Drivers of Polymorphism Dynamics in Pygmy Grasshoppers
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Cybernetic Camouflage on Human Recipient - Visual Illusion INTERFACE
Recent Researches in Circuits, Systems, Electronics, Control & Signal Processing Cybernetic Camouflage on Human Recipient - Visual Illusion INTERFACE JIŘÍ F. URBÁNEK, JIŘÍ BARTA, JOZEF HERETÍK, JOSEF NAVRÁTIL and JAROSLAV PRŮCHA* Department of Civil Protection, Dpt of External Relations*, University of Defence, Kounicova 65, 662 10 Brno, CZECH REPUBLIC [email protected]; http://www.unob.cz Abstract: - Perceptive interface between a human recipient (observer) and visible object can be created by complicated components, domains, actors, agents and mediators. A permeability of this interfece is necessary in an environment of colaborative actors at both sides of the interface. Worse permeability or even impermeability of the interface can be asked between antagonistic enemies. Generally, a lot of various interfaces have “smash / fuzzy/ defocusing” contours but their exact definition is helpful for active and passive protection of living objects in the nature. But, the interfaces between potential enemies ask a merge of camouflage systems & processes implementing on special created interface. So, this interface needs a nature / human made camouflage mediator. This mediator must operationally mediate virtual image in real time/ space/ environment. Cybernetic camouflage implementing virtual image operating in visible range of electromagnetic vave spectrum uses data projectors for projection of image on screen interface. From above fundamental principles are created platforms of cybernetic camouflage of Czech University of Defence R&D Grant solution of National Defence Research. It deals grant Project with acronym ADAPTIV - Draft and assertion new adaptive technology for simulation and camouflage in operational environment armed forces of Czech Republic and for infrastructure protection. The resources and “how to” of this Grant asks a finding of new approaches of problems solution, especially in military environment. -
Security &Defence European
a sniper rifle 4/ 7.90 18 D 14974 E D European NO TIME? NO LAB? NO PROBLEM. & CZ TSR Security .308 WIN. EASILY IDENTIFY CHEMICAL HAZARDS WITH ES THE FLIR GRIFFIN™ G510 PORTABLE GC-MS. 2018 June/July · Defence & Security European WE KNOW THE SECRET OF ACCURATE & Defence 4/2018 LONG DISTANCE SHOOTING. The FLIR Griffin G510 is a completely self-contained GC-MS, including batteries, carrier gas, vacuum system, injector, touchscreen, and heated International Security and Defence Journal sample probe. It analyzes all phases of matter and confirms vapor-based threats in seconds, so that responders can take immediate action. ISSN 1617-7983 See FLIR in action at Eurosatory: Hall 5a Stand #A267 • OPTION TO FIT THE FOLDING HEIGHT MECHANISM ON ADJUSTABLE EITHER THE RIGHT CHEEKPIECE OR LEFT SIDE HEIGHT AND LENGTH www.euro-sd.com ADJUSTABLE • BUTTPLATE June/July 2018 HIGHLy RESISTANT TO CONTAMINATION DUE TO THE FLUTED BOLT 10-ROUND REMOVABLE METAL MAGAZINE FOR CARTRIDGES UP TO 73 MM TWO STAGE TRIGGER MECHANISM WITH THE OPTION TO SET THE TRIGGER PULL BOLT HANDLE ADAPTED FOR RELIABLE AND RAPID PISTOL GRIP WITH RELOADING WITH STORAGE SPACE AND A RIFLESCOPE ATTACHED INTERCHANGEABLE BACKSTRAPS MaxiMuM MiniMuM Barrel length Width of Weapon (MM) height of Weapon Weight Without With stoCk With stoCk With CheekpieCe With eMpty operating CaliBre Magazine CapaCity fraMe overall length (MM)* overal length (MM)** CoMpensator (MM) folded unfolded retraCted Magazine (g) teMperature range rate of tWist aCCuraCy .308 Win. 10 ALUMINIUM 1237 ± 5mm 920 ± 5mm 660 ± 1 95 ± 2 70± 2 192 ± 2 mm max. 6 300 from -50°C to + 50° 1:11“ Sub MOA FLIR Griffin™ G510 Portable GC-MS #CZGUNS www.FLIR.eu/G510 Chemical Identifier eurosatory2018 WWW.CZUB.CZ [email protected] FACEBOOK.COM/CESKAZBROJOVKA.CZ WWW.INSTAGRAM.COM/CZGUNS/ eurosatory2018 a sniper rifle 4/ 7.90 18 D 14974 E D European NO TIME? NO LAB? NO PROBLEM. -
Mimicry - Ecology - Oxford Bibliographies 12/13/12 7:29 PM
