory channels available for spatial orientation in the subterranean ...
The animations represent two typical bar magnets each with a North and South pole. The user may drage either magnet, add magnetic field lines, or add a compass.
The purpose of this note is to give the method for calculating the perturbation introduced into a uniform magnetic field by the presence of an unmagnetized magnetic ellipsoid. The immediate application is the determination of the error introduced into the...
Previous experiments have shown that a short, strong magnetic pulse caused migratory birds to change their headings from their normal migratory direction to an easterly direction in both spring and autumn. In order to analyse the nature of this pulse effect, we subjected migratory Australian silvereyes, Zosterops lateralis, to a magnetic pulse and tested ...
The Radical Pair Mechanism(RPM) has been proposed to explain the avian magnetic orientation process. The dependence of radical pair reactions on the direction of external magnetic held makes radical-pair reactions potential magnetic sensors. Previous studies have explained why a weak magnetic ...
Investigations conducted to determine the nature and cause of magnetic field disturbances at the calibration hardstand (compass rose) at LRAFB included the characterization of the total magnetic field strength horizontally and vertically both on and off t...
Under 502 nm turquoise light combined with 590 nm yellow light and in total darkness, European robins, Erithacus rubecula, no longer prefer their migratory direction, but exhibit so-called fixed direction responses that do not show the seasonal change between spring and autumn. We tested robins under these light conditions in the local geomagnetic field of 46 ?T, a field of twice this intensity, ...
Under 502 nm turquoise light combined with 590 nm yellow light and in total darkness, European robins, Erithacus rubecula, no longer prefer their migratory direction, but exhibit so-called fixed direction responses that do not show the seasonal change between spring and autumn. We tested robins under these light conditions in the local geomagnetic field of 46 microT, a field of twice this ...
For centuries, navigators of the world's oceans have been familiar with an effect of Earth's magnetic field: It imparts a directional preference to the needle of a compass. Although in some settings magnetic orientation remains important, the modern science of geomagnetism has emerged from its romantic nautical ...
USGS Publications Warehouse
Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass guided ...
A newly developed flight simulator allows monarch butterflies to fly actively for up to several hours in any horizontal direction while their fall migratory flight direction can be continuously recorded. From these data, long segments of virtual flight paths of tethered, flying, migratory monarch butterflies were reconstructed, and by advancing or retarding the butterflies' circadian clocks, we ...
Migratory birds use celestial and geomagnetic directional information to orient on their way between breeding and wintering areas. Cue-conflict experiments involving these two orientation cue systems have shown that directional information can be transferred from one system to the other by calibration. We designed experiments with four species of North ...
In the introductory chapter the physical and interfacial properties of cadmium selenide are presented, as well as a discussion of select surface properties of CdSe. Also, a brief review of scanning probe lithographic techniques currently under investigation is presented. As a portion of the project presented herein, a research-grade scanning tunneling microscope was constructed. The second chapter ...
Two conflicting hypotheses compete to explain how a homing pigeon can return to its loft over great distances. One proposes the use of atmospheric odours and the other the Earth's magnetic field in the 'map' step of the 'map and compass' hypothesis of pigeon homing. Although magnetic effects on pigeon orientation ...
Two conflicting hypotheses compete to explain how a homing pigeon can return to its loft over great distances. One proposes the use of atmospheric odours and the other the Earth's magnetic field in the `map' step of the `map and compass' hypothesis of pigeon homing. Although magnetic effects on pigeon orientation ...
Compasses are useful tools for teaching the basics of navigation. Knowing where you are, where you are going, and how to get there are important facets of outdoor recreation. Compass games are a fun way to teach introductory navigation skills, and this article describes how they can be used as innovative, nontraditional activities in physical education. ...
, D.L., 1961. The Orientation of Animals: Kineses, Taxes and Compass Orientation. Dover Publications
Arctic waders are well known for their impressive long-distance migrations between their high northerly breeding grounds and wintering areas in the Southern hemisphere. Performing such long migrations requires precise orientation mechanisms. We conducted orientation cage experiments with juvenile sharp-tailed sandpipers (Calidris acuminata) to investigate ...
Sep 24, 1996 ... And, just as the magnetic field of a bar magnet pushes iron filings into a pattern, so too does the Earth's magnetic field. That is why a compass ...
The Earth is also a giant magnet. You can use it to find your direction by using a compass. Scientists have studied Earth's magnetic field for hundreds of years. ...
This is a group of frequently asked questions and answers about Earth's magnetic field and poles, the magnetic compass, magnetic reversals, and geomagnetic models. Links to maps and illustrations are embedded in the text.
The animations represent a typical bar magnet with a North and South pole. The user may double click anywhere inside the animation to add a magnetic field line and also add a compass.
Biologists think that bacteria use these as built-in magnetic compasses ... So, only bacteria seem to have both an organ and a need for magnetic navigation. ...
