Understanding the Structural and Developmental Aspect of Simple
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Animal Eyes and the Darwinian Theory of the Evolution of the Human
Animal Eyes We can learn a lot from the wonder of, and the wonder in, animal eyes. Aldo Leopold a pioneer in the conservation movement did. He wrote in Thinking like a Mountain, “We reached the old wolf in time to watch a fierce green fire dying in her eyes. I realized then, and have known ever since, that there was something new to me in those eyes – something known only to her and to the mountain. I was young then, and full of trigger-itch; I thought that because fewer wolves meant more deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view.” For Aldo Leopold, the green fire in the wolf’s eyes symbolized a new way of seeing our place in the world, and with his new insight, he provided a new ethical perspective for the environmental movement. http://vimeo.com/8669977 Light contains information about the environment, and animals without eyes can make use of the information provided by environmental light without forming an image. Euglena, a single-celled organism that did not fit nicely into Carl Linnaeus’ two kingdom system of classification, quite clearly responds to light. Its plant-like nature responds to light by photosynthesizing and its animal- like nature responds to light by moving to and staying in the light. Light causes an increase in the swimming speed, a response known as 165 photokinesis. Light also causes another response in Euglena, known as an accumulation response (phototaxis). -
Lafranca Moth Article.Pdf
What you may not know about... MScientific classificationoths Kingdom: Animalia Phylum: Arthropoda Class: Insecta Photography and article written by Milena LaFranca order: Lepidoptera [email protected] At roughly 160,000, there are nearly day or nighttime. Butterflies are only above: scales on moth wing, shot at 2x above: SEM image of individual wing scale, 1500x ten times the number of species of known to be diurnal insects and moths of moths have thin butterfly-like of microscopic ridges and bumps moths compared to butterflies, which are mostly nocturnal insects. So if the antennae but they lack the club ends. that reflect light in various angles are in the same order. While most sun is out, it is most likely a butterfly and Moths utilize a wing-coupling that create iridescent coloring. moth species are nocturnal, there are if the moon is out, it is definitely a moth. mechanism that includes two I t i s c o m m o n f o r m o t h w i n g s t o h a v e some that are crepuscular and others A subtler clue in butterfly/moth structures, the retinaculum and patterns that are not in the human that are diurnal. Crepuscular meaning detection is to compare the placement the frenulum. The frenulum is a visible light spectrum. Moths have that they are active during twilight of their wings at rest. Unless warming spine at the base of the hind wing. the ability to see in ultra-violet wave hours. Diurnal themselves, The retinaculum is a loop on the lengths. -
Seeing Through Moving Eyes
bioRxiv preprint doi: https://doi.org/10.1101/083691; this version posted June 1, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Seeing through moving eyes - microsaccadic information sampling provides 2 Drosophila hyperacute vision 3 4 Mikko Juusola1,2*‡, An Dau2‡, Zhuoyi Song2‡, Narendra Solanki2, Diana Rien1,2, David Jaciuch2, 5 Sidhartha Dongre2, Florence Blanchard2, Gonzalo G. de Polavieja3, Roger C. Hardie4 and Jouni 6 Takalo2 7 8 1National Key laboratory of Cognitive Neuroscience and Learning, Beijing, Beijing Normal 9 University, Beijing 100875, China 10 2Department of Biomedical Science, University of Sheffield, Sheffield S10 T2N, UK 11 3Champalimaud Neuroscience Programme, Champalimaud Center for the Unknown, Lisbon, 12 Portugal 13 4Department of Physiology Development and Neuroscience, Cambridge University, Cambridge CB2 14 3EG, UK 15 16 *Correspondence to: [email protected] 17 ‡ Equal contribution 18 19 Small fly eyes should not see fine image details. Because flies exhibit saccadic visual behaviors 20 and their compound eyes have relatively few ommatidia (sampling points), their photoreceptors 21 would be expected to generate blurry and coarse retinal images of the world. Here we 22 demonstrate that Drosophila see the world far better than predicted from the classic theories. 23 By using electrophysiological, optical and behavioral assays, we found that R1-R6 24 photoreceptors’ encoding capacity in time is maximized to fast high-contrast bursts, which 25 resemble their light input during saccadic behaviors. Whilst over space, R1-R6s resolve moving 26 objects at saccadic speeds beyond the predicted motion-blur-limit. -
