Transfer of directional information between the polarization compass and the sun compass in desert ants

2014 ◽  
Vol 201 (6) ◽  
pp. 599-608 ◽  
Author(s):  
Fleur Lebhardt ◽  
Bernhard Ronacher
Keyword(s):  
The Sun ◽  
Sun Compass ◽  
Directional Information ◽  
Desert Ants ◽  
Polarization Compass

scholarly journals Matched-filter coding of sky polarization results in an internal sun compass in the brain of the desert locust

2020 ◽  
Vol 117 (41) ◽  
pp. 25810-25817
Author(s):  
Frederick Zittrell ◽  
Keram Pfeiffer ◽  
Uwe Homberg
Keyword(s):  
Spatial Orientation ◽  
Matched Filter ◽  
Polarized Light ◽  
Central Complex ◽  
Insect Brain ◽  
The Sun ◽  
Polarization Pattern ◽  
Sun Compass ◽  
Small Spot ◽  
Polarization Compass

Many animals use celestial cues for spatial orientation. These include the sun and, in insects, the polarization pattern of the sky, which depends on the position of the sun. The central complex in the insect brain plays a key role in spatial orientation. In desert locusts, the angle of polarized light in the zenith above the animal and the direction of a simulated sun are represented in a compass-like fashion in the central complex, but how both compasses fit together for a unified representation of external space remained unclear. To address this question, we analyzed the sensitivity of intracellularly recorded central-complex neurons to the angle of polarized light presented from up to 33 positions in the animal’s dorsal visual field and injected Neurobiotin tracer for cell identification. Neurons were polarization sensitive in large parts of the virtual sky that in some cells extended to the horizon in all directions. Neurons, moreover, were tuned to spatial patterns of polarization angles that matched the sky polarization pattern of particular sun positions. The horizontal components of these calculated solar positions were topographically encoded in the protocerebral bridge of the central complex covering 360° of space. This whole-sky polarization compass does not support the earlier reported polarization compass based on stimulation from a small spot above the animal but coincides well with the previously demonstrated direct sun compass based on unpolarized light stimulation. Therefore, direct sunlight and whole-sky polarization complement each other for robust head direction coding in the locust central complex.

Hippocampal lesion effects on learning strategies in homing pigeons

1996 ◽  
Vol 263 (1370) ◽  
pp. 529-534 ◽  
Keyword(s):  
Learning Strategies ◽  
Hippocampal Lesion ◽  
Food Reward ◽  
The Sun ◽  
Sun Compass ◽  
Homing Pigeons ◽  
Directional Information ◽  
Intact Control ◽  
Hippocampal Lesions ◽  
Clock Shift

Several studies have shown that birds have a directional view of space and tend to use the sun compass over landmark beacons when both are available. Intact homing pigeons can use either the sun compass or colour beacons to locate a food reward, whereas pigeons with hippocampal lesions are unable to use the sun compass, but quickly learn to use colour beacons. We trained hippocampal ablated and intact pigeons to find a reward in an outdoor octagonal arena when both sun compass information (directional cues) and intramaze landmark beacons (colour cues) were available. The intact control pigeons learned the task by preferentially relying on directional cues while effectively ignoring the colour beacons. The behaviour of the hippocampal ablated birds, based on a clock-shift manipulation and after the rotation of the colour beacons, showed that they learned to locate the food reward in the arena only on the basis of the landmark beacons, ignoring the sun compass directional information.

The Safe Aircraft Competition, The Sun Compass, and more

1930 ◽  
Vol 142 (3) ◽  
pp. 232-234
Author(s):  
Alexander Klemin
Keyword(s):  
The Sun ◽  
Sun Compass

scholarly journals How dim is dim? Precision of the celestial compass in moonlight and sunlight

2011 ◽  
Vol 366 (1565) ◽  
pp. 697-702 ◽  
Author(s):  
M. Dacke ◽  
M. J. Byrne ◽  
E. Baird ◽  
C. H. Scholtz ◽  
E. J. Warrant
Keyword(s):  
Dung Beetle ◽  
The Sun ◽  
The Moon ◽  
Polarization Pattern ◽  
Animal Group ◽  
Straight Line ◽  
Celestial Orientation ◽  
Polarization Compass ◽  
Celestial Compass ◽  
Diurnal Species

Prominent in the sky, but not visible to humans, is a pattern of polarized skylight formed around both the Sun and the Moon. Dung beetles are, at present, the only animal group known to use the much dimmer polarization pattern formed around the Moon as a compass cue for maintaining travel direction. However, the Moon is not visible every night and the intensity of the celestial polarization pattern gradually declines as the Moon wanes. Therefore, for nocturnal orientation on all moonlit nights, the absolute sensitivity of the dung beetle's polarization detector may limit the precision of this behaviour. To test this, we studied the straight-line foraging behaviour of the nocturnal ball-rolling dung beetle Scarabaeus satyrus to establish when the Moon is too dim—and the polarization pattern too weak—to provide a reliable cue for orientation. Our results show that celestial orientation is as accurate during crescent Moon as it is during full Moon. Moreover, this orientation accuracy is equal to that measured for diurnal species that orient under the 100 million times brighter polarization pattern formed around the Sun. This indicates that, in nocturnal species, the sensitivity of the optical polarization compass can be greatly increased without any loss of precision.