Mimicry - Ecology - Oxford Bibliographies 12/13/12 7:29 PM Mimicry David W. Kikuchi, David W. Pfennig Introduction Among nature’s most exquisite adaptations are examples in which natural selection has favored a species (the mimic) to resemble a second, often unrelated species (the model) because it confuses a third species (the receiver). For example, the individual members of a nontoxic species that happen to resemble a toxic species may dupe any predators by behaving as if they are also dangerous and should therefore be avoided. In this way, adaptive resemblances can evolve via natural selection. When this phenomenon—dubbed “mimicry”—was first outlined by Henry Walter Bates in the middle of the 19th century, its intuitive appeal was so great that Charles Darwin immediately seized upon it as one of the finest examples of evolution by means of natural selection. Even today, mimicry is often used as a prime example in textbooks and in the popular press as a superlative example of natural selection’s efficacy. Moreover, mimicry remains an active area of research, and studies of mimicry have helped illuminate such diverse topics as how novel, complex traits arise; how new species form; and how animals make complex decisions. General Overviews Since Henry Walter Bates first published his theories of mimicry in 1862 (see Bates 1862, cited under Historical Background), there have been periodic reviews of our knowledge in the subject area. Cott 1940 was mainly concerned with animal coloration. Subsequent reviews, such as Edmunds 1974 and Ruxton, et al. 2004, have focused on types of mimicry associated with defense from predators. -
Iso-Luminance Counterillumination Drove Bioluminescent Shark Radiation
OPEN Iso-luminance counterillumination drove SUBJECT AREAS: bioluminescent shark radiation ECOLOGICAL Julien M. Claes1, Dan-Eric Nilsson2, Nicolas Straube3, Shaun P. Collin4 &Je´roˆme Mallefet1 MODELLING ICHTHYOLOGY 1Laboratoire de Biologie Marine, Earth and Life Institute, Universite´ catholique de Louvain, 1348 Louvain-la-Neuve, Belgium, 2Lund ADAPTIVE RADIATION Vision Group, Lund University, 22362 Lund, Sweden, 3Department of Biology, College of Charleston, Charleston, SC 29412, USA, 4The School of Animal Biology and The Oceans Institute, The University of Western Australia, Crawley, WA 6009, Australia. Received 13 November 2013 Counterilluminating animals use ventral photogenic organs (photophores) to mimic the residual downwelling light and cloak their silhouette from upward-looking predators. To cope with variable Accepted conditions of pelagic light environments they typically adjust their luminescence intensity. Here, we found 21 February 2014 evidence that bioluminescent sharks instead emit a constant light output and move up and down in the water Published column to remain cryptic at iso-luminance depth. We observed, across 21 globally distributed shark species, 10 March 2014 a correlation between capture depth and the proportion of a ventral area occupied by photophores. This information further allowed us, using visual modelling, to provide an adaptive explanation for shark photophore pattern diversity: in species facing moderate predation risk from below, counterilluminating photophores were partially co-opted for bioluminescent signalling, leading to complex patterns. In addition Correspondence and to increase our understanding of pelagic ecosystems our study emphasizes the importance of requests for materials bioluminescence as a speciation driver. should be addressed to J.M.C. (julien.m. mong sharks, bioluminescence occurs in two shark families only, the Dalatiidae (kitefin sharks) and the [email protected]) Etmopteridae (lanternsharks), which are among the most enigmatic bioluminescent organisms1–3. -
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. -
Antipredator Deception in Terrestrial Vertebrates
