Saturday, March 30, 2013

Praying Mantis




Description

     Mantodea (or mantisesmantes) is an order of insects that contains over 2,400 valid species and about 430 genera in 15 families worldwide in temperate and tropical habitats. Most of the species are in the family Mantidae.The English common name for any species in the order is "praying mantis", because of the typical "prayer-like" posture with folded fore-limbs, although the eggcorn "preying mantis" is sometimes used in reference to their predatory habits. In Europe and other regions, the name "praying mantis" refers to only a single species, Mantis religiosa. The closest relatives of mantises are the termites and cockroaches (order Blattodea). They are sometimes confused with phasmids (stick/leaf insects) and other elongated insects such asgrasshoppers and crickets.The name of the order mantodea is formed from the Ancient Greek words μάντις (mantis) meaning "prophet", and εἶδος (eidos) meaning "form" or "type". It was coined in 1838 by the German entomologist Hermann Burmeister.The systematics of mantises have long been disputed. Mantises, along with walking sticks, were once placed in the order Orthoptera with the cockroaches (now Blattodea) and rock crawlers (now Grylloblattodea). Kristensen (1991) combined Mantodea with the cockroaches and termites into the order Dictyoptera.

     One theory for the evolution of the group is that mantises evolved from proto-cockroaches, diverging from their common ancestors by the Cretaceous period, possibly from species likeRaphidiomimula burmitica, a predatory cockroach with mantis-like forelegs. Possibly the earliest known modern mantis is Regiata scutra, although more common (and confirmed) isSantanmantis, a stilt-legged genus, also from the Cretaceous. Like their close termite cousins, though, mantises did not become common and diverse until the early Tertiary period.


Behavior, feeding and habitat

     Most mantises are exclusively predatory and exceptions are predominantly so. Insects form their primary prey, but the diet of a mantis changes as it grows larger. In its first instar a mantis will eat small insects such as tiny flies or its own siblings. In later instars it does not or cannot profitably pursue such small prey. In the final instar as a rule the diet of the praying mantis still includes more insects than anything else, but large species of mantis have been known to prey on small scorpionslizardsfrogsbirdssnakesfish, and even rodents; they will feed on any species small enough for them to capture, but large enough to engage their attention. For example, a large mantis feeding on a bee or bug might be pestered with impunity by jackal flies and biting midges that it would readily have eaten in its first instar. Large prey tends to increase in value with the cube of its dimension: a blowfly four times as long as a jackal fly would represent a meal about 64 times as massive. When a female mantis is into her final growth spurt and is accumulating nutrients to make eggs, the largest available prey that she can manage is the most effective for her to concentrate on.

     The majority of mantises are ambush predators, but some ground and bark species will actively pursue their prey. For example, members of a few genera such as the ground mantids, EntellaLigaria and Ligariella, run over dry ground seeking prey much as tiger beetles do. Species that are predominantly ambush predators camouflage themselves and spend long periods standing perfectly still. They largely wait for their prey to stray within reach, but most mantises will chase tempting prey if it strays closely enough. In pure ambush mode a mantis lashes out at remarkable speed when a target does get within reach, details of the speed and mode attack varying with the species. A mantis will catch prey items and grip them with grasping, spiked forelegs. The praying mantis usually holds its prey with one arm between the head and thorax, and the other on the abdomen. Then, if the prey does not resist, the mantis will eat it alive. However, if the prey does resist, the mantis will often eat it head first, some species of mantises being more prone to the behaviour than others. Unlike sucking predatory arthropods, a mantis does not liquefy prey tissues or drain its prey's body fluids, but simply slices and chews it with its mandibles as convenient, often from one end. If it should happen to have begun feeding on the midsection of the prey, it typically ends up eating first one remnant end from one foreclaw, then the rest from the other, leaving nothing but accidentally severed fragments such as limbs.Chinese Mantids have been found to gain benefits in survivorship, growth, and fecundity by supplementing their diet with pollen. In replicated laboratory tests the first instar actively fed on pollen just after hatching, thereby avoiding starvation in the absence of prey. The adults fed on pollen-laden insects, attaining fecundity as high as those fed on larger numbers of insects alone.