Orientation and dispersal of hatchling Blanding’s turtles (Emydoidea blandingii) from experimental nests

2009 ◽  
Vol 87 (9) ◽  
pp. 755-766 ◽  
Author(s):  
M. J. Pappas ◽  
J. D. Congdon ◽  
B. J. Brecke ◽  
J. D. Capps
Keyword(s):  
Forest Succession ◽  
Environmental Cues ◽  
The Sun ◽  
Dispersal Patterns ◽  
Sun Compass ◽  
Emydoidea Blandingii ◽  
Late Afternoon ◽  
Nest Sites ◽  
Pine Trees ◽  
Riparian Habitats

We determined initial dispersal directions of 1052 naïve and 278 experienced hatchling Blanding’s turtles (Emydoidea blandingii (Holbrook, 1838)) in experimental arenas in a variety of settings. Dispersal of naïve hatchlings was nonrandom in 7 of 10 sites. All nonrandom dispersal patterns suggested hatchlings primarily used vision to orient toward dark far horizons, particularly those associated with riparian habitats. We found no evidence that hatchlings use positive geotaxis, olfaction, humidity gradients, or scent trailing of other individuals during dispersal. Despite the lack of relationships between the changing position of the sun and relationships between nest sites and wetlands, patterns of dispersal were different for hatchlings released in the morning and late afternoon at two sites. Comparisons of the dispersal of naïve and translocated experienced hatchlings (those with previous exposure to environmental cues) suggest that hatchlings develop a sun compass within 2 days of emergence from nests. Based on all nonrandom dispersals of hatchlings at arenas, the estimated maximum perception distance of hatchlings was 325 m. In some situations, forest succession, agriculture activities, and introduction of pine trees may increase risks faced by hatchlings dispersing from nests by reducing their ability to find wetlands.

scholarly journals DINAMIKA PENENTUAN ARAH KIBLAT

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Dwi Putra Jaya
Keyword(s):  
The Sun ◽  
Sun Compass ◽  
Early Stages ◽  
The Temple ◽  
The Way

Abstract: To know the direction of Qiblah is already a lot of tools. Can be through measurements, can also use a prayer rug that has a compass Qiblah direction that is widely used in mosques. However, in order to attain the virtue of charity, it is necessary to make sure that the direction approached in the direction precisely facing the Temple. The way of determining the direction of the Qiblah for mosques has evolved in accordance with the development of knowledge held by Islamic societies, in the early stages using a very simple way, then progressed by using tools to measure it, among them Trigonometry, the shadow of the sun, compass magnet, transparent compass, compass Qibla, protractor, Rubu ‘mujayyab, string or thread, stick istiwa’ and waterpas, lot, elbow.

scholarly journals Egocentric information helps desert ants to navigate around familiar obstacles

2001 ◽  
Vol 204 (24) ◽  
pp. 4177-4184
Author(s):  
Sonja Bisch-Knaden ◽  
Rüdiger Wehner
Keyword(s):  
Test Area ◽  
Field Of View ◽  
Visual Guidance ◽  
Directional Information ◽  
Visual Cue ◽  
Desert Ants ◽  
Constant Angle ◽  
Nesting Sites ◽  
Cataglyphis Fortis ◽  
Local Cues

SUMMARY Homing ants have been shown to associate directional information with familiar landmarks. The sight of these local cues might either directly guide the path of the ant or it might activate a landmark-based vector that points towards the goal position. In either case, the ants define their courses within allocentric systems of reference. Here, we show that desert ants, Cataglyphis fortis, forced to run along a devious path can use egocentric information as well. The ants were trained to deviate from their straight homebound course by a wide inconspicuous barrier that was placed between the feeding and nesting sites. At a distant test area, the ants were confronted with an identical barrier rotated through 45°. After passing the edge of the obstacle, the ants did not proceed in the trained direction, defined by the skylight compass, but rotated their courses to match the rotation of the barrier. Visual guidance could be excluded because, as soon as the ants turned around the end of the barrier, the visual cue it provided vanished from their field of view. Instead, the ants must have maintained a constant angle relative to their previous walking trajectory along the obstacle and, hence, must have determined their new vector course in an egocentric way.

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