scholarly journals Ultraviolet polarization vision in fishes: possible mechanisms for coding e–vector

2000 ◽  
Vol 355 (1401) ◽  
pp. 1187-1190 ◽  
Author(s):  
Craig W. Hawryshyn

Polarization vision in vertebrates has been marked with significant controversy over recent decades. In the last decade, however, models from two laboratories have indicated that the spatial arrangement of photoreceptors provides the basis for polarization sensitivity.Work in my laboratory, in collaboration with I. Novales Flamarique and F. I. Harosi, has shown that polarization sensitivity depends on a well–defined square cone mosaic pattern and that the biophysical properties of the square cone mosaic probably account for polarization vision in the ultraviolet spectrum. The biophysical mechanism appears to be based on the selective reflection of axial–polarized light by the partitioning membrane, formed along the contact zone between the members of the double cones, onto neighbouring ultraviolet–sensitive cones. In this short review, I discuss the historical development of this research problem.

1996 ◽  
Vol 199 (9) ◽  
pp. 2077-2084
Author(s):  
N Shashar ◽  
P Rutledge ◽  
T Cronin

Polarization sensitivity is well documented in marine animals, but its function is not yet well understood. Of the cephalopods, squid and octopus are known to be sensitive to the orientation of polarization of incoming light. This sensitivity arises from the orthogonal orientation of neighboring photoreceptors. Electron microscopical examination of the retina of the cuttlefish Sepia officinalis L. revealed the same orthogonal structure, suggesting that cuttlefish are also sensitive to linearly polarized light. Viewing cuttlefish through an imaging polarized light analyzer revealed a prominent polarization pattern on the arms, around the eyes and on the forehead of the animals. The polarization pattern disappeared when individuals lay camouflaged on the bottom and also during extreme aggression display, attacks on prey, copulation and egg-laying behavior in females. In behavioral experiments, the responses of cuttlefish to their images reflected from a mirror changed when the polarization patterns of the reflected images were distorted. These results suggest that cuttlefish use polarization vision and display for intraspecific recognition and communication.


2021 ◽  
Vol 17 (2) ◽  
Author(s):  
Mizuki Uemura ◽  
Andrej Meglič ◽  
Myron P. Zalucki ◽  
Andrea Battisti ◽  
Gregor Belušič

Processionary caterpillars of Thaumetopoea pityocampa (in Europe) and Ochrogaster lunifer (in Australia) (Lepidoptera: Notodontidae) form single files of larvae crawling head-to-tail when moving to feeding and pupation sites. We investigated if the processions are guided by polarization vision. The heading orientation of processions could be manipulated with linear polarizing filters held above the leading caterpillar. Exposure to changes in the angle of polarization around the caterpillars resulted in corresponding changes in heading angles. Anatomical analysis indicated specializations for polarization vision of stemma I in both species. Stemma I has a rhabdom with orthogonal and aligned microvilli, and an opaque and rugged surface, which are optimizations for skylight polarization vision, similar to the dorsal rim of adult insects. Stemmata II-VI have a smooth and shiny surface and lobed rhabdoms with non-orthogonal and non-aligned microvilli; they are thus optimized for general vision with minimal polarization sensitivity. Behavioural and anatomical evidence reveal that polarized light cues are important for larval orientation and can be robustly detected with a simple visual system.


Author(s):  
Thomas W. Cronin ◽  
Sönke Johnsen ◽  
N. Justin Marshall ◽  
Eric J. Warrant

This chapter explores how polarization sensitivity is achieved in animals and how it is used in natural behavior. Arthropods are famous for their polarization sensitivity, but other animals, including vertebrates are also capable of this. A remarkable feature of some insect systems is that the sky pattern is genetically imprinted into the neural arrangements, all the way through to the central nervous system. However, celestial navigation is not the only use to which animals can put polarization vision. Other functions may include communication, contrast enhancement, and camouflage breaking. Polarized light stimuli are abundant in nature. Although no important source of light is polarized, light may become polarized when it is scattered or reflected. These two fundamental principles produce abundant polarized light in natural scenes, which explains why polarization vision is so common.


2001 ◽  
Vol 204 (14) ◽  
pp. 2383-2390 ◽  
Author(s):  
Raymon M. Glantz

SUMMARY It is proposed that polarization sensitivity at the most peripheral stages of the crayfish visual system (lamina ganglionaris and medulla externa) is used to enhance contrast and thus may contribute to motion detection in low contrast environments. The four classes of visual interneurons that exhibit polarization sensitivity (lamina monopolar cells, tangential cells, sustaining fibers and dimming fibers) are not sensitive exclusively to polarized light but also respond to unpolarized contrast stimuli. Furthermore, many of these cells and the sustaining fibers in particular exhibit a greater differential e-vector responsiveness to a changing e-vector than to e-vector variations among steady-state stimuli. While all four cell types respond modestly to light flashes at an e-vector of 90° to the preferred orientation, the dynamic response to a changing e-vector is small or absent at this orientation. Because the sustaining fibers exhibit polarization sensitivity, and they provide afferent input to a subset of optomotor neurons, the latter were also tested for polarization sensitivity. The optomotor neurons involved in compensatory reflexes for body pitch were differentially sensitive to the e-vector angle of a flash of light, with maximum responses for e-vectors near the vertical. The motor neurons also exhibited a maximum response near the vertical e-vector to a continuously rotating polarizer. Two scenarios are described in which the sensitivity to a changing e-vector can produce motion responses in the absence of intensity contrast.