Introduction; Environment & Review of Eyes in Different Species
The Biological Vision System: Introduction; Environment & Review of Eyes in Different Species James T. Fulton https://neuronresearch.net/vision/ Abstract: Keywords: Biological, Human, Vision, phylogeny, vitamin A, Electrolytic Theory of the Neuron, liquid crystal, Activa, anatomy, histology, cytology PROCESSES IN BIOLOGICAL VISION: including, ELECTROCHEMISTRY OF THE NEURON Introduction 1- 1 1 Introduction, Phylogeny & Generic Forms 1 “Vision is the process of discovering from images what is present in the world, and where it is” (Marr, 1985) ***When encountering a citation to a Section number in the following material, the first numeric is a chapter number. All cited chapters can be found at https://neuronresearch.net/vision/document.htm *** 1.1 Introduction While the material in this work is designed for the graduate student undertaking independent study of the vision sensory modality of the biological system, with a certain amount of mathematical sophistication on the part of the reader, the major emphasis is on specific models down to specific circuits used within the neuron. The Chapters are written to stand-alone as much as possible following the block diagram in Section 1.5. However, this requires frequent cross-references to other Chapters as the analyses proceed. The results can be followed by anyone with a college degree in Science. However, to replicate the (photon) Excitation/De-excitation Equation, a background in differential equations and integration-by-parts is required. Some background in semiconductor physics is necessary to understand how the active element within a neuron operates and the unique character of liquid-crystalline water (the backbone of the neural system). The level of sophistication in the animal vision system is quite remarkable. -
Circadian Clocks in Crustaceans: Identified Neuronal and Cellular Systems
Circadian clocks in crustaceans: identified neuronal and cellular systems Johannes Strauss, Heinrich Dircksen Department of Zoology, Stockholm University, Svante Arrhenius vag 18A, S-10691 Stockholm, Sweden TABLE OF CONTENTS 1. Abstract 2. Introduction: crustacean circadian biology 2.1. Rhythms and circadian phenomena 2.2. Chronobiological systems in Crustacea 2.3. Pacemakers in crustacean circadian systems 3. The cellular basis of crustacean circadian rhythms 3.1. The retina of the eye 3.1.1. Eye pigment migration and its adaptive role 3.1.2. Receptor potential changes of retinular cells in the electroretinogram (ERG) 3.2. Eyestalk systems and mediators of circadian rhythmicity 3.2.1. Red pigment concentrating hormone (RPCH) 3.2.2. Crustacean hyperglycaemic hormone (CHH) 3.2.3. Pigment-dispersing hormone (PDH) 3.2.4. Serotonin 3.2.5. Melatonin 3.2.6. Further factors with possible effects on circadian rhythmicity 3.3. The caudal photoreceptor of the crayfish terminal abdominal ganglion (CPR) 3.4. Extraretinal brain photoreceptors 3.5. Integration of distributed circadian clock systems and rhythms 4. Comparative aspects of crustacean clocks 4.1. Evolution of circadian pacemakers in arthropods 4.2. Putative clock neurons conserved in crustaceans and insects 4.3. Clock genes in crustaceans 4.3.1. Current knowledge about insect clock genes 4.3.2. Crustacean clock-gene 4.3.3. Crustacean period-gene 4.3.4. Crustacean cryptochrome-gene 5. Perspective 6. Acknowledgements 7. References 1. ABSTRACT Circadian rhythms are known for locomotory and reproductive behaviours, and the functioning of sensory organs, nervous structures, metabolism and developmental processes. The mechanisms and cellular bases of control are mainly inferred from circadian phenomenologies, ablation experiments and pharmacological approaches. -
Vision-In-Arthropoda.Pdf
