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Scale (insect Anatomy)
Scales are present on the bodies of various insects. A notable example are Lepidoptera, the insect order comprising moths and butterflies, which has scales on their wings and also on the head, parts of the thorax and abdomen as well as parts of the genitalia. The name is derived from Ancient Greek λεπίδος (scale) and πτερόν (wing).Scoble, M.J. (2005). ''The Lepidoptera: Form, Function, and Diversity''. Page 63. Accessed through Google books on 21 Aug 200/ref> The Trichoptera (caddisflies) which are a sister group of the Lepidoptera have scales, but also possess caudal cerci on the abdomen, a feature absent in the Lepidoptera.Powell, Jerry A. Lepidoptera (pp. 631-664) in Resh, V. H. & R. T. Cardé (Editors) 2003. Encyclopedia of Insects. Academic Press. Beetles of family Dermestidae also commonly have scales.Byrd, Jason. Castner, James (2001)Forensic Entomology: The Utility of Arthropods in Legal Investigations/ref> Morphology The morphology of scales has been stu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Morphology Of Lepidoptera
The external morphology of Lepidoptera is the physiological structure of the bodies of insects belonging to the order Lepidoptera, also known as butterflies and moths. Lepidoptera are distinguished from other orders by the presence of scales on the external parts of the body and appendages, especially the wings. Butterflies and moths vary in size from microlepidoptera only a few millimetres long, to a wingspan of many inches such as the Atlas moth. Comprising over 160,000 described species, the Lepidoptera possess variations of the basic body structure which has evolved to gain advantages in adaptation and distribution. Lepidopterans undergo complete metamorphosis, going through a four-stage life cycle: egg, larva or caterpillar, pupa or chrysalis, and imago (plural: ''imagines'') / adult. The larvae – caterpillars – have a toughened ( sclerotised) head capsule, chewing mouthparts, and a soft body, that may have hair-like or other projections, three pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lift To Drag Ratio
In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the lift generated by an aerodynamic body such as an aerofoil or aircraft, divided by the aerodynamic drag caused by moving through air. It describes the aerodynamic efficiency under given flight conditions. The L/D ratio for any given body will vary according to these flight conditions. For an aerofoil wing or powered aircraft, the L/D is specified when in straight and level flight. For a glider it determines the glide ratio, of distance travelled against loss of height. The term is calculated for any particular airspeed by measuring the lift generated, then dividing by the drag at that speed. These vary with speed, so the results are typically plotted on a 2-dimensional graph. In almost all cases the graph forms a U-shape, due to the two main components of drag. The L/D may be calculated using computational fluid dynamics or computer simulation. It is measured empirically by testing in a wind tunnel or in free flight te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Eisner
Thomas Eisner (June 25, 1929 – March 25, 2011) was a German-American entomologist and ecologist, known as the "father of chemical ecology." He was a Jacob Gould Schurman Professor of Chemical Ecology at Cornell University, and Director of the Cornell Institute for Research in Chemical Ecology (CIRCE). He was a world authority on animal behavior, ecology, and evolution, and, together with his Cornell colleague Jerrold Meinwald, was one of the pioneers of chemical ecology, the discipline dealing with the chemical interactions of organisms. He was author or co-author of some 400 scientific articles and seven books. Personal life Thomas Eisner was born on June 25, 1929, in Berlin, Germany. His father, Hans Eisner, was a chemist of Jewish origin, and a coworker of Fritz Haber at the Kaiser Wilhelm Institute for Electrochemistry in Berlin; he later held a chair for chemistry at Cornell. His mother, Margarete Heil-Eisner, was an artist. Escaping the Nazi regime, the family moved to B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrmecophily
Myrmecophily ( , ) is the term applied to positive interspecies associations between ants and a variety of other organisms, such as plants, other arthropods, and fungi. Myrmecophily refers to mutualistic associations with ants, though in its more general use, the term may also refer to commensal or even parasitic interactions. The term "myrmecophile" is used mainly for animals that associate with ants. An estimated 10,000 species of ants (Formicidae) are known, with a higher diversity in the tropics.B. Holldobler and E.O. Wilson, The Ants, Cambridge, Massachusetts: The Belknap Press of Harvard University Press, 1990. In most terrestrial ecosystems, ants are ecologically and numerically dominant, being the main invertebrate predators. As a result, ants play a key role in controlling arthropod richness, abundance, and community structure.K. Fiedler, B. Holldobler, and P. Seufert, "Butterflies and ants: The communicative domain," Cellular and molecular life sciences, vol. 52, 1996 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Müllerian Mimicry
