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Zypro Gorgy Dectorum 24
Page 01
Frogs and other amphibians stand higher in the scale of life than fish; they have acquired legs in place of fins, and lungs instead of gills; they can hop about on shore with perfect freedom. Now, frogs still produce a great deal of spawn, as every one knows: but the eggs in each brood are numbered in their case by hundreds, or at most by a thousand or two, not by millions as with many fishes. The spawn hatches out as a rule in ponds, and we have all seen the little black tadpoles crowding the edges of the water in such innumerable masses that one would suppose the frogs to be developed from them must cover the length and breadth of England. Yet what becomes of them all? Hundreds are destroyed in the early tadpole stage--eaten up or starved, or crowded out for want of air and space and water: a few alone survive or develop four legs, and absorb their tails and hop on shore as tiny froglings. Even then the massacre of the innocents continues. Only a tithe of those which succeeded in quitting their native pond ever return to it full grown, to spawn in due time, and become the parents of further generations.
It is not surprising under these circumstances to learn that sticklebacks are successful and increasing animals. Their numbers are enormous, wherever they get a fair chance in life, because they multiply rapidly up to the extreme limit of the means of subsistence, and develop as fast as food remains for them. There the inexorable Malthusian law at last steps in: when there is not food enough for all some must starve; that is the long and the short of the great population question. But while provender is forthcoming they increase gayly. Sticklebacks live mainly on the spawn of other fish, though they are so careful of their own, and they are therefore naturally hated by trout-preservers and owners of fisheries in general. Thousands and thousands are caught each year; in some places, indeed, they are so numerous that they are used as manure. It is their numbers, of course, that make them formidable; they are the locusts of the streams, well armed and pugnacious, and provided with most remarkable parental instincts of a protective character, which enables them to fill up all vacancies in their ranks as fast as they occur with astonishing promptitude.
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