Current Zoology 60 (1): 16–25, 2014 Antipredator deception in terrestrial vertebrates Tim CARO* Department of Wildlife, Fish and Conservation Biology, and Center of Population Biology, University of California, Davis, CA 95616, USA Abstract Deceptive antipredator defense mechanisms fall into three categories: depriving predators of knowledge of prey’s presence, providing cues that deceive predators about prey handling, and dishonest signaling. Deceptive defenses in terrestrial vertebrates include aspects of crypsis such as background matching and countershading, visual and acoustic Batesian mimicry, active defenses that make animals seem more difficult to handle such as increase in apparent size and threats, feigning injury and death, distractive behaviours, and aspects of flight. After reviewing these defenses, I attempt a preliminary evaluation of which aspects of antipredator deception are most widespread in amphibians, reptiles, mammals and birds [Current Zoology 60 (1): 16 25, 2014]. Keywords Amphibians, Birds, Defenses, Dishonesty, Mammals, Prey, Reptiles 1 Introduction homeotherms may increase the distance between prey and the pursuing predator or dupe the predator about the In this paper I review forms of deceptive antipredator flight path trajectory, or both (FitzGibbon, 1990). defenses in terrestrial vertebrates, a topic that has been Last, an antipredator defense may be a dishonest largely ignored for 25 years (Pough, 1988). I limit my signal. Bradbury and Vehrencamp (2011) state that “true scope to terrestrial organisms because lighting condi- deception occurs when a sender produces a signal tions in water are different from those in the air and whose reception will benefit it at the expense of the antipredator strategies often differ in the two environ- receiver regardless of the condition with which the sig- ments. -
Crypsis Decreases with Elevation in a Lizard
diversity Article Crypsis Decreases with Elevation in a Lizard Gregorio Moreno-Rueda * , Laureano G. González-Granda, Senda Reguera, Francisco J. Zamora-Camacho and Elena Melero Departamento de Zoología, Facultad de Ciencias, Universidad de Granada, E-18071 Granada, Spain; [email protected] (L.G.G.-G.); [email protected] (S.R.); [email protected] (F.J.Z.-C.); [email protected] (E.M.) * Correspondence: [email protected] Received: 7 November 2019; Accepted: 5 December 2019; Published: 7 December 2019 Abstract: Predation usually selects for visual crypsis, the colour matching between an animal and its background. Geographic co-variation between animal and background colourations is well known, but how crypsis varies along elevational gradients remains unknown. We predict that dorsal colouration in the lizard Psammodromus algirus should covary with the colour of bare soil—where this lizard is mainly found—along a 2200 m elevational gradient in Sierra Nevada (SE Spain). Moreover, we predict that crypsis should decrease with elevation for two reasons: (1) Predation pressure typically decreases with elevation, and (2) at high elevation, dorsal colouration is under conflicting selection for both crypsis and thermoregulation. By means of standardised photographies of the substratum and colourimetric measurements of lizard dorsal skin, we tested the colour matching between lizard dorsum and background. We found that, along the gradient, lizard dorsal colouration covaried with the colouration of bare soil, but not with other background elements where the lizard is rarely detected. Moreover, supporting our prediction, the degree of crypsis against bare soil decreased with elevation. Hence, our findings suggest local adaptation for crypsis in this lizard along an elevational gradient, but this local adaptation would be hindered at high elevations. -
A Fish-Eye View of Cuttlefish Camouflage Using in Situ Spectrometry
bs_bs_banner Biological Journal of the Linnean Society, 2013, 109, 535–551. With 7 figures A fish-eye view of cuttlefish camouflage using in situ spectrometry ROGER T. HANLON1*†, CHUAN-CHIN CHIAO1,2†, LYDIA M. MÄTHGER1 and N. JUSTIN MARSHALL3 1Program in Sensory Physiology and Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, USA 2Department of Life Science, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan 3Queensland Brain Institute, University of Queensland, Brisbane, Qld 4072, Australia Received 10 July 2012; revised 21 January 2013; accepted for publication 22 January 2013 Cuttlefish are colour blind yet they appear to produce colour-coordinated patterns for camouflage. Under natural in situ lighting conditions in southern Australia, we took point-by-point spectrometry measurements of camou- flaged cuttlefish, Sepia apama, and various natural objects in the immediate visual