Müllerian mimicry is a natural phenomenon in which two or more well-defended species, often foul-tasting and sharing common predators, have come to mimic each other's honest warning signals, to their mutual benefit. The benefit to Müllerian mimics is that predators only need one unpleasant encounter with one member of a set of Müllerian mimics, and thereafter avoid all similar coloration, whether or not it belongs to the same species as the initial encounter. It is named after the German naturalist Fritz Müller, who first proposed the concept in 1878, supporting his theory with the first mathematical model of frequency-dependent selection, one of the first such models anywhere in biology. Müllerian mimicry was first identified in tropical butterflies that shared colourful wing patterns, but it is found in many groups of insects such as bumblebees, and other animals including poison frogs and coral snakes. The mimicry need not be visual; for example, many snakes share a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batesian Mimicry
Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both. It is named after the English naturalist Henry Walter Bates, after his work on butterflies in the rainforests of Brazil. Batesian mimicry is the most commonly known and widely studied of mimicry complexes, such that the word mimicry is often treated as synonymous with Batesian mimicry. There are many other forms however, some very similar in principle, others far separated. It is often contrasted with Müllerian mimicry, a form of mutually beneficial convergence between two or more harmful species. However, because the mimic may have a degree of protection itself, the distinction is not absolute. It can also be contrasted with functionally different forms of mimicry. Perhaps the sharpest contrast here is with aggressive mimicry where a predator or parasite mimics a harmless species, avoiding detection and improving its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aposematism
Aposematism is the advertising by an animal to potential predators that it is not worth attacking or eating. This unprofitability may consist of any defences which make the prey difficult to kill and eat, such as toxicity, venom, foul taste or smell, sharp spines, or aggressive nature. These advertising signals may take the form of conspicuous coloration, sounds, odours, or other perceivable characteristics. Aposematic signals are beneficial for both predator and prey, since both avoid potential harm. The term was coined in 1877 by Edward Bagnall Poulton for Alfred Russel Wallace's concept of warning coloration. Aposematism is exploited in Müllerian mimicry, where species with strong defences evolve to resemble one another. By mimicking similarly coloured species, the warning signal to predators is shared, causing them to learn more quickly at less of a cost. A genuine aposematic signal that a species actually possesses chemical or physical defences is not the only way to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Insulation
Thermal insulation is the reduction of heat transfer (i.e., the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials. Heat flow is an inevitable consequence of contact between objects of different temperature. Thermal insulation provides a region of insulation in which thermal conduction is reduced, creating a thermal break or thermal barrier, or thermal radiation is reflected rather than absorbed by the lower-temperature body. The insulating capability of a material is measured as the inverse of thermal conductivity (k). Low thermal conductivity is equivalent to high insulating capability ( resistance value). In thermal engineering, other important properties of insulating materials are product density (ρ) and specific heat capacity (c). Definition T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimicry
In evolutionary biology, mimicry is an evolved resemblance between an organism and another object, often an organism of another species. Mimicry may evolve between different species, or between individuals of the same species. Often, mimicry functions to protect a species from predators, making it an anti-predator adaptation. Mimicry evolves if a receiver (such as a predator) perceives the similarity between a mimic (the organism that has a resemblance) and a model (the organism it resembles) and as a result changes its behaviour in a way that provides a selective advantage to the mimic. The resemblances that evolve in mimicry can be visual, acoustic, chemical, tactile, or electric, or combinations of these sensory modalities. Mimicry may be to the advantage of both organisms that share a resemblance, in which case it is a form of mutualism; or mimicry can be to the detriment of one, making it parasitic or competitive. The evolutionary convergence between groups is driven by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the battledress of a modern soldier, and the leaf-mimic katydid's wings. A third approach, motion dazzle, confuses the observer with a conspicuous pattern, making the object visible but momentarily harder to locate, as well as making general aiming easier. The majority of camouflage methods aim for crypsis, often through a general resemblance to the background, high contrast disruptive coloration, eliminating shadow, and countershading. In the open ocean, where there is no background, the principal methods of camouflage are transparency, silvering, and countershading, while the ability to produce light is among other things used for counter-illumination on the undersides of cephalopods such as squid. Some animals, such as chameleons and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