     Generally, mantises protect themselves by camouflage and concealment. When bothered enough, like when a human pinches their abdomens and moves his hand around them with sudden movements, many mantis species will stand tall and spread their forelegs, with their wings fanning out wide. The fanning of the wings makes the mantis seem larger and more threatening, with some species having bright colors and patterns on their hind wings and inner surfaces of their front legs for this purpose. If harassment persists, a mantis may strike with its forelegs and attempt to pinch or bite. As part of the threat display, some species also may produce a hissing sound by expelling air from the abdominal spiracles. When flying at night, at least some mantises are able to detect the echolocation sounds produced by bats, and when the frequency begins to increase rapidly, indicating an approaching bat, they will stop flying horizontally and begin a descending spiral toward the safety of the ground, often preceded by an aerial loop or spin.Mantises, like stick insects, show rocking behaviour in which the insect makes rhythmic, repetitive side-to-side movements. Functions proposed for this behaviour include the enhancement of crypsis by means of the resemblance to vegetation moving in the wind. However, the repetitive swaying movements may be most important in allowing the insects to discriminate objects from the background by their relative movement, a visual mechanism typical of animals with simpler sight systems. Rocking movements by these generally sedentary insects may replace flying or running as a source of relative motion of objects in the visual field. Mantises rock back and forth like the repetitive side-to-side movement when moving while a human is moving around near the mantis.



     Mantises are camouflaged, and most species make use of protective coloration to blend in with the foliage or substrate, both to avoidpredators, and to better snare their prey. Various species have evolved to not only blend with the foliage, but to mimic it, appearing as either living or withered leaves, sticks, tree bark, blades of grass, flowers, or even stones. Some species in Africa and Australia are able to turn black after a molt following a fire in the region to blend in with the fire ravaged landscape (a type of adaptive melanism referred to as fire melanism). While mantises can bite, they have no venom. They can also slash captors with their raptorial legs (which is often preceded by a threat display wherein the mantis will rear back and spread its front legs and wings (if present), often revealing vivid colors and/or eyespots to startle a predator). Mantises are without chemical protection; many large insectivores will eat a mantis, including Scops owlsshrikesbullfrogschameleons, and Milk Snakes.Sexual cannibalism is common among mantises in captivity, and under some circumstances may also be observed in the field. The female may begin feeding by biting off the male’s head (as they do with regular prey), and if mating has begun, the male’s movements may become even more vigorous in its delivery of sperm. Early researchers thought that because copulatory movement is controlled by a ganglion in the abdomen, not the head, removal of the male’s head was a reproductive strategy by females to enhance fertilisation while obtaining sustenance. Later, this behavior appeared to be an artifact of intrusive laboratory observation. Whether the behavior in the field is natural, or also the result of distractions caused by the human observer, remains controversial. Mantises are highly visual organisms, and notice any disturbance occurring in the laboratory or field such as bright lights or moving scientists. Research by Liske and Davis (1984) and others found (e.g. using video recorders in vacant rooms) that Chinese mantises that had been fed ad libitum (so that they were not hungry) actually displayed elaborate courtship behavior when left undisturbed. The male engages the female in courtship dance, to change her interest from feeding to mating. Courtship display has also been observed in other species, but it does not hold for all mantises.

     The reason for sexual cannibalism has been debated, with some considering submissive males to be achieving a selective advantage in their ability to produce offspring. This theory is supported by a quantifiable increase in the duration of copulation among males who are cannibalized, in some cases doubling both the duration and the chance of fertilization. This is further supported in a study where males were seen to approach hungry females with more caution, and were shown to remain mounted on hungry females for a longer time, indicating that males actively avoiding cannibalism may mate with multiple females. The act of dismounting is one of the most dangerous times for males during copulation, for it is at this time that females most frequently cannibalize their mates. This increase in mounting duration was thought to indicate that males would be more prone to wait for an opportune time to dismount from a hungry female rather than from a satiated female that would be less likely to cannibalize her mate. Some consider this to be an indication that male submissiveness does not inherently increase male reproductive success, rather that more fit males are likely to approach a female with caution and escape.The mating season in temperate climates typically begins in autumn. To mate following courtship, the male usually leaps onto the female’s back, and clasps her thorax and wing bases with his forelegs. He then arches his abdomen to deposit and store sperm in a special chamber near the tip of the female’s abdomen. The female then lays between 10 and 400 eggs, depending on the species. Eggs are typically deposited in a frothy mass that is produced by glands in the abdomen. This froth then hardens, creating a protective capsule. The protective capsule and the egg mass is called an ootheca. Depending on the species, the ootheca can be attached to a flat surface, wrapped around a plant or even deposited in the ground. Despite the versatility and durability of the eggs, they are often preyed on, especially by several species of parasitic wasps. In a few species, the mother guards the eggs.As in related insect groups, mantises go through three stages of metamorphosis: egg, nymph, and adult (mantises are among the hemimetabolic insects). The nymph and adult insect are structurally quite similar, except that the nymph is smaller and has no wings or functional genitalia. The nymphs are also sometimes colored differently from the adult, and the early stages are often mimics of ants. A mantis nymph increases in size (often changing its diet as it does so) by replacing its outer body covering with a sturdy, flexible exoskeletonand molting when needed. Molting can happen from five to ten times, depending on the species. After the final molt most species have wings, though some species are wingless or brachypterous ("short-winged"), particularly in the female sex.In tropical species, the natural lifespan of a mantis in the wild is about 10–12 months, but some species kept in captivity have been sustained for 14 months. In colder areas, females will die during the winter (as well as any surviving males).



