Magnetoreception systems in birds: A review of current research

Kishkinev, Dmitry; Chernetsov, Nikita

doi:10.1134/s2079086415010041

Cited by 33 publications

(26 citation statements)

References 144 publications

(171 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Annealing the system above 663 K leads to the diffusion of Co into the bulk oxide, with no trace remaining in XPS (see Figure 92). Consistent with this, DFT+U calculations find that Co oct 2+ cations are preferably incorporated in bulk-like (S-6) layers of a Fe 3 O 4 slab than in the surface (S) or subsurface layers (S-2) (see Table 7) 4 films with x between 0 and 1.56 and found the spinel structure maintained up to 0.56, above which there was significant degree of inversion defects (i.e. cobalt on octahedral sites and iron on tetrahedral sites).…”

Section: Cobaltsupporting

confidence: 50%

Iron oxide surfaces

Parkinson

2016

Surface Science Reports

501

463

View full text Add to dashboard Cite

The current status of knowledge regarding the surfaces of the iron oxides, magnetite (Fe 3 O 4 ), maghemite (γ-Fe 2 O 3 ), hematite (α-Fe 2 O 3 ), and wüstite (Fe 1-x O) is reviewed. The paper starts with a summary of applications where iron oxide surfaces play a major role, including corrosion, catalysis, spintronics, magnetic nanoparticles (MNPs), biomedicine, photoelectrochemical water splitting and groundwater remediation. The bulk structure and properties are then briefly presented; each compound is based on a close-packed anion lattice, with a different distribution and oxidation state of the Fe cations in interstitial sites. The bulk defect chemistry is dominated by cation vacancies and interstitials (not oxygen vacancies) and this provides the context to understand iron oxide surfaces, which represent the front line in reduction and oxidation processes. The atomic-scale structure of the low-index surfaces of iron oxides is the major focus of this review. Fe 3 O 4 is the most studied iron oxide in surface science, primarily because its stability range corresponds nicely to the ultra-high vacuum environment, and because it is an electrical conductor, which makes it straightforward to study with the most commonly used surface science methods such as photoemission spectroscopies (XPS, UPS) and scanning tunneling microscopy (STM). The impact of the surfaces on the measurement of bulk properties such as magnetism, the Verwey transition and the (predicted) half-metallicity is discussed.The best understood iron oxide surface at present is probably Fe 3 O 4 (100); the structure is known with a high degree of precision and the major defects and properties are well characterised. A major factor in this is that a termination at the Fe oct -O plane can be reproducibly prepared by a variety of methods, as long as the surface is annealed in 10 Such straightforward preparation of a monophase termination is generally not the case for other iron oxide surfaces. All available evidence suggests the oft-studied (√2×√2)R45° reconstruction results from a rearrangement of the cation lattice in the outermost unit cell in which two octahedral cations are replaced by one tetrahedral interstitial, a motif conceptually similar to well-known Koch-Cohen defects in Fe (0001) is the most studied hematite surface, but 2 difficulties preparing stoichiometric surfaces under UHV conditions have hampered a definitive determination of the structure. There is evidence for at least three terminations: a bulk-like termination at the oxygen plane, a termination with half of the cation layer, and a termination with ferryl groups. When the surface is reduced the so-called "bi-phase" structure is formed, which eventually transforms to a Fe 3 O 4 (111)-like termination. The structure of the bi-phase surface is controversial; a largely accepted model of coexisting Fe 1-x O and α-Fe 2 O 3 (0001) islands was recently challenged and a new structure based on a thin film of Fe 3 O 4 (111) on α-Fe 2 O 3 (0001) was proposed. The merits of the compet...

show abstract

Section: Cobaltsupporting

confidence: 50%

Iron oxide surfaces

Parkinson

2016

Surface Science Reports

501

463

View full text Add to dashboard Cite

show abstract

“…Interestingly, when a direct view of the prey was obstructed by high vegetation or snow cover, foxes more accurately aligned their attacks to the north-northeast and were approximately 3-4 times more successful at capturing prey than when aligned in other magnetic directions [27]. The authors proposed that the alignment behavior observed in foxes could be mediated by a light-dependent magnetoreception mechanism, similar to that used by migratory birds, newts, and insects [7,14,[28][29][30][31][32][33] where specialized photopigments undergo a photo-induced chemical reaction that is sensitive to the alignment of the magnetic field. In animals where these photopigments are located in the retina, the magnetic field may be perceived as a three-dimensional pattern of light intensity or color superimposed on the animal's visual surrounding and fixed in alignment with respect to magnetic north [26,34].…”

Section: Introductionmentioning

confidence: 93%

“…In particular, 'magnetic bio-loggers' used in studies of animal navigation and orientation could provide important new evidence for behavioral responses dependent on the geomagnetic field [7][8][9][10][11][12][13][14]. For example, several studies have reported evidence of spontaneous magnetic alignment (SMA) behavior across a range of vertebrates that show a strong tendency to align the anteroposterior axis bimodally along the north-south magnetic axis [for reviews see 15, 16, and recently 17].…”

