THE INSECT WORLD

Evening Post, Volume CIX, Issue 37, 13 February 1930, Page 28

THE INSECT WORLD

ART OF CAMOUFLAGE WALKING TWIGS AND LEAVES PUZZLE FOE SCIENTISTS ; (Copyright.) By means of intricate de-ices, costly chemicals, and much ingenuity man has been able to make paper flowers, synthetic fruit, and machines that fly like the birds, even if they1 do not resemble them. Man has great imitative ability provided only that he can use the chemical vegetable and mineral worlds, tor sources of supply. Individually he cannot change his appearance enough to fool even the dullest enemy haunting his trail, not even to save his life. Nature has treated her insects better ill the matter of providing them with more imitative ability than has been given man. So complete, in some ,instances, has been this knowledge aa to how to look like something else, that it was not until very recently that scientists have been able to even find them, for many "Ihave not been classified, or even placed: in museums. A whole world of strange insects exist in the tropical countries almost unknown to the 'expert entomologists, chiefly because these same insects have an almost uncanny ability to imitate the plants, the trees, the leaves and the inanimate things about them. Arthur H. Fisher, an American naturalist, recently returned from long months in the jungles of New Guinea and the Amazon Basin of Brazil, captured, after long patient watching, a few samples of these imitative creatures hitherto unknown to modern man. LEAVES THAT WALK. Pushing, his'way through the tangled growth of the tropical forest he was surrounded by countless strange and •wonderful creatures, some of them minute, but many true leviathans of the insect world. Watching closely he would occasionally see a large twig separato from its neighbours and walk away in the most mysterious manner. Then again, he. would see a green leaf suddenly become an animated thing and fly away and attach itself. to. a nearby group. Under such circumstances if he moved quickly, he could capture a rare "walking-stick" and the leaf might prove to be another species of the same group, or perhaps a katydid with a feamouflage complex developed beyond belief. The restless native or the untrained observer moving through the tropical growth would easily pass by grasshoppers and patydids as large as finches, or other birds, or walking-sticks a foot in length, and all within the grasp of his hand, yet be absolutely unaware of their existence, so perfect is the insects' ability to simulate the leaf ortwig. . ■■■ • .■/■■;• Such miracles are only possible in the tropical jungles and could never happen in our own temperate zones. The warm regions around the centre circumference of the earth are ideal for growth of insects. There is no winter, no spring and no autumn. There is only perpetual summer. Every day is like every.other day and jjvery to-morrow •will be like yesterday. Under such, conditions, harmless and dangerous'insects develop along gigantic lines. The fighting bugs are generally not so numerous' as they are aggressive, according to this, naturalist. They have a high degree of efficiency and are ono hundred per cent, prepared to battle, and thus wage constant warfare on men. But in the tropical forests there are hundreds of insects that are shy and retiring and do not intrude, themselves upon man. They hide by imitating the growths all about them, and for this reason they are rarely found. KATYDIDS LIKE LEAVES. Mr. Fisher, says that he has seen a huge butterfly, whose upper wing surfaces reflect the fleeting lights in gorgeous Colours, suddenly alight with folded wings against a background of neutral browns, to appear instantly as a dead or dying leaf, or even perhaps strikingly to mimic Borne forest creature feared by enemies of the butterfly. ■This remarkable sense of simulation and mimicry, 'and ability to camouflageand fade into the distinct backgrounds of their chosen environment, is their best protection both from devouring by their enemies and even from capture by men. A katydid may pause amid the brilliant green leaves of the bush it is equipped by "Nature to imitate, there to remain motionless, its antennae extended to the branch, to stimulate further the tendrils of the true leaf it seeks to portray. Colour texture and even the delicate and intricate veins of the adjoining leaves are reproduced. Possibly the most unusually successful of the imitative insects is the leaflike walking-stick from Ceylon, aptly named Phyllium pulchrifolium, which is the last word in leaf camouflage, where even the legs are elaborately curtained with pale green p«eudo-foliage. The grandfather of all the walkingstick family comes from the Amazon Basin of Brazil—the giant Gladomorphus—which attains twelve inches in length. Yet so perfectly does this weird insect resemble and mimic the stems of the plants on whose foliage it feeds that but few collectors have ever brought back an adult specimen. Another giant of this grotesque tribe is the spiny horrida variety from New Guinea. This ugly but wholly harmless insect wisely uses its spiny protective garb in accordance with the first law of Nature, selecting its home in the forest among spiny and formid' able surroundings. The fields of Nature are filled with curious bugs of prey. All the fierce animals well known to man have their similar type 3in bugdoin except that many of the latter are much more cunning. . "'■■■■ LOOKS LIKE A FLOWER BUD. Where in the animal kingdom will one find anything like the praying vi mtis, which receives its name from tlio habit of sitting erect on a twig, motionless for hours, with its front legs clasped together as if in an attitude of prayer? Thus it awaits its prey. Because of its ability to sit like a part of a branch or dried leaf it catches its prey and devours ants, caterpillars, or other insects that come within reach. Another, known as the reahorse, is too a large insect, very uncommon and rarely seen, because it is very much like the foliage in colour. In, Java and elsewhere in the Malay Archipelago there is a related species of which little is known. It is a great imitator And deceiver, but it is called the diabolical spectre. It is one ofi the most beautiful of insects and perched in the middle of a flower cluster of which it appears to be the most beautiful part, it waits for a butterfly or other prey, to alight. In the' Belgian Congo there is a great grasshopper of giant size, and from meagre repqrtaat is'claimed that it will catch mice and other small creatures.. Very little is really known of the life history of the giant elephant rhinoceros beetles of South America except that they do not bite at once! This naturalist cannot tell you why these huge boetles evolved such imposing horns. He may suggest that they use them, to cut off foliage for food. These are !but a few of the mysteries of insect life. The large group which embraces the grasshoppers, the

katydids, crickets, ■mantises, cockroaches, ' and the earwigs, those strange little insects that carry a pair of forceps as a casual adornment, are but xety little understood. In the junj^tfs this group grows to enormous proportions and they show unusual traits and live according to their own lawa that appear entirely different from the supposed laws of their tiny relations in the temperate zones.