Example Of Mimicry Research Articles

Multiple inducers of endothelial NOS (eNOS) dysfunction in sickle cell disease.

A characteristic aspect of the robust, systemic inflammatory state in sickle cell disease is dysfunction of endothelial nitric oxide synthase (eNOS). We identify 10 aberrant endothelial cell inputs, present in the specific sickle context, that are known to have the ability to cause eNOS dysfunction. These are: endothelial arginase depletion, asymmetric dimethylarginine, complement activation, endothelial glycocalyx degradation, free fatty acids, inflammatory mediators, microparticles, oxidized low density lipoproteins, reactive oxygen species, and Toll‐like receptor 4 signaling ligands. The effect of true eNOS dysfunction on clinical testing using flow‐mediated dilation can be simulated by two known examples of endothelial dysfunction mimicry (hemoglobin consumption of NO; and oxidation of smooth muscle cell soluble guanylate cyclase). This lends ambiguity to interpretation of such clinical testing. The presence of these multiple perturbing factors argues that a therapeutic approach targeting only a single injurious endothelial input (or either example of mimicry) would not be sufficiently efficacious. This would seem to argue for identifying therapeutics that directly protect eNOS function or application of multiple therapeutic approaches.

Mimicry in Cretaceous Bugs.

SummaryMimicry is ubiquitous in nature, yet understanding its origin and evolution is complicated by the scarcity of exceptional fossils that enable behavioral inferences about extinct animals. Here we report bizarre true bugs (Hemiptera) that closely resemble beetles (Coleoptera) from mid-Cretaceous amber. The unusual fossil bugs are described as Bersta vampirica gen. et sp. nov. and Bersta coleopteromorpha gen. et sp. nov. and are placed into a new family, Berstidae fam. nov. The specialized mouthparts of berstids indicate that they were predaceous on small arthropods. Their striking beetle-like appearance implies that they were either involved in defensive mimicry or mimicked beetles to attack unsuspecting prey. The latter would represent the first case of aggressive mimicry in the invertebrate fossil record. These findings enrich our understanding of the paleoecological associations and extinct behavioral strategies of Mesozoic insects.

The Role of Dust, Grit and Phytoliths in Tooth Wear

The threat of wear to dental enamel from hard particles of silica or silicates may have exerted great selective pressure on mammals. Increasing the hardness of enamel helps to forestall this, but capacity for variation is small because the tissue is almost entirely composed of hydroxyapatite. Hard though it is, enamel also displays considerable toughness, which is important in setting the sharpness of particles (defined as an attack angle) necessary to wear it. Added to the threat from environmental silica(tes) are phytoliths, particles of opaline silica embedded in plant tissues. We show here that phytoliths have very different properties to grit and dust and are unlikely to wear enamel. However, phytoliths would tend to fracture between teeth under similar conditions, so resembling natural agents of wear. In this context, we suggest that phytoliths could represent an example of mimicry, forming an example of a feeding deterrent operating by deceit.

Geographical variation in the benefits obtained by a coral reef fish mimic

Mimicry systems are frequently categorized by the type of benefit gained by the mimic's resemblance to its model: protection from threat, including predation (protective mimicry), and increased access to resources, including prey items (aggressive mimicry). These category types may not be mutually exclusive, and some mimics may gain more than one type of benefit. Here we examined a contentious classic textbook example of mimicry between the cleaner wrasse Labroides dimidiatus and its mimic, the sabre-toothed blenny Aspidontus taeniatus. We found that the benefit obtained by the sabre-toothed blenny varied between four geographical locations. At the Great Barrier Reef, in Indonesia and in the Red Sea, it rarely attacked reef fish victims, but instead relied on other food sources such as substrate items, damselfish eggs and tubeworms. Here, the main function of the mimicry system could be to protect the sabre-toothed blenny from predation (protective mimicry) and was consistent with a previous study in Japan. However, in French Polynesia, the sabre-toothed blenny aggressively attacked reef fish frequently, and potential victims were more likely to pose to solicit a cleaning interaction. Diet analysis from individuals in French Polynesia indicated material was gleaned from the surface of fish, including large pieces of fin, implying an increase in the benefits obtained from attacking reef fish (aggressive mimicry). This study provides a potential second example of a mimicry system in which multiple types of benefits are gained by a mimic, and importantly, that the benefits obtained by the mimic vary between different environmental conditions and/or geographical locations. This may have important implications for the maintenance and evolution of mimicry systems and may reflect different stages of an arms race with potential victims.

Miming Manu: Women, Authority and Mimicry in a Tantric Context

This paper proposes an example of mimicry as an instance of intertextuality across genres, revealing a complex social response to normative, orthodox attitudes towards women through a close analysis of two very different types of male-authored religious texts from India, Tantric texts and a particularly famous law book, Manava Dharma Śāstra. I argue that mimicry functions to undermine a normative stance towards women by appropriating and subverting the well-known verse from Manu's Law Book that states that women should not be permitted any independence from their male guardians. In this case, this verse is reformulated to reverse the meaning it originally had in Manu's Dharma Śāstra, communicating a very different attitude towards women. This Tantric subversion of Manu suggests not only that elements of legal texts impacted on non-dominant populations through imitation and circulation in circles outside of expected Brahmanical orthodoxy, but also that textual satire via appropriation of these verses may have at times offered resistance, contesting the political assertions of a normative view.

