WHY SOME TAILS WERE CREATED.

King Country Chronicle, Volume VI, Issue 476, 22 June 1912, Page 7

WHY SOME TAILS WERE CREATED.

>T"« 1 " j " QUEER THINGS THEY DO. We are very apt to regard the tail is merely '"the other end of the )ody," but as Mr. James N. Beckett aas pointed out in an amusing paper, Nature seems to have early esteemed thq member and made it her most »fficient implement of locomotion, as in the case of fish. Among the insects closely related the tail is interesting as a support for various implements, useful in their economy,- such as stings, ovipositors and pincers. The first two are common, and the last may he seen on the end of the male dragon fly, whereby he clasps the slender neck of his mate and steadies her while she, with much effort, thrusts her ovipositor into a tough reed stem. This is a case where there are two remarkable terminal implements in the family. The tail reaches its perfection as an essential in the fishes, where, as noted, it is almost solely the means of motion, for. the fins are largely balancing members. The terminal fringe is, without doubt, the parent of the upper and lower unpaired fins, and it is not improbable that the paired fins came out of it also. If this be true, the legs of the quadruped had their origin here and the human hand may have been cradled with the caudal fin among the rushes. The shape and other characteristics of the tail-fin may tell much of a fish's ancestry and modern habits, 3ut further discussion of this is pre-

eluded here, more than to say that those swimmers with tails widely forked are apt to be more speedy and game than those with square or rounded tails. The higher fishes have the tail stuck straight into the fringe but those of the shark tribe have it turned* up within the fin, like n sledge runner ; and usually their upper lobe or fork is the longer. This is so exagerated in one shark called the thresher that while lying on the surface it can thresh or strike the whale well up on his great sides ; and an attack of a few of such larnbasters is said to prove fatal to the leriathan at times.

rilE SEA HORSE'S PREHENSILE APPENDAGE.

Among the peculiar tailed fishes the sea horses are alone in having the tail prehensile. With it they inchor themselves to seaweed and other things in strong currents, for they arc poor swimmers. Here, too, is the first manifestation of the amotions by means of the vertebrate tail, for as two of these interesting creatures meet they may clasp tails for a moment and then pass on, as if they had wished each other well. They have thus antedated our handshake a few cycles.

Among thei reptiles only is the tail used as a prepaid ransom, or a sacriicial offering. Many of the lizards lave the organ so feebly connected lip as to break off easily, if it be. pulled at as the creature tries to sscape, and the owner is thus able :o go maimed into; safety rather than •emain whole in the stomach of the memy. Thus, the little so-called grass snake has such a tail in great Dcrfection. Between the joints of the

rertebrae run gristly septums or iiscs. They adhere so slightly- to the tissues which they touch that the

'xertions of the lizard itself, in a sudden attempt to escape,'may break the tail, and a slight blow with a switch at the joints causes fracture.

The wriggling remnant is such an ittractive tidbit to the pursuer that he may allow the body to go. Inieed, the owner itself has been mown to turn and swallow its own extremity, perhaps without knowing ,vhat it is. For these reasons this lizard is in some regions called the 'jointed snake." The parts never •e-assemble, as is popularly claimed, but the creature can grow a new tail. It is not, however,, so wellshaped as the old one.

In this connection it may be said that the ready manner in which the skin slips on the tails of many relents seems to imply some similar purpose, and the tail feathers of birds arc always loosely set for the

same reason. The squirrel very consciously puts his tail between his body and an expected danger, explores doubtful places with it stuck out well in front of him, and curls it over his back when he eats, as much as a shield as an ornament. In all these cases his hope ia that :f the enemy make a dash the tail may be grasped and the body missed his worst foe being usually the hawk above him. THE MONSTER'S FIFTH LEG. Besides its aid in flying, the reptiles first used the tail as a balancing member, and as a fifth leg when sitting up bipedally. The old fossil monsters so braced themselves while resting, and such as walked like birds, and made those celebrated bird-like tracks may have used it as a balancing pole, as they strode. Of course, many quadrupeds higher up the scale sit erect by the use of the tail as a prop, notably tho kangaroo.

The snakes have the honour 0 f first making the tail a musical instrument, for more than one of these horny tips may vibrate in anger against dead leaves, or grass, to make a whirring sound of bluff 01 threat. It has been thought by some students that this is done in conscious imitation of the peculiar sound of the rattlesnake, but it is more likely that the latter's melody is only a greater development of musical . talent .on a much superior

instrument. By som3 lucky means he was not able to complete his

moult, and portions of his old skin remained after each shedding till he found a toy which became useful as a means of safety, and persisted because of such purpose. Some of the most formidable creatures ever known, especially for defence, were the old fossil reptiles, on the terribly muscled tails of which, scores of feet long, were fearful three-pointed spines. The alligator faintly keeps up the reputation of the family in this respect, and the monitor lizards strike a stinging lash with their whip-like tails. The bird's tail is not so useful in flight as is usually supposed, and while one suddenly deprived of it may fly awkwardly at first lvn sodii adjusts himself to the new condition It is only slightly used as a si.lcwise rudder, notwithstanding the frequent assertion of even fairly gcol observers, and is not essential tc guiding or rapid turning. Some o! the birds and flyers that take insects most expertly in the air have short tails, such as bats and swifts and hawks, and those with long tails are by no means among the great pursuers.

In alighting, in stopping suddenly, in any up-and-down motion and in balancing while sailing, the bird's tail has its greatest use, and it began its career evidently ; as a kitelike surface in rising and sailing down, while the legs of the first, bird known were made Tjroad by similai horizontal feathers for the same evident purpose. In a few birds,, now, such as' woodpeckers, swifts, etc., the tail is used as a prop.— "Popular Science Sittings."