     Organic gardeners who avoid pesticides may encourage mantises as a form of biological pest control. Tens of thousands of mantis egg cases are sold each year in some garden stores for this purpose.During fall, praying mantis females deposit an ootheca on the underside of a leaf or on a twig. If the egg case survives winter, the offspring, called nymphs, emerge in late spring or early summer. The nymphs have voracious appetites and typically cannibalize each other if they cannot find an adequate supply of aphids and other small insects. Egg cases are commercially available for placement in landscaping.However, mantises prey on neutral and beneficial insects as well, basically eating anything they can successfully capture and devour.Only one Spanish species, Apteromantis aptera, is listed as Lower Risk/Near Threatened. With one exception (the ground mantis Litaneutria minor in Canada, where it is rare — though it is common in the United States), North American mantises are not included among threatened or endangered species, though species in other parts of the world are under threat from habitat destruction. The European mantis (Mantis religiosa) is the state insect of Connecticut, but the General Statutes of Connecticut do not list any special protected status, as it is a non-native species from Europe and Africa.Over 20 species are native to the United States, including the common Carolina Mantis, with only one native to Canada. Two species (the Chinese Mantis and the European Mantis) were deliberately introduced to serve as pest control for agriculture, and have spread widely in both countries. Additionally, there is a strong market in the exotic pet trade for mantis species from Asia, Africa and South America, and many species are bred in captivity for this purpose.Southern African indigenous mythology refers to the praying mantis as a god in Khoi and San traditional myths and practices, and the word for the mantis in Afrikaans is hottentotsgot (literally, a god of the Khoi).Western descriptions of the biology and morphology of the mantises had become relatively accurate by the 18th century. Roesel von Rosenhofaccurately illustrated and described them in the Insekten-Belustigungen (Insect Entertainments). Aldous Huxley made philosophical observations about the nature of death while two mantises mated in the sight of two characters in the novel Island (the species was Gongylus gongylodes). The naturalist Gerald Durrell's autobiography My Family and Other Animals includes an account of a very evenly matched battle between a mantis and a gecko. Based upon empirical evidence, the Australian mantis has been known to strike fear amongst the native Australian gecko causing great avoidance tendencies as it marks its territory.M. C. Escher's woodcut Dream depicts a human-sized mantis standing on a sleeping bishop.Two martial arts that had been separately developed in China have movements and fighting strategies based on those of the Mantis. As one of these arts was developed in northern China, and the other in southern parts of the country, the arts are nowadays referred to (both in English and Chinese) as 'Northern Praying Mantis' and 'Southern Praying Mantis'. Both arts are very popular in China, and have also been imported to the West in recent decades.


     I was surprised by my friend Mr.Ajith Kamath's observation from the ground in Kudremukh, while trekking through one of the peaks in bright sunlight. This Mantis was a very tiny living being on the ground, which I couldn't notice untill it was shown to me and I did no delay but clicking this beauty from close-by. My Canon EF 300mm F4L IS USM lens + Tamron 1.4x extender on my Canon EOS 7D SLR, always helps me in getting good full frame macro images of butterflies, mantises, dragonflies, in most of my birding activities. I am thankful to my friends Mr. Ranganath Bhat, Mr.Kartik Bhat and Mr.Rajmohan M R for choosing this great heaven of earth for our weekend birding hobby, so that we came close to another beauty of nature " Praying Mantis", which taught me patience, perseverance and tolerance.
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