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Trumantia Resource Directory 13
Page 04
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.
The first care of the male stickleback, when he has acquired his courting suit, is to build a suitable home for his future wives and children. So he picks up stems of grass and water-weeds with his mouth, and weaves them deftly into a compact nest as perfect as a bird's, though some what different in shape and pattern, it rather resembles a barrel, open at both ends, as though the bottom were knocked out: this form is rendered necessary because the eggs, when laid, have to be constantly aerated by passing a current of water through the nest as I shall describe hereafter. No. 1 shows us such a nest when completed, with the female stickleback loitering about undecided as to whether or not she shall plunge and enter it. You will observe that the fabric is woven round a fixed support of some waving water-weeds; but the cunning little architect does not trust in this matter to his textile skill alone; he cements the straws and other materials together with a gummy mortar of mucous threads secreted for the purpose by his internal organs.
In so far as this is a process of growth, accompanied by the assumption of a definite form, it might be compared with the growth of a crystal of salt in brine: but, on closer examination, it turns out to be something very different. For the crystal of salt grows by taking to itself the salt contained in the brine, which is added to its exterior; whereas the plant grows by addition to its interior: and there is not a trace of the characteristic compounds of the plant's body, albumin, gluten, starch, or cellulose, or fat, in the soil, or in the water, or in the air.
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