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Praying Mantises (Tamil: kumpidu poochie) Don’t be deceived by the pious name or the appearance of praying, because there’s nothing pious about the behaviour of these insects, whatsoever! In fact I sometimes think they would be more appropriately named Preying Mantises, as that’s what their praying posture is really all about. The Praying Mantis has awed and intrigued humans from earliest times with its distinctive mannerisms. It was the Greeks who first called it ‘Mantis’, meaning soothsayer, prophet, or diviner. Even today in many parts of the world it is treated with great awe and respect. Some consider it bad luck to kill or touch one. In parts of Italy they are thought to bewitch people. In Provence in France, a lost child is said to be able to find its way home from the direction in which a mantis points its leg. In Morocco, shepherds declare that if they get lost and find a mantis, it will point with its foreleg to the north. In Turkey and parts of West Asia they claim that it faces Mecca when it settles into its praying posture. In the Far East it has long been a symbol of bravery and ferocity; there’s even a Kung‑Fu posture which imitates it. And in ancient China their egg masses were prescribed as a cure for cramps, warts, gonorrhea, asthma, bladder troubles, hip pains and bed wetting. Some people even keep them as pets, as they accept handling. General introduction The closest insect relatives to mantises/mantids are the termites and cockroaches, from which they are thought to have descended. Or should one say ascended, as whilst termites are pests and cockroaches are reviled, mantids are on the whole respected or even revered. Altogether there are around 2,200 species worldwide, with maybe 200 in India, the vast majority located in tropical or sub‑tropical climates. They vary considerably in size, from ant-size species to some which are several inches long. Also colours and form vary according to habitat. Most range from leaf greens to earth or dust browns, but a few are highly coloured or superbly camouflaged, resembling flowers, twigs, grass, ants, dead leaves, or even bits of lichen or the bark of trees. Flight and escape Although they may have well developed wings – sometimes strikingly coloured – adult mantises are not strong fliers. The females of most species are in fact flightless. This, plus their often clumsy attempts at escape, leaves them somewhat vulnerable to fast moving determined predators, though like squirrels they are good at keeping on the opposite side of tree trunks or branches when the occasion warrants it. Mantises as predators It is as predators that mantises really come into their own. Firstly, they are equipped with excellent daytime eyesight, supported by an uncanny ability to swivel their head through 180 degrees. Once they spot 191 Praying Mantises a flying insect, their compound eyes lock on to it frontally, and the whole head swivels to follow its flight, rather like a gun turret on a ship. Their night vision, however, is poor, though they will often come to a light and take advantage of it to catch insects. Sometimes, slowly and stealthily, mantises will stalk their victims. Normally they just lie in wait, remaining – apart from occasional swaying like a wind‑blown leaf or blade of grass – rock still for long periods of time, with their two front legs raised in the classical “praying” posture. When they do move to take prey, it is with such speed and ferocity that the human eye can’t follow. In just a twentieth of a second their raised front legs lash out and back, impaling the victim on a row of vicious spikes on the inner edges of the legs. The action is comparable to the serrated blade of a clasp knife suddenly opening and then immediately snapping shut. Diet The prey of mantises generally includes any creatures small enough for them to successfully capture and devour, such as grasshoppers, crickets, caterpillars, butterflies, moths, spiders, flies, wasps, bees and other insects, all taken alive. In South America certain large mantises are also known to take small frogs, lizards, snakes, rodents and birds, such as humming birds (the only birds, incidentally, which can fly backwards!). Cannibalistic tendencies In addition to the above, in cannibalistic fashion all mantises devour other mantises. What’s more, that not only includes their brothers and sisters from the moment they are born, and any other mantises later encountered, including ones their own size, but also extends to the eating of mates. Like many female spiders, female mantises often kill their male suitors, eating them alive, even during the act of copulation. It is one of nature’s most grisly and fascinating sights. While the female may be steadily devouring the generally smaller male’s body from the head downwards over her shoulder, even with the head and thorax eaten the stump of the male’s abdomen on its remaining supporting legs may continue the mating action for hours, thanks to an independently operative nervous system (How’s that for sexual drive?) And as if that was not enough, the female will just as readily eat her own children when they hatch if she happens to be around! Finally, after eating, they go through a meticulous ritual clean‑up of their bloodied forelegs to remove all traces of the victim. At least, the books describe it as a clean-up, but perhaps all they are really doing is nibbling off the last tasty fragments, like someone sucking the remnants off an ice-cream stick? Photo: Igor Siwanowicz Courtship behaviour Although sexual cannibalism is common in captivity, and under some circumstances may also be seen in the wild, Mantises are highly visual creatures, aware of everything that is happening around them, and it’s not clear whether or not having human observers watching them affects their behaviour. Research using video