Section: Introductionmentioning

confidence: 99%

Use of bio-loggers to characterize red fox behavior with implications for studies of magnetic alignment responses in free-roaming animals

et al. 2016

View full text Add to dashboard Cite

Background: Spontaneous magnetic alignment (SMA), in which animals position their body axis in fixed alignments relative to magnetic field lines, has been shown in several classes of vertebrates and invertebrates. Although these responses appear to be widespread, the functional significance and sensory mechanism(s) underlying SMA remain unclear. An intriguing example comes from observations of wild red foxes (Vulpes vulpes) that show a ~fourfold increase in hunting success when predatory 'mousing' attacks are directed toward magnetic north-northeast. This form of SMA is proposed to receive input from a photoreceptor-based magnetoreception mechanism perceived as a 'visual pattern' and used as a targeting system to increase the accuracy of mousing attempts targeting hidden prey. However, similar to previous observational studies of magnetic orientation in vertebrates, direct evidence for the use of magnetic cues, and field-based experiments designed to characterize the biophysical mechanisms of SMA are lacking. Here, we develop a new approach for studies of SMA using triaxial accelerometer and magnetometer bio-loggers attached to semidomesticated red foxes.Results: Accelerometer data were recorded from 415 ground-truth events of three behaviors exhibited by an adult red fox. A 5-nearest neighbor classifier was developed for behavioral analysis and performed with an accuracy of 95.7% across all three behaviors. To evaluate the generalizability of the classifier, data from a second fox were tested yielding an accuracy of 66.7%, suggesting the classifier can extract behaviors across multiple foxes. A similar classification approach was used to identify the fox's magnetic alignment using two 8-way classifiers with differing underlying assumptions to distinguish magnetic headings in eight equally spaced 45° sectors. The magnetic heading classifiers performed with 90.0 and 74.2% accuracy, suggesting a realistic performance range for a classifier based on an independent set of training events equal in size to our sample. Conclusions:We report the development of 'magnetic ethograms' in which the behavior and magnetic alignment of foxes can be accurately extracted from raw sensor data. These techniques provide the basis for future studies of SMA where direct observation is not necessary and may allow for more sophisticated experimental designs aimed to characterize the sensory mechanisms mediating SMA behavior.

show abstract

“…Then the animal chooses and maintains the direction towards the goal with the help of ''a compass'' mechanism using natural directional references (e.g., solar, stellar, and geomagnetic cues). Studies conducted from the 1950s through the late 1990s revealed the behavioural principles underlying different avian compass mechanisms (Emlen 1967a(Emlen , b, 1975Kramer 1950a, b;Schmidt-Koenig et al 1991;Wiltschko and Wiltschko 1972;Wiltschko et al 1993), but physical, molecular, anatomical and neurophysiological aspects of avian compasses, especially the magnetic one, still remain to be solved and lie beyond the scope of this review (see Kishkinev and Chernetsov 2015; Mouritsen and Hore 2012 for review). The natural cues used by birds for positioning, the principles of the map used, and the sensory systems involved in positioning represent the least understood part in this field.…”

Section: Possible Concepts For a Map Used For True Navigationmentioning

confidence: 96%

“…Recently, Anna Gagliardo and co-workers compared the hypotheses of the olfactory and magnetic map against each other in pigeons, inspired by a growing body of evidence that the trigeminal nerve can innervate magnetoreceptors involved in magnetic navigation in some avian species (see Mouritsen and Hore 2012;Kishkinev and Chernetsov 2015, and discussion below). These studies clearly showed that pigeons with a bilaterally sectioned olfactory nerve homed worse than both sham treated and trigeminal nerve sectioned birds released from distances of 55-105 km around Pisa in Italy (Gagliardo et al 2006(Gagliardo et al , 2008).…”

Section: Olfactory Navigationmentioning

confidence: 98%

Sensory mechanisms of long-distance navigation in birds: a recent advance in the context of previous studies

Kishkinev

2015

J Ornithol

View full text Add to dashboard Cite

Displacement studies have clearly shown that experienced avian migrants are able to perform true navigation, i.e., they can find the correct direction leading to a target destination from unfamiliar sites. The sensory mechanisms of true navigation remain poorly understood, though some remarkable progress has been made in the last 10-15 years. There are two primary hypotheses explaining the sensory nature of navigation: (1) a magnetic map hypothesis proposes that birds use parameters of the geomagnetic field that are predictably distributed on the globe. As for the sensory nature of this hypothesis, it has been assumed by some researchers that the magnetic receptor cells reside in the upper beak (the so-called ''beak organ''), and transmit information via the trigeminal nerve to the brain; (2) an olfactory map hypothesis assumes that birds can smell their position by taking advantage of odours distributed in the atmosphere. There are a growing number of studies supporting both of the hypotheses mentioned though in different avian model species. In this review, an attempt is made to provide an overview of the evidence for different navigational cues proposed thus far, with the main focus on the recent studies addressing the magnetic and olfactory navigation hypotheses. Also, a list of key open questions, together with possible experimental approaches, is proposed.

show abstract

Magnetoreception systems in birds: A review of current research

Cited by 33 publications

References 144 publications

Iron oxide surfaces

Iron oxide surfaces

Use of bio-loggers to characterize red fox behavior with implications for studies of magnetic alignment responses in free-roaming animals

Sensory mechanisms of long-distance navigation in birds: a recent advance in the context of previous studies

Contact Info

Product

Resources

About