Author(s):  
Manoj Kumar

Research problem and short review: Furthermore, little attention has been paid so far to how specific talent definitions, operationalization, and measures are experienced by assessees. Methodology: This multidisciplinary review aims to contribute to the establishment of a stronger theoretical basis for talent-management by presenting a conceptual framework of talent in which the definition, operationalization and measurement of talent and its relation to excellent performance is clarified. Analysis: we strongly advise organizations to incorporate self-assessment tools in their talent-identification processes. Main results: We conclude that a valid assessment of talent requires striking a balance between organizational responsibility and self-responsibility. Main contributions of your research: We systematically introduce 11 propositions into the framework, building on fragmented insights from the literature, from the fields of HRM, gifted education, positive psychology, and vocational psychology respectively.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Yuika Saito ◽  
Yoshiro Ohashi ◽  
Prabhat Verma

It is a general belief in apertureless near-field microscopy that the so-calledp-polarization configuration, where the incident light is polarized parallel to the axis of the probe, is advantageous to its counterpart, thes-polarization configuration, where the incident light is polarized perpendicular to the probe axis. While this is true for most samples under common near-field experimental conditions, there are samples which respond better to thes-polarization configuration due to their orientations. Indeed, there have been several reports that have discussed such samples. This leads us to an important requirement that the near-field experimental setup should be equipped with proper sensitivity for measurements withs-polarization configuration. This requires not only creation of effective s-polarized illumination at the near-field probe, but also proper enhancement of s-polarized light by the probe. In this paper, we have examined thes-polarization enhancement sensitivity of near-field probes by measuring and evaluating the near-field Rayleigh scattering images constructed by a variety of probes. We found that thes-polarization enhancement sensitivity strongly depends on the sharpness of the apex of near-field probes. We have discussed the efficient value of probe sharpness by considering a balance between the enhancement and the spatial resolution, both of which are essential requirements of apertureless near-field microscopy.


2011 ◽  
Vol 366 (1565) ◽  
pp. 757-762 ◽  
Author(s):  
Lydia M. Mäthger ◽  
Kenneth J. Lohmann ◽  
Colin J. Limpus ◽  
Kerstin A. Fritsches

Sea turtles undertake long migrations in the open ocean, during which they rely at least partly on magnetic cues for navigation. In principle, sensitivity to polarized light might be an additional sensory capability that aids navigation. Furthermore, polarization sensitivity has been linked to ultraviolet (UV) light perception which is present in sea turtles. Here, we tested the ability of hatchling loggerheads ( Caretta caretta ) to maintain a swimming direction in the presence of broad-spectrum polarized light. At the start of each trial, hatchling turtles, with their magnetic sense temporarily impaired by magnets, successfully established a steady course towards a light-emitting diode (LED) light source while the polarized light field was present. When the LED was removed, however, hatchlings failed to maintain a steady swimming direction, even though the polarized light field remained. Our results have failed to provide evidence for polarized light perception in young sea turtles and suggest that alternative cues guide the initial migration offshore.


2021 ◽  
Vol 13 (2) ◽  
pp. 183-199
Author(s):  
Muhamad Alnoza ◽  
Bagus Dimas Bramantio

This study discusses the application of a Sundanese cosmology called tritangtu in the arrangement of the city of Cianjur. Tritangtu is a concept of the existence of a universal triple pattern in all aspects of human life, where the focus of this discussion is tritangtu in the world or "three patterns in the world". Research on the continuation of urban planning from the Hindu-Buddhist period to the Islamic-Colonial period has basically never been done, so that is the novelty aspect of this research. The research steps used in answering the formulation of the research problem include data collection, analysis, interpretation. Based on the research conducted in this study, the city of Cianjur has applied two cosmological concepts at two levels, namely micro and macro. At the micro level, which includes the city center, it is arranged according to the cosmological rules of Islamic cities in Java. The spatial arrangement seen in the city of Cianjur at the macro level is known to follow the rules of the tritangtu concept.


2011 ◽  
Vol 366 (1565) ◽  
pp. 734-741 ◽  
Author(s):  
Vincenzo Pignatelli ◽  
Shelby E. Temple ◽  
Tsyr-Huei Chiou ◽  
Nicholas W. Roberts ◽  
Shaun P. Collin ◽  
...  

Aquatic habitats are rich in polarized patterns that could provide valuable information about the environment to an animal with a visual system sensitive to polarization of light. Both cephalopods and fishes have been shown to behaviourally respond to polarized light cues, suggesting that polarization sensitivity (PS) may play a role in improving target detection and/or navigation/orientation. However, while there is general agreement concerning the presence of PS in cephalopods and some fish species, its functional significance remains uncertain. Testing the role of PS in predator or prey detection seems an excellent paradigm with which to study the contribution of PS to the sensory assets of both groups, because such behaviours are critical to survival. We developed a novel experimental set-up to deliver computer-generated, controllable, polarized stimuli to free-swimming cephalopods and fishes with which we tested the behavioural relevance of PS using stimuli that evoke innate responses (such as an escape response from a looming stimulus and a pursuing behaviour of a small prey-like stimulus). We report consistent responses of cephalopods to looming stimuli presented in polarization and luminance contrast; however, none of the fishes tested responded to either the looming or the prey-like stimuli when presented in polarization contrast.


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