Charles Dixon
Published: 2013-09
Total Pages: 52
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1898 edition. Excerpt: ... ages, all living things have been (and still continue to be) unceasingly striving, under the influence of certain well-recognised laws, to adapt themselves to more or less constantly changing conditions of existence. What is popularly known as the "balance of nature" is the primal result of these incessant efforts of organisms, one acting upon the other in countless ways, to maintain a place in the ranks of struggling life. We can very forcibly illustrate these remarks by quoting one or two classical instances recorded by Darwin. Certainly one of the most complex of these is that which illustrates the intricate connection between, and interdependence upon, such widely different organisms as a carnivorous animal and a scented yet lowly flower. Perhaps every reader may be aware that certain flowers absolutely depend upon the visits of insects to fertilise them. They cannot produce seed without such visits; and in a great many instances this fertilisation can only be accomplished by a certain species of insect. Now, one of our commonest flowers, the red clover, is largely, perhaps we might almost say entirely, fertilised by our little friend the humble-bee. If these bees do not visit the clover flowers, those flowers are sterile and produce no seeds. But the humble-bees have a deadly enemy in the field-mice, which destroy, it has been computed, no less than twothirds of their nests and combs. The mice in their turn are destroyed by cats, Owls, Kestrels; so that in localities where the enemies of mice are common the bees have more chance of multiplying, and the flowers a correspondingly greater facility for fertilisation. The abundance of clover in a district may therefore depend upon the number of cats, of Owls and Kestrels! Take another...