First record of potential Batesian mimicry in an elasmobranch: juvenile zebra sharks mimic banded sea snakes?

Various forms of mimicry have been recorded in a large number of marine fishes; however, there have been no records of mimicry for any elasmobranch species. We propose that the distinctly banded neonates of the zebra shark (Stegostoma fasciatum) are Batesian mimics of banded sea snakes (Elapidae). Observations of banded juveniles of S. fasciatum swimming close to the surface strongly resemble banded sea snakes in colour and body form as well as the undulatory swimming movements. Sea snakes are venomous and are known to defend themselves against predators. Although several shark species prey on them, most species appear to avoid sea snakes as prey items. Juvenile S. fasciatum possess a very long, single-lobed caudal fin that remarkably resembles the broad, paddle-like tail of sea snakes. This may be an adaptation enabling this species to mimic sea snakes, at least in the earliest life stages. There is a need for empirical testing of the hypothesis that juvenile S. fasciatum is a true example of Batesian mimicry, but here we provide evidence that suggests this may be the first example of mimicry in an elasmobranch species.

VII. An investigation by pedigree breeding into the polymorphism of Papilio polytes , Linn

The following paper gives an account of a series of breeding experiments which were made with the butterfly Papilio polytes , Linn., in the course of one and a half years’ research on insect polymorphism in Ceylon. In the first instance the experiments on butterflies were not limited to this species, but unfortunately all others proved refractory in captivity and were one by one discarded. More time therefore could be given to this, the only amenable species, and it was possible to make a number of observations on the habits of the imago which are suggestive in several ways, and justify a more extensive reference than is usual in papers on heredity. The first chapter of this paper, therefore, is devoted to observations on the species in captivity, especially to the pairing habits of the imagines. The second chapter deals with the results obtained from the pedigree breeding and their Mendelian interpretation, and a final chapter may be added to allow of a comparison with similar work on other species and of a summary of the conclusions to be derived from the investigation as a whole. P. polytes , as a classical example of mimicry, is too well known to need a full description here. As a subject for a detailed investigation it has peculiar advantages. It is trimorphic; this trimorphism is confined to the female sex; of the three forms of female, one resembles the male in general pattern, while the other two are mimetic, their models being P. hector , Linn., and P. aristolochiæ , Fabr. It would naturally be supposed that the female like the male would be known as the polytes ♀, but this is not the case, as one of the mimetic forms was first described under this name. To avoid confusion and to facilitate subsequent reference, the various forms of the species may be stated thus:— P. polytes ♀ form cyrus , Fabr., resembles the male. P. polytes ♀ form romulus , Cram., resembles P. hector , Linn. P. polytes ♀ form polytes , Linn., resembles P. aristolocliæ , Fabr.

The Volucellœ as Alleged Examples of Variation “almost Unique among Animals.”

IT is barren work for the parties in a controversy merely to deny each other's statements without adducing further evidence. Mr. Bateson first stated that var. mystacea did not mimic Bombus muscorum. I replied that it did, and the statement in my letter in no way depended on the case at the Royal College of Surgeons, but on a careful comparison of the insects in the Oxford Museum. It is useless for me to repeat that I regard it as an example of mimicry, not indeed equal to that afforded by the same fly and Bombus hortorum, but far better than many others which are generally believed to be instances of this principle (such as the resemblance of Clytus arictis, or even the resemblance—admitted by Mr. Baleson in his first letter—of Voluccella inanis, to a wasp). I therefore propose to furnish the Editor of NATURE with photographs of the Voluccellœ and humble-bees for reproduction, so that readers can judge of the matter for themselves. I will do my best to obtain a negative which shows the coloured bands.

The Volucellæ as Examples of Aggressive Mimicry

AN interesting point in the Volucellae as examples of aggressive mimicry is the fact that they were first used to support the teleological theories of an earlier day, and were subsequently claimed by natural selection. Thus Messrs. Kirby and Spence speak of them (Second Edition, 1817, vol. ii., p. 223) as affording “a beautiful instance of the wisdom of Providence in adapting means to their end;” and alter describing the resemblance of the flies to the bees, they continue, “Thus has the Author of nature provided that they may enter these nests and deposit their eggs undiscovered. Did these intruders venture themselves amongst the humble-bees in a less kindred form, their lives would probably pay the forfeit of their presumption.” In this theory of Providence it is hard to see where the bees come in. In 1867, A. R. Wallace published an article on “Mimicry and other Protective Resemblances among Animals”, which was in 1875 republished in his “Essays on Natural Selection.” In this essay (p. 75 of the volume) he spoke of this interpretation as the only case in which an example of mimicry had been “thought to be useful, and to have been designed as a means to a definite and intelligible purpose.” He accepts it as a product of natural selection, and since that time it has been constantly used as a well-known example of this principle, so well known, indeed, that the history of it became unnecessary in any publication where space was an object.

Mimicry in Birds

ON the evening of the 24th inst. my attention was attracted by an interesting example of mimicry in the case of the starling. The first thing which attracted my attention was hearing the cry of a blackbird in distress, and on looking round, the only bird to be seen was a solitary starling, which, when I first observed it, was uttering its own note; but almost immediately thereafter it began to whistle loudly in imitation of the blackbird. After this, for the space of about half an hour, it kept up a constant succession of notes in mimicry of the chaffinch and sparrow, always, however, using its own note for the space of about half a minute between each change. I may add that it did not seem to have any particular order in which it repeated the various notes.