surrounds to quantify the degree of chromatic resemblance between cuttlefish and backgrounds to potential fish predators. Luminance contrast was also calculated to determine the effectiveness of cuttlefish camouflage to this information channel both for animals with or without colour vision. Uniform body patterns on a homogeneous background of algae showed close resemblance in colour and luminance; a Uniform pattern on a partially heterogeneous background showed mixed levels of resemblance to certain background features. A Mottle pattern with some disruptive components on a heterogeneous background showed general background resemblance to some benthic objects nearest the cuttlefish. A noteworthy observation for a Disruptive body pattern on a heterogeneous background was the wide range in spectral contrasts compared to Uniform and Mottle patterns. -
Computerised Aided Camouflage
NEW ASPECTS of APPLIED INFORMATICS, BIOMEDICAL ELECTRONICS & INFORMATICS and COMMUNICATIONS Computerised Aided Camouflage JIŘÍ F. URBÁNEK, JIŘÍ BARTA, JOSEF HERETÍK and JAROSLAV PRŮCHA* Department of Civil Protection, Dpt of External Relations*, University of Defence, Kounicova 65,662 10 Brno, CZECH REPUBLIC [email protected]; http://www.unob.cz Abstract: - Interface´s impermeability is important to create among antagonist´s objects in turbulent world. A lot of various interfaces have “smash” contours but their exact definition is helpful for active and passive protection of living objects in nature. The interfaces between human enemies ask camouflage systems and processes implementing military environment. Fundamental principles of nature / human made camouflage are introduced in this paper. Computer aided camouflage by means of contemporary digital cybernetics instruments is an aim of Czech University of Defence R&D Grant solution of National Defence Research Project with acronym ADAPTIV - Draft and assertion new adaptive technology for simulation and camouflage in operational environment armed forces of Czech Republic and for infrastructure protection. The resources and “how to” of this Grant asks a finding of new approaches of problems solution in military environment. The architecture of necessary systems and their technologies, representing first milestone of Grant solution, is outlined here. ADAPTIV Project tends to Active Camouflage by Computerised Aided Mimicry (CAM) implementations as autonomic outdoor computerised aided Interoper-mobile WiMAX CAM Workshop. Key-Words: - Active Camouflage by Computerised Aided Mimicry (CAM) Implementation. 1 Introduction the camouflage must be tailored to the observer. Second, Human society survival requires the most effective the camouflage must deceive the observer into making a behaviour aiming to the co-operation, collaboration, false judgment about the camouflaged object. -
Edge Enhancement Improves Disruptive
www.nature.com/scientificreports OPEN Edge enhancement improves disruptive camouflage by emphasising false edges and Received: 24 March 2016 Accepted: 03 November 2016 creating pictorial relief Published: 06 December 2016 John Egan1, Rebecca J. Sharman2, Kenneth C. Scott-Brown1 & Paul George Lovell1 Disruptive colouration is a visual camouflage composed of false edges and boundaries. Many disruptively camouflaged animals feature enhanced edges; light patches are surrounded by a lighter outline and/or a dark patches are surrounded by a darker outline. This camouflage is particularly common in amphibians, reptiles and lepidopterans. We explored the role that this pattern has in creating effective camouflage. In a visual search task utilising an ultra-large display area mimicking search tasks that might be found in nature, edge enhanced disruptive camouflage increases crypsis, even on substrates that do not provide an obvious visual match. Specifically, edge enhanced camouflage is effective on backgrounds both with and without shadows; i.e. this is not solely due to background matching of the dark edge enhancement element with the shadows. Furthermore, when the dark component of the edge enhancement is omitted the camouflage still provided better crypsis than control patterns without edge enhancement. This kind of edge enhancement improved camouflage on all background types. Lastly, we show that edge enhancement can create a perception of multiple surfaces. We conclude that edge enhancement increases the effectiveness of disruptive camouflage through mechanisms that may include the improved disruption of the object outline by implying pictorial relief. The camouflage of the copperhead snake (Agkistrodon contortrix, see Fig. 1 top-left) is composed of a pattern of irregular shapes in shades of brown; it provides an example of two ways to achieve crypsis. -