Introduction Arthropods possess various kinds of sensory structures which are sensitive to different kinds of stimuli. Arthropods possess simple as well as compound eyes; the latter evolved in Arthropods and are found in no other group of animals. Insects that possess both types of eyes: simple and compound. Photoreceptors: sensitive to light Photoreceptor in Arthropoda 1. Simple Eyes 2. Compound Eyes 1. Simple Eyes in Arthropods - Ocelli The word ocelli are derived from the Latin word ocellus which means little eye. Ocelli are simple eyes which comprise of single lens for collecting and focusing light. Arthropods possess two kinds of ocelli a) Dorsal Ocelli b) Lateral Ocelli (Stemmata) Dorsal Ocellus - Dorsal ocelli are found on the dorsal or front surface of the head of nymphs and adults of several hemimetabolous insects. These are bounded by compound eyes on lateral sides. Dorsal ocelli are not present in those arthropods which lack compound eyes. • Dorsal ocellus has single corneal lens which covers a number of sensory rod- like structures, rhabdome. • The ocellar lens may be curved, for example in bees, locusts and dragonflies; or flat as in cockroaches. • It is sensitive to a wide range of wavelengths and shows quick response to changes in light intensity. • It cannot form an image and is unable to recognize the object. Lateral Ocellus - Stemmata Lateral ocelli, It is also known as stemmata. They are the only eyes in the larvae of holometabolous and certain adult insects such as spring tails, silver fish, fleas and stylops. These are called lateral eyes because they are always present in the lateral region of the head. -
The Evolution of Eyes
Annual Reviews www.annualreviews.org/aronline Annu. Reo. Neurosci. 1992. 15:1-29 Copyright © 1992 by Annual Review~ Inc] All rights reserved THE EVOLUTION OF EYES Michael F. Land Neuroscience Interdisciplinary Research Centre, School of Biological Sciences, University of Sussex, Brighton BN19QG, United Kingdom Russell D. Fernald Programs of HumanBiology and Neuroscience and Department of Psychology, Stanford University, Stanford, California 94305 KEYWORDS: vision, optics, retina INTRODUCTION: EVOLUTION AT DIFFERENT LEVELS Since the earth formed more than 5 billion years ago, sunlight has been the most potent selective force to control the evolution of living organisms. Consequencesof this solar selection are most evident in eyes, the premier sensory outposts of the brain. Becauseorganisms use light to see, eyes have evolved into manyshapes, sizes, and designs; within these structures, highly conserved protein molecules for catching photons and bending light rays have also evolved. Although eyes themselves demonstrate manydifferent solutions to the problem of obtaining an image--solutions reached rela- by University of California - Berkeley on 09/02/08. For personal use only. tively late in evolution--some of the molecules important for sight are, in fact, the same as in the earliest times. This suggests that once suitable Annu. Rev. Neurosci. 1992.15:1-29. Downloaded from arjournals.annualreviews.org biochemical solutions are found, they are retained, even though their "packaging"varies greatly. In this review, we concentrate on the diversity of eye types and their optical evolution, but first we consider briefly evolution at the more fundamental levels of molecules and cells. Molecular Evolution The opsins, the protein componentsof the visual pigments responsible for catching photons, have a history that extends well beyond the appearance of anything we would recognize as an eye. -
Sexual Dimorphism in the Compound Eye of Heliconius Erato:A Nymphalid Butterfly with at Least Five Spectral Classes of Photoreceptor Kyle J
© 2016. Published by The Company of Biologists Ltd | Journal of Experimental Biology (2016) 219, 2377-2387 doi:10.1242/jeb.136523 RESEARCH ARTICLE Sexual dimorphism in the compound eye of Heliconius erato:a nymphalid butterfly with at least five spectral classes of photoreceptor Kyle J. McCulloch1, Daniel Osorio2 and Adriana D. Briscoe1,* ABSTRACT birds and bees, there is little variation in photoreceptor spectral Most butterfly families expand the number of spectrally distinct sensitivities between species within a given clade (Osorio and photoreceptors in their compound eye by opsin gene duplications Vorobyev, 2005; Bloch, 2015), or between sexes. Aquatic taxa together with lateral filter pigments; however, most nymphalid genera including teleost fish (Carleton and Kocher, 2001; Bowmaker and have limited diversity, with only three or four spectral types of Hunt, 2006) and stomatopods (Cronin and Marshall, 1989; Porter photoreceptor. Here, we examined the spatial pattern