Although ferrimagnetic material appears suitable as a basis of magnetic field perception in animals, it is not known by which mechanism magnetic particles may transduce the magnetic field into a nerve signal. Provided that magnetic particles have remanence or anisotropic magnetic ...
The migratory orientation of sanderlings (Calidris alba) was investigated with cage experiments during the spring migration in southwest Iceland. Sanderlings were exposed to 90 degrees counterclockwise-shifted magnetic fields under both clear skies and natural overcast. Clear sky control tests resulted in a northerly mean direction, in agreement with ...
Apr 16, 2007 ... Captain John Smith listed the astrolabe and magnetic compass as ... Mariners, or sailors, used an astrolabe to find the angle of the sun or ...
joined semicircular pieces of bismuth and copper (Figure 1) while studying thermal effects on galvanic arrangements. A nearby compass indicated a magnetic disturbance.
... design. ... and evaluation of this receiver clearly demonstrates that off the shelf ... preferred magnetic compass is manufactured by KVH Industries and is ...
... phase signal was subsequently applied to the appropriate compass calibration curve to obtain the magnetic heading of ...
... using an electronic compass indoors for heading reference [13]. Instead, assuming ... �fingerprint� for an indoor environment. ...
Contents: A Positive Seal Water Bottle; Magnetically Actuated Event Counter; and Aanderaa Compass Calibrations.
This U.S. Geological Survey fact sheet introduces topographic maps and explains how scale is used in a map to convey distance, how direction is determined using a compass, and how to use both a map and compass together by taking a compass bearing from a map. Contacts are provided to obtain current and historical ...
...2010-10-01 false Magnetic compass and gyrocompass. 167.40-45 Section 167.40-45 Shipping COAST GUARD, DEPARTMENT...SCHOOL SHIPS Certain Equipment Requirements § 167.40-45 Magnetic compass and...
During their fall migration, Eastern North American monarch butterflies (Danaus plexippus) use a time-compensated Sun compass to aid navigation to their overwintering grounds in central Mexico. It has been assumed that the circadian clock that provides time compensation resides in the brain, although this assumption has never been examined directly. Here, we show that the ...
During their fall migration, Eastern North American monarch butterflies (Danaus plexippus) use a time-compensated sun compass to aid navigation to their overwintering grounds in central Mexico. It has been assumed that the circadian clock that provides time compensation resides in the brain, although this assumption has never been examined directly. Here we show that the ...
BackgroundEuropean robins, Erithacus rubecula, show two types of directional responses to the magnetic field: (1) compass orientation that is based on radical pair processes and lateralized in favor of the right eye and (2) so-called 'fixed direction' responses that originate in the magnetite-based receptors in the upper beak. Both ...
Magnetotactic bacteria (mtb) migrate along geomagnetic field lines, i.e., they behave like self-propelled magnetic compass needles. Mtb make single-magnetic-domain crystals of magnetite (Fe3O4) and greigite (Fe3S4) in intracellular structures called magnetosomes. The magnetosomes are arranged in linear chains that comprise permanent ...
Discusses the properties of neodymium magnets and magnets in general and how magnets can be used to teach students important scientific principles, such as attraction, repulsion, and polarity; the role of magnetic forces in electronic communications and computers; the magnetic properties of the ...
Loggerhead sea turtle hatchlings (Caretta caretta L.) emerge from underground nests, scramble to the sea and begin a transoceanic migration by swimming away from their natal beach and into the open ocean. Evidence suggests that hatchlings sequentially use three different sets of cues to maintain orientation during their initial migration offshore. While on the beach, ...
What is compassion? And how did it evolve? In this review, we integrate 3 evolutionary arguments that converge on the hypothesis that compassion evolved as a distinct affective experience whose primary function is to facilitate cooperation and protection of the weak and those who suffer. Our empirical review reveals compassion to have ...
What is compassion? And how did it evolve? In this review, we integrate three evolutionary arguments that converge on the hypothesis that compassion evolved as a distinct affective experience whose primary function is to facilitate cooperation and protection of the weak and those who suffer. Our empirical review reveals compassion to ...
THAT the pre-Columbian peoples of Mesoamerica were familiar with the property of magnetism has been suggested by numerous researchers, among them Coe and Fuson1. Indeed, a flattened oblong piece of haematite discovered by Coe during the excavation of the Olmec site of San Lorenzo in southern Veracruz state in 1973, has been thoroughly examined by Carlson2, who suggests that it ...
A quantitative frequency-domain model of induction-based magnetoreception is presented for elasmobranch fishes. We show that orientation with respect to the geomagnetic field can be determined by synchronous detection of electrosensory signals at harmonics of the vestibular frequency. The sensitivity required for this compass-sense mechanism is shown to be ...