The Evolution of Crypsis When Pigmentation Is Physiologically Costly G. Moreno–Rueda
Animal Biodiversity and Conservation 43.1 (2020) 89 The evolution of crypsis when pigmentation is physiologically costly G. Moreno–Rueda Moreno–Rueda, G., 2020. The evolution of crypsis when pigmentation is physiologically costly. Animal Biodi- versity and Conservation, 43.1: 89–96, Doi: https://doi.org/10.32800/abc.2020.43.0089 Abstract The evolution of crypsis when pigmentation is physiologically costly. Predation is one of the main selective forces in nature, frequently selecting for crypsis in prey. Visual crypsis usually implies the deposition of pig- ments in the integument. However, acquisition, synthesis, mobilisation and maintenance of pigments may be physiologically costly. Here, I develop an optimisation model to analyse how pigmentation costs may affect the evolution of crypsis. The model provides a number of predictions that are easy to test empirically. It predicts that imperfect crypsis should be common in the wild, but in such a way that pigmentation is less than what is required to maximise crypsis. Moreover, optimal crypsis should be closer to “maximal” crypsis as predation risk increases and/or pigmentation costs decrease. The model predicts for intraspecific variation in optimal crypsis, depending on the difference in the predation risk or the costs of pigmentation experienced by different individuals. Key words: Predation, Pigmentation, Coloration Resumen La evolución de la cripsis cuando la pigmentación es fisiológicamente costosa. La depredación es una de las principales fuerzas de selección de la naturaleza y a menudo favorece la cripsis en las presas. Por lo general, la cripsis visual implica el depósito de pigmentos en el tegumento. Sin embargo, adquirir, sintetizar, movilizar y mantener los pigmentos puede ser fisiológicamente costoso. -
Talas, L., Baddeley, R., & Cuthill, I. (2017). Cultural Evolution of Military
Talas, L. , Baddeley, R., & Cuthill, I. (2017). Cultural evolution of military camouflage. Philosophical Transactions B: Biological Sciences, 372(1724), [20160351]. https://doi.org/10.1098/rstb.2016.0351 Peer reviewed version Link to published version (if available): 10.1098/rstb.2016.0351 Link to publication record in Explore Bristol Research PDF-document This is the author accepted manuscript (AAM). The final published version (version of record) is available online via The Royal Society at http://rstb.royalsocietypublishing.org/content/372/1724/20160351. Please refer to any applicable terms of use of the publisher. University of Bristol - Explore Bristol Research General rights This document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/red/research-policy/pure/user-guides/ebr-terms/ Talas L, Baddeley RJ, Cuthill IC. 2017 Cultural evolution of military camouflage. Phil. Trans. R. Soc. B 372: 20160351. http://dx.doi.org/10.1098/rstb.2016.0351 Cultural evolution of military camouflage Laszlo Talas1,2, Roland J. Baddeley2 and Innes C. Cuthill1 1 School of Biological Sciences, , University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK 2 School of Experimental Psychology, University of Bristol, 12A Priory Road, Bristol BS8 1TN, UK Keywords: military camouflage, defensive coloration, cultural evolution, texture analysis Submitted: 30 September 2016; Accepted 22 December 2016; Published 5 July 2017 Summary cultural, of a class of colour patterns that are widespread in nature and human design. While one has evolved and the other been For centuries, military dress exhibited vivid colours consciously created, animal and military to aid telling friend and foe apart on the battlefield camouflage are expected to show many similar [1-2].