of opsin et al., 2009) do have substantial spectral diversity of photoreceptors expression and photoreceptor spectral sensitivities in Heliconius between related species, which can often be related to the spectral erato, a nymphalid with duplicate ultraviolet opsin genes, UVRh1 and variation in ambient illumination in water. Among terrestrial UVRh2. We found that the H. erato compound eye is sexually animals, dragonflies (Futahashi et al., 2015) and butterflies dimorphic. Females express the two UV opsin proteins in separate (Briscoe, 2008) are known for the diversity of their photoreceptor photoreceptors, but males do not express UVRh1. Intracellular spectral sensitivities, but the evolutionary causes and physiological recordings confirmed that females have three short wavelength- significance of these differences remain unclear, and there is limited λ ∼ evidence for sexual dimorphism in photoreceptor spectral sensitive photoreceptors ( max=356, 390 and 470 nm), while males λ ∼ sensitivities (but see below). -
Attention and Individual Behavioural Variation in Small-Brained Animals – Using Bumblebees and Zebrafish As Model Systems
Attention and individual behavioural variation in small-brained animals – using bumblebees and zebrafish as model systems Mu-Yun Wang Thesis submitted for the degree of Doctor of Philosophy Queen Mary, University of London 2013 1 Abstract A vital ability for an animal is to filter the constant flow of sensory input from the environment to focus on the most important information. Attention is used to prioritize sensory input for adaptive responses. The role of attention in visual search has been studied extensively in human and non-human primates, but is much less studied in other animals. We looked at attentional mechanisms, especially selective and divided attention where animals focus on multiple cues at the same time, using a visual search paradigm. We targeted bumblebee and zebrafish as model species because they are widely used as tractable models of information processing in comparatively small brains. Bees were required to forage from target and distractor flowers in the presence of predators. We found that bees could selectively attend to certain dimension of the stimuli, and divide their attention to both visual foraging search and predator avoidance tasks simultaneously. Furthermore, bees showed consistent individual differences in foraging strategy; ‘careful’ and ‘impulsive’ strategies exist in individuals of the same colony. From the calculation of foraging rate, it is shown that the best strategy may depend on environmental conditions. We applied a similar behavioural paradigm to zebrafish and found speed-accuracy tradeoffs and consistent individual behavioural differences. We therefore continued to test how individuality influences group choices. In pairs of careful and impulsive fish, the consensus decision is close to the strategy of the careful individual. -
Sexual Dimorphism and Light/Dark Adaptation in the Compound Eyes of Male and Female Acentria Ephemerella (Lepidoptera: Pyraloidea: Crambidae)
Eur. J. Entomol. 104: 459–470, 2007 http://www.eje.cz/scripts/viewabstract.php?abstract=1255 ISSN 1210-5759 Sexual dimorphism and light/dark adaptation in the compound eyes of male and female Acentria ephemerella (Lepidoptera: Pyraloidea: Crambidae) TING FAN (STANLEY) LAU1, ELISABETH MARIA GROSS2 and VICTOR BENNO MEYER-ROCHOW1,3 1Faculty of Engineering and Sciences, Jacobs University Bremen, P.O.Box 750561, D-28725 Bremen, Germany 2Limnological Institute, University of Konstanz, P.O. Box M659, D-78457 Konstanz, Germany 3Department of Biology (Zoological Museum), University of Oulu, P.O.Box 3000, SF-90014 Oulu, Finland; e-mail: [email protected] and [email protected] Key words. Pyraloidea, Crambidae, compound eye, photoreception, vision, retina, sexual dimorphism, polarization sensitivity, dark/light adaptation, photoreceptor evolution Abstract. In the highly sexual-dimorphic nocturnal moth, Acentria ephemerella Denis & Schiffermüller 1775, the aquatic and win- gless female possesses a refracting superposition eye, whose gross structural organization agrees with that of the fully-winged male. The possession of an extensive corneal nipple array, a wide clear-zone in combination with a voluminous rhabdom and a reflecting tracheal sheath are proof that the eyes of both sexes are adapted to function in a dimly lit