recorders in vacant rooms, for example, found that mantises that were not hungry or being watched actually displayed elaborate courtship behaviour, the male engaging the female in a courtship dance to shift her focus from her normal pattern of feeding to mating. Successful males usually leap onto the female’s back, clasp her thorax and wing bases with their forelegs, then arch their abdomen to deposit and store sperm in a special chamber near the tip of her abdomen. So far so good, but it is the act of dismounting that is one of the most dangerous times for males, because it is at this time that females most frequently cannibalize their mates. Perhaps in awareness of this, many males remain in the mounted position for an extended period of time, presumably waiting for an opportune moment to safely dismount and get away from a possibly hungry female. Successful males who succeed and have avoided being eaten get to mate with other females. 192 Praying Mantises Egg laying A well nourished female mantis of certain species may lay up to ten times a year, commencing in each case two days after mating. They usually lay in a head‑down‑tail‑up posture, leaving a typically-shaped ootheca (egg case, see right) similar to those of cockroaches, covered in a frothy substance that quickly hardens to insulate and protect the eggs. In this manner anything from ten to several hundred eggs may be laid after each mating, attached to tree trunks, plant stems, rocks or walls, or placed in soil or grass. The females of some species remain with the eggs till they hatch; others abandon them, whereupon the eggs become vulnerable to attack from several species of parasitic wasps. Metamorphosis As in related insect groups, mantises go through three stages of metamorphosis, namely egg, nymph and adult, with the nymph and adult insect physically quite similar. (The nymph is just smaller and has no wings or functional genitalia, is often coloured differently to the adult, and in the early stages may mimic ants.) On hatching, baby mantises quickly scatter to avoid each other’s cannibalistic tendencies. They then take up an independent existence, growing to maturity through 6‑9 moults. Not all make it, of course. Apart from the risk of being eaten by fellow mantises, they also fall victim as newly emerged infants to ants, then later to certain reptiles, birds and various small-to-medium size mammals. Defence Generally speaking, mantises are protected against predation simply by virtue of concealment, in that most species make use of protective body colouring to blend in with the background. However, various species have gone even further, and 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 also able to turn black after a moult following a bush fire in the region, to blend in with the fire-ravaged landscape. When concealment fails and they are directly threatened, the mature insects of many species can put up a good defence. They stand tall and spread their spiked forelegs, with their wings fanning out wide to make them seem larger and more threatening, with some species having bright colours and patterns on their hindwings and inner surfaces of their front legs for this purpose. They can also bite or even strike at their attackers with their spiked forelegs, and in the case of small birds sometimes damage the eyes. As part of the threat display, some species may also produce a hissing sound by expelling air from their abdominal spiracles. When flying at night, at least some of the mantis species are able to detect the echo-location sounds produced by bats, and when the Photo: Igor Siwanowicz 193 Praying Mantises frequency begins to increase rapidly – indicating an approaching bat – will stop flying horizontally and begin a descending spiral toward the safety of the ground, often preceded by an aerial loop or spin. The only defence mechanism they apparently lack is chemical defence. Mantises and humans From the human point of view mantises play an important role in reducing pest insects. Many farmers deliberately introduce them by depositing their egg cases among vulnerable crops. The only problem is that they also kill beneficial insects which might be supportive of agriculture through pollination. On balance, however, as non‑vegetarians they are very much welcomed. Sparse distribution, for good reason Not surprisingly, bearing in mind their ferocity and their readiness to see each other as potential snacks, they are quite sparsely distributed. It’s even said that you’ll rarely find more than one to a bush. That is, until mating time, when the males – attracted by a no doubt irresistibly delicious pheromone – go a’courting. Do they know the risks they take? Perhaps, because they certainly don’t rush in like mad fools. They have been known to take up to an hour to close the last 30cms/12in. to the female! What happens next must largely be a matter of luck, and perhaps the state of the lady’s appetite. Many males escape unscathed. But many don’t. Thankfully human love affairs are different, and the worst that most men can expect (unless married to someone like Lorena Bobbit) is to be verbally “chewed-up” by an irate partner as opposed to literally being eaten alive in course of the mating act. If they weren’t, perhaps more men would opt to become brahmacharis?! Additional miscellania * Regarding their conservation status, only one species (Spanish) is listed as Lower Risk/Near Threatened, though various species in some parts of the world are under increasing threat from habitat destruction. * Organic gardeners who avoid pesticides welcome mantises as a form of biological pest control. Tens of thousands of their egg cases are sold each year in certain garden stores in the West for this purpose. * In tropical species, the natural lifespan of a mantis in the wild is about 10-12 months, but some species kept in captivity have lived for 14 months. 194