environment. However, the ommatidium of the male eye has statistically significantly longer dioptric structures (i.e., crystalline cones) and light-perceiving elements (i.e., rhab- doms), as well as a much wider clear-zone than the female. Photomechanical changes upon light/dark adaptation in both male and female eyes result in screening pigment translocations that reduce or dilate ommatidial apertures, but because of the larger number of smaller facets of the male eye in combination with the structural differences of dioptric apparatus and retina (see above) the male eye would enjoy superior absolute visual sensitivity under dim conditions and a greater resolving power and ability to detect movement during the day. -
Factors Affecting Counterillumination As a Cryptic Strategy
Reference: Biol. Bull. 207: 1–16. (August 2004) © 2004 Marine Biological Laboratory Propagation and Perception of Bioluminescence: Factors Affecting Counterillumination as a Cryptic Strategy SO¨ NKE JOHNSEN1,*, EDITH A. WIDDER2, AND CURTIS D. MOBLEY3 1Biology Department, Duke University, Durham, North Carolina 27708; 2Marine Science Division, Harbor Branch Oceanographic Institution, Ft. Pierce, Florida 34946; and 3Sequoia Scientific Inc., Bellevue, Washington 98005 Abstract. Many deep-sea species, particularly crusta- was partially offset by the higher contrast attenuation at ceans, cephalopods, and fish, use photophores to illuminate shallow depths, which reduced the sighting distance of their ventral surfaces and thus disguise their silhouettes mismatches. This research has implications for the study of from predators viewing them from below. This strategy has spatial resolution, contrast sensitivity, and color discrimina- several potential limitations, two of which are examined tion in deep-sea visual systems. here. First, a predator with acute vision may be able to detect the individual photophores on the ventral surface. Introduction Second, a predator may be able to detect any mismatch between the spectrum of the bioluminescence and that of the Counterillumination is a common form of crypsis in the background light. The first limitation was examined by open ocean (Latz, 1995; Harper and Case, 1999; Widder, modeling the perceived images of the counterillumination 1999). Its prevalence is due to the fact that, because the of the squid Abralia veranyi and the myctophid fish Cera- downwelling light is orders of magnitude brighter than the toscopelus maderensis as a function of the distance and upwelling light, even an animal with white ventral colora- visual acuity of the viewer. -
RESEARCH ARTICLE Oxidative Stress, Photodamage and the Role of Screening Pigments in Insect Eyes
3200 The Journal of Experimental Biology 216, 3200-3207 © 2013. Published by The Company of Biologists Ltd doi:10.1242/jeb.082818 RESEARCH ARTICLE Oxidative stress, photodamage and the role of screening pigments in insect eyes Teresita C. Insausti, Marion Le Gall and Claudio R. Lazzari* Institut de Recherche sur la Biologie de l’Insecte, UMR 7261 CNRS – Université François Rabelais, Tours, France *Author for correspondence ([email protected]) SUMMARY Using red-eyed mutant triatomine bugs (Hemiptera: Reduvidae), we tested the hypothesis of an alternative function of insect screening pigments against oxidative stress. To test our hypothesis, we studied the morphological and physiological changes associated with the mutation. We found that wild-type eyes possess a great amount of brown and red screening pigment inside the primary and secondary pigment cells as well as in the retinular cells. Red-eyed mutants, however, have only scarce red granules inside the pigmentary cells. We then compared the visual sensitivity of red-eyed mutants and wild types by measuring the photonegative responses of insects reared in light:dark cycles [12h:12h light:dark (LD)] or constant darkness (DD). Finally, we analyzed both the impact of oxidative stress associated with blood ingestion and photodamage of UV light on the eye retina. We found that red-eyed mutants reared in DD conditions were the most sensitive to the light intensities tested. Retinae of LD- reared mutants were gradually damaged over the life cycle, while for DD-reared insects retinae were conserved intact. No retinal damage was observed in non-fed mutants exposed to UV light for 2weeks, whereas insects fed on blood prior to UV exposure showed